0.6 A, DC-to-DC Switching Regulator with Independent

1 A/0.6 A, DC-to-DC Switching Regulator with Independent Positive and Negative Outputs Data Sheet ADP5070 Rev. B Document Feedback Information furnish...

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1 A/0.6 A, DC-to-DC Switching Regulator with Independent Positive and Negative Outputs

ADP5070

Data Sheet FEATURES

TYPICAL APPLICATION CIRCUIT ADP5070 SS

INBK

RC1

L1

COMP1

VPOS

CC1

SW1

EN1

D1 RFT1

CVREG FB1

VREG

RFB1 VIN CIN1

PVIN1 PVIN2 PVINSYS

PGND

EN2

VREF

COUT1

CVREF RFB2

RC2

FB2

COMP2 CC2 SYNC/FREQ SLEW SEQ AGND

COUT2

RFT2

SW2 D2 L2

VNEG 12068-001

Wide input supply voltage range: 2.85 V to 15 V Generates well regulated, independently resistor programmable VPOS and VNEG outputs Boost regulator to generate VPOS output Adjustable positive output to 39 V Integrated 1.0 A main switch Optional single-ended primary-inductor converter (SEPIC) configuration for automatic step-up/step-down Inverting regulator to generate VNEG output Adjustable negative output to VIN − 39 V Integrated 0.6 A main switch True shutdown for both positive and negative outputs 1.2 MHz/2.4 MHz switching frequency with optional external frequency synchronization from 1.0 MHz to 2.6 MHz Resistor programmable soft start timer Slew rate control for lower system noise Individual precision enable and flexible start-up sequence control for symmetric start, VPOS first, or VNEG first Out-of-phase operation UVLO, OCP, OVP, and TSD protection 4 mm × 4 mm, 20-lead LFCSP and 20-lead TSSOP −40°C to +125°C junction temperature range Supported by the ADIsimPower tool set

Figure 1.

APPLICATIONS Bipolar amplifiers, ADCs, DACs and multiplexers Charge-coupled device (CCD) bias supply Optical module supply RF power amplifier (PA) bias

GENERAL DESCRIPTION The ADP5070 is a dual high performance dc-to-dc regulator that generates independently regulated positive and negative rails. The input voltage range of 2.85 V to 15 V supports a wide variety of applications. The integrated main switch in both regulators enables generation of an adjustable positive output voltage up to +39 V and a negative output voltage down to −39 V below input voltage. The ADP5070 operates at a pin selected 1.2 MHz/2.4 MHz switching frequency. The ADP5070 can synchronize with an external oscillator from 1.0 MHz to 2.6 MHz to ease noise filtering in sensitive applications. Both regulators implement programmable slew rate control circuitry for the MOSFET driver stage to reduce electromagnetic interference (EMI). Flexible start-up sequencing is provided with the options of manual enable, simultaneous mode, positive supply first, and negative supply first. Rev. B

The ADP5070 includes a fixed internal or resistor programmable soft start timer to prevent inrush current at power-up. During shutdown, both regulators completely disconnect the loads from the input supply to provide a true shutdown. Other key safety features in the ADP5070 include overcurrent protection (OCP), overvoltage protection (OVP), thermal shutdown (TSD), and input undervoltage lockout (UVLO). The ADP5070 is available in a 20-lead LFCSP or in a 20-lead TSSOP and is rated for a −40°C to +125°C junction temperature range. Table 1. Family Models Model ADP5070 ADP5071

Boost Switch (A) 1.0 2.0

Inverter Switch (A) 0.6 1.2

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ADP5070* PRODUCT PAGE QUICK LINKS Last Content Update: 11/29/2017

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REFERENCE MATERIALS

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EVALUATION KITS

• Bias Generation and Level Setting Made Easy with Multiple Range, User Programmable Voltage Output D/A Converter

• ADP5070/ADP5071 Evaluation Board

DOCUMENTATION Application Notes • AN-1359: Low Noise, Dual-Supply Solution Using the ADP5070 for the Precision AD5761R Bipolar DAC in Single-Supply Systems

DESIGN RESOURCES • ADP5070 Material Declaration • PCN-PDN Information • Quality And Reliability • Symbols and Footprints

• AN-1366: Using the ADP5070/ADP5071 to Create Positive and Negative Voltage Rails when VOUT < VIN

DISCUSSIONS

• AN-1368: Ferrite Bead Demystified

View all ADP5070 EngineerZone Discussions.

Data Sheet • ADP5070: 1 A/0.6 A, DC-to-DC Switching Regulator with Independent Positive and Negative Outputs

SAMPLE AND BUY Visit the product page to see pricing options.

User Guides • UG-758: Evaluating the ADP5070CP/ADP5071CP LFCSP DC-to-DC Switching Regulators/Converters • UG-848: Evaluating the ADP5070RE/ADP5071RE TSSOP DC-to-DC Switching Regulators/Converters

TOOLS AND SIMULATIONS • ADIsimPower™ Voltage Regulator Design Tool

TECHNICAL SUPPORT Submit a technical question or find your regional support number.

DOCUMENT FEEDBACK Submit feedback for this data sheet.

• ADP507x Design Tool

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ADP5070

Data Sheet

TABLE OF CONTENTS Features .............................................................................................. 1

Soft Start ...................................................................................... 15

Applications ....................................................................................... 1

Slew Rate Control ....................................................................... 15

Typical Application Circuit ............................................................. 1

Current-Limit Protection ............................................................ 15

General Description ......................................................................... 1

Overvoltage Protection .............................................................. 15

Revision History ............................................................................... 2

Thermal Shutdown .................................................................... 15

Specifications..................................................................................... 3

Start-Up Sequence ...................................................................... 15

Absolute Maximum Ratings ............................................................ 5

Applications Information .............................................................. 17

Thermal Resistance ...................................................................... 5

ADIsimPower Design Tool ....................................................... 17

ESD Caution .................................................................................. 5

Component Selection ................................................................ 17

Pin Configurations and Function Descriptions ........................... 6

Loop Compensation .................................................................. 20

Typical Performance Characteristics ............................................. 8

Common Applications .............................................................. 22

Theory of Operation ...................................................................... 14

Super Low Noise With Optional LDOs................................... 24

PWM Mode ................................................................................. 14

SEPIC Step-Up/Step-Down Operation ................................... 25

PSM Mode ................................................................................... 14

Layout Considerations ............................................................... 26

Undervoltage Lockout (UVLO) ............................................... 14

Outline Dimensions ....................................................................... 27

Oscillator and Synchronization ................................................ 14

Ordering Guide .......................................................................... 27

Internal Regulators ..................................................................... 14 Precision Enabling ...................................................................... 15

REVISION HISTORY 7/2017—Rev. A to Rev. B Changes to Table 10 and Table 11 ................................................ 23 Updated Outline Dimensions ....................................................... 27 Changes to Ordering Guide .......................................................... 27 6/2015—Rev. 0 to Rev. A Added 20-Lead TSSOP ...................................................... Universal Changes to Table 3 and Table 4 ....................................................... 5 Added Figure 3, Renumbered Sequentially .................................. 6 Changes to Figure 29 Caption and Figure 32 Caption .............. 11 Changes to Figure 37 Caption to Figure 39 Caption ................. 13 Changes to Internal Regulators Section ...................................... 14 Change to Soft Start Section.......................................................... 15 Changes to Output Capacitors Section, Soft Start Resistor Section, and Diodes Section ......................................................................... 18 Changes to Figure 50 Caption....................................................... 26 Added Figure 51.............................................................................. 26 Updated Outline Dimensions ....................................................... 27 Changes to Ordering Guide .......................................................... 27 2/2015—Revision 0: Initial Version

Rev. B | Page 2 of 27

Data Sheet

ADP5070

SPECIFICATIONS PVIN1 = PVIN2 = PVINSYS = 2.85 V to 15 V, VPOS = 15 V, VNEG = −15 V, fSW = 1200 kHz, TJ = −40°C to +125°C for minimum/maximum specifications, and TA = 25°C for typical specifications, unless otherwise noted. Table 2. Parameter INPUT SUPPLY VOLTAGE RANGE QUIESCENT CURRENT Operating Quiescent Current PVIN1, PVIN2, PVINSYS (Total) Shutdown Current UVLO System UVLO Threshold Rising Falling Hysteresis OSCILLATOR CIRCUIT Switching Frequency SYNC/FREQ Input Input Clock Range Input Clock Minimum On Pulse Width Input Clock Minimum Off Pulse Width Input Clock High Logic Input Clock Low Logic PRECISION ENABLING (EN1, EN2) High Level Threshold Low Level Threshold Shutdown Mode Pull-Down Resistance INTERNAL REGULATOR VREG Output Voltage BOOST REGULATOR Feedback Voltage Feedback Voltage Accuracy Feedback Bias Current Overvoltage Protection Threshold Load Regulation Line Regulation Error Amplifier (EA) Transconductance Power FET On Resistance Power FET Maximum Drain Source Voltage Input Disconnect Switch On Resistance Current-Limit Threshold Minimum On Time Minimum Off Time

Symbol VIN

Min 2.85

Typ

Max 15

Unit V

Test Conditions/Comments PVIN1, PVIN2, PVINSYS

IQ

3.5

4.0

mA

ISHDN

5

10

µA

No switching, EN1 = EN2 = high, PVIN1 = PVIN2 = PVINSYS = 5 V No switching, EN1 = EN2 = low, PVIN1 = PVIN2 = PVINSYS = 5 V

VUVLO_RISING VUVLO_FALLING VHYS_1

2.85

2.5

2.8 2.55 0.25

V V V

fSW

1.130 2.240

1.200 2.400

1.270 2.560

MHz MHz

fSYNC tSYNC_MIN_ON tSYNC_MIN_OFF VH (SYNC) VL (SYNC)

1.000 100 100

2.600

MHz ns ns V V

VTH_H VTH_L VTH_S

1.125 1.025 0.4

PVINSYS

1.3 0.4 1.15 1.05

1.175 1.075

V V V

REN

1.48



VREG

4.25

V

VFB1

0.8 −0.5 −1.5

IFB1 VOV1 ∆VFB1/ILOAD1 ∆VFB1/VPVIN1 gM1 RDS (ON) BOOST VDS (MAX) BOOST RDS (ON) INBK ILIM (BOOST)

270

1.00

+0.5 +1.5 0.1 0.86 0.0003 0.002 300 175 39 210 1.10 50 25

Rev. B | Page 3 of 27

330

1.20

V % % µA V %/mA %/V µA/V mΩ V mΩ A ns ns

SYNC/FREQ = low SYNC/FREQ = high (connect to VREG)

Internal circuitry disabled to achieve ISHDN

TJ = 25°C TJ = −40°C to +125°C At FB1 pin ILOAD11 = 5 mA to 150 mA VPVIN1 = 2.85 V to 14.5 V, ILOAD11 = 15 mA

ADP5070 Parameter INVERTING REGULATOR Reference Voltage Reference Voltage Accuracy

Symbol

Feedback Bias Current Overvoltage Protection Threshold Load Regulation

IFB2 VOV2 ∆(VREF − VFB2)/ ILOAD2 ∆(VREF − VFB2)/ VPVIN2 gM2 RDS (ON) INVERTER VDS (MAX) INVERTER

Hiccup Time THERMAL SHUTDOWN Threshold Hysteresis

Typ

Unit

0.74 0.0004

V % % V % % µA V %/mA

0.003

%/V

+0.5 +1.5 0.8

−0.5 −1.5

ILIM (INVERTER)

Max

1.60 −0.5 −1.5

VREF − VFB2

EA Transconductance Power FET On Resistance Power FET Maximum Drain Source Voltage Current-Limit Threshold Minimum On Time Minimum Off Time SOFT START Soft Start Timer for Boost and Inverting Regulators

Min

VREF

Feedback Voltage Feedback Voltage Accuracy

Line Regulation

1

Data Sheet

+0.5 +1.5 0.1

270

300 350 39

330

µA/V mΩ V

600

660 60 50

720

mA ns ns

Test Conditions/Comments

TJ = 25°C TJ = −40°C to +125°C TJ = 25°C TJ = −40°C to +125°C At FB2 pin after soft start has completed ILOAD21 = 5 mA to 75 mA VPVIN2 = 2.85 V to 14.5 V, ILOAD21 = 15 mA

tSS

4

ms

SS = open

32 8 × tSS

ms ms

SS resistor = 50 kΩ to GND

tHICCUP TSHDN THYS

150 15

°C °C

ILOADx is the current through a resistive load connected across the output capacitor (where x is 1 for the boost regulator load and 2 for the inverting regulator load).

Rev. B | Page 4 of 27

Data Sheet

ADP5070

ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE

Table 3. Parameter PVIN1, PVIN2, PVINSYS INBK SW1 SW2 PGND, AGND VREG EN1, EN2, FB1, FB2, SYNC/FREQ COMP1, COMP2, SLEW, SS, SEQ, VREF Operating Junction Temperature Range Storage Temperature Range Soldering Conditions

Rating −0.3 V to +18 V −0.3 V to PVIN1 + 0.3 V −0.3 V to +40 V PVIN2 − 40 V to PVIN2 + 0.3 V −0.3 V to +0.3 V −0.3 V to lower of PVINSYS + 0.3 V or +6 V −0.3 V to +6 V −0.3 V to VREG + 0.3 V

θJA and ΨJT are based on a 4-layer printed circuit board (PCB) (two signal and two power planes) with nine thermal vias connecting the exposed pad to the ground plane as recommended in the Layout Considerations section. θJC is measured at the top of the package and is independent of the PCB. The ΨJT value is more appropriate for calculating junction to case temperature in the application. Table 4. Thermal Resistance

−40°C to +125°C

Package Type 20-Lead LFCSP 20-Lead TSSOP

−65°C to +150°C JEDEC J-STD-020

ESD CAUTION

Stresses at or above those listed under Absolute Maximum Ratings may cause permanent damage to the product. This is a stress rating only; functional operation of the product at these or any other conditions above those indicated in the operational section of this specification is not implied. Operation beyond the maximum operating conditions for extended periods may affect product reliability.

Rev. B | Page 5 of 27

θJA 60.2 58.5

θJC 36.5 35.0

ΨJT 0.63 0.60

Unit °C/W °C/W

ADP5070

Data Sheet

ADP5070 TOP VIEW (Not to Scale)

15 14 13 12 11

PVIN1 VREG AGND VREF FB2

NOTES 1. EXPOSED PAD. CONNECT THE EXPOSED PAD TO AGND.

1

20 SW2

SW1

2

19 PVIN2 18 PVINSYS

INBK

3

SYNC/FREQ

4

SEQ

5

SLEW

6

15 AGND

FB1

7

14 VREF

COMP1

8

13 FB2

EN1

9

12 COMP2

SS 10

12068-002

1 2 3 4 5

COMP1 6 EN1 7 SS 8 EN2 9 COMP2 10

INBK SYNC/FREQ SEQ SLEW FB1

PGND

17 PVIN1

ADP5070 TOP VIEW

16 VREG

11 EN2

12068-050

20 19 18 17 16

SW1 PGND SW2 PVIN2 PVINSYS

PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS

NOTES 1. EXPOSED PAD. CONNECT THE EXPOSED PAD TO AGND.

Figure 2. 20-Lead LFCSP Pin Configuration

Figure 3. 20-Lead TSSOP Pin Configuration

Table 5. Pin Function Descriptions Pin No. LFCSP TSSOP 1 3 2 4

Mnemonic INBK SYNC/FREQ

3

5

SEQ

4

6

SLEW

5

7

FB1

6

8

COMP1

7

9

EN1

8

10

SS

9

11

EN2

10

12

COMP2

11

13

FB2

12

14

VREF

13 14 15 16 17

15 16 17 18 19

AGND VREG PVIN1 PVINSYS PVIN2

Description Input Disconnect Switch Output for the Boost Regulator. Frequency Setting and Synchronization Input. To set the switching frequency to 2.4 MHz, pull the SYNC/FREQ pin high. To set the switching frequency to 1.2 MHz, pull the SYNC/FREQ pin low. To synchronize the switching frequency, connect the SYNC/FREQ pin to an external clock. Start-Up Sequence Control. For manual VPOS/VNEG startup using an individual precision enabling pin, leave the SEQ pin open. For simultaneous VPOS/VNEG startup when the EN2 pin rises, connect the SEQ pin to VREG (the EN1 pin can be used to enable the internal references early, if required). For a sequenced startup, pull the SEQ pin low. Either EN1 or EN2 can be used, and the corresponding supply is the first in sequence; hold the other enable pin low. Driver Stage Slew Rate Control. The SLEW pin sets the slew rate for the SW1 and SW2 drivers. For the fastest slew rate (best efficiency), leave the SLEW pin open. For normal slew rate, connect the SLEW pin to VREG. For the slowest slew rate (best noise performance), connect the SLEW pin to AGND. Feedback Input for the Boost Regulator. Connect a resistor divider between the positive side of the boost regulator output capacitor and AGND to program the output voltage. Error Amplifier Compensation for the Boost Regulator. Connect the compensation network between this pin and AGND. Boost Regulator Precision Enable. The EN1 pin is compared to an internal precision reference to enable the boost regulator output. Soft Start Programming. Leave the SS pin open to obtain the fastest soft start time. To program a slower soft start time, connect a resistor between the SS pin and AGND. Inverting Regulator Precision Enable. The EN2 pin is compared to an internal precision reference to enable the inverting regulator output. Error Amplifier Compensation for the Inverting Regulator. Connect the compensation network between this pin and AGND. Feedback Input for the Inverting Regulator. Connect a resistor divider between the negative side of the inverting regulator output capacitor and VREF to program the output voltage. Inverting Regulator Reference Output. Connect a 1.0 µF ceramic filter capacitor between the VREF pin and AGND. Analog Ground. Internal Regulator Output. Connect a 1.0 µF ceramic filter capacitor between the VREG pin and AGND. Power Input for the Boost Regulator. System Power Supply for the ADP5070. Power Input for the Inverting Regulator.

Rev. B | Page 6 of 27

Data Sheet Pin No. LFCSP TSSOP 18 20 19 1 20 2

ADP5070 Mnemonic SW2 PGND SW1 EPAD

Description Switching Node for the Inverting Regulator. Power Ground for the Boost and Inverting Regulators. Switching Node for the Boost Regulator. Exposed Pad. Connect the exposed pad to AGND.

Rev. B | Page 7 of 27

ADP5070

Data Sheet

TYPICAL PERFORMANCE CHARACTERISTICS Typical performance characteristics are generated using the standard bill of materials for each input/output combination listed in Table 9, Table 10, and Table 11. 700

350

600

IOUT(MAX) (mA)

250

400 300

100

50

0

10

20

30

40

50

VPOS (V)

Figure 4. Boost Regulator Maximum Output Current, fSW = 1.2 MHz, TA = 25°C, Based on Target of 70% ILIM (BOOST)

0 –40

–20

–10

0

Figure 7. Inverting Regulator Maximum Output Current, fSW = 1.2 MHz, TA = 25°C, Based on Target of 70% ILIM (INVERTER) 350

250

IOUT(MAX) (mA)

500

300

400 300

150 100

100

50

10

20

30

40

50

VPOS (V)

0 –40

12068-004

Figure 5. Boost Regulator Maximum Output Current, fSW = 2.4 MHz, TA = 25°C, Based on Target of 70% ILIM (BOOST)

–20

–10

0

VNEG (V)

Figure 8. Inverting Regulator Maximum Output Current, fSW = 2.4 MHz, TA = 25°C, Based on Target of 70% ILIM (INVERTER) 100

80

80

EFFICIENCY (%)

100

60

40

20

60

40

20 VIN = 3.3V, 1.2MHz VIN = 3.3V, 2.4MHz 0.01

0.1

1

LOAD (A)

12068-005

0 0.001

–30

0 0.001

VIN = 3.3V, 1.2MHz VIN = 3.3V, 2.4MHz 0.01

0.1

1

LOAD (A)

Figure 9. Inverting Regulator Efficiency vs. Current Load, VIN = 3.3 V, VNEG = −5 V, TA = 25°C

Figure 6. Boost Regulator Efficiency vs. Current Load, VIN = 3.3 V, VPOS = 5 V, TA = 25°C

Rev. B | Page 8 of 27

12068-008

0

12V, L = 15µH 5V, L = 15µH 5V, L = 10µH 3.3V, L = 10µH 15V, L = 6.8µH 12V, L = 6.8µH 15V, L = 15µH 3.3V, L = 6.8µH

200

200

0

VIN = VIN = VIN = VIN = VIN = VIN = VIN = VIN =

12068-007

VIN = 12V, L = 10µH VIN = 3.3V, L = 6.8µH VIN = 5V, L = 10µH VIN = 3.3V, L = 3.3µH VIN = 5V, L = 3.3µH VIN = 15V, L = 10µH

600

IOUT(MAX) (mA)

–30

VNEG (V)

700

EFFICIENCY (%)

5V, L = 15µH 3.3V, L = 10µH 15V, L = 15µH 15V, L = 22µH 12V, L = 15µH 12V, L = 22µH 3.3V, L = 6.8µH 5V, L = 10µH

150 100

0

VIN = VIN = VIN = VIN = VIN = VIN = VIN = VIN =

200

200

12068-003

IOUT(MAX) (mA)

500

300

12068-006

VIN = 5V, L = 10µH VIN = 3.3V, L = 6.8µH VIN = 5V, L = 6.8µH VIN = 3.3V, L = 4.7µH VIN = 12V, L = 15µH VIN = 15V, L = 15µH

ADP5070 100

80

80

60

40

20

VIN = 3.3V, 1.2MHz VIN = 3.3V, 2.4MHz VIN = 5V, 1.2MHz VIN = 5V, 2.4MHz 0.01

0.1

1

LOAD (A)

80

EFFICIENCY (%)

80

60

40

0.01

0.1

1

LOAD (A)

Figure 11. Boost Regulator Efficiency vs. Current Load, VPOS = 15 V, TA = 25°C

40

0 0.001

VIN = 3.3V, 1.2MHz VIN = 3.3V, 2.4MHz VIN = 5V, 1.2MHz VIN = 5V, 2.4MHz 0.01

0.1

1

LOAD (A)

Figure 14. Inverting Regulator Efficiency vs. Current Load, VNEG = −15 V, TA = 25°C 100

80

80

EFFICIENCY (%)

100

60

40

60

40

20

20 VIN = 5V, 1.2MHz VIN = 5V, 2.4MHz 0.01

0.1

1

LOAD (A)

Figure 12. Boost Regulator Efficiency vs. Current Load, VPOS = 34 V, TA = 25°C

0 0.001

12068-011

0 0.001

1

60

20

VIN = 3.3V, 1.2MHz VIN = 3.3V, 2.4MHz VIN = 5V, 1.2MHz VIN = 5V, 2.4MHz 12068-010

EFFICIENCY (%)

100

0 0.001

0.1 LOAD (A)

100

20

0.01

Figure 13. Inverting Regulator Efficiency vs. Current Load, VNEG = −9 V, TA = 25°C

Figure 10. Boost Regulator Efficiency vs. Current Load, VPOS = 9 V, TA = 25°C

EFFICIENCY (%)

0 0.001

VIN = 3.3V, 1.2MHz VIN = 3.3V, 2.4MHz VIN = 5V, 1.2MHz VIN = 5V, 2.4MHz

VIN = 5V, 1.2MHz VIN = 5V, 2.4MHz 0.01 LOAD (A)

0.1

12068-014

0 0.001

40

12068-013

20

60

12068-012

EFFICIENCY (%)

100

12068-009

EFFICIENCY (%)

Data Sheet

Figure 15. Inverting Regulator Efficiency vs. Current Load, VNEG = −34 V, TA = 25°C

Rev. B | Page 9 of 27

Data Sheet

100

100

80

80

EFFICIENCY (%)

60

40

40

20 TA = +125°C TA = +25°C TA = –40°C 0.01

0.1

1

LOAD (A)

0 0.001

12068-015

0 0.001

0.01

0.1

1

LOAD (A)

Figure 16. Boost Regulator Efficiency over Temperature, VIN = 5 V, VPOS = 15 V, fSW = 1.2 MHz

Figure 19. Inverting Regulator Efficiency over Temperature, VIN = 5 V, VNEG = −15 V, fSW = 1.2 MHz 0.5

0.3

0.1

–0.1

–0.3 VOUT ACCURACY VFB1 ACCURACY 0

5

10

15

20

VIN (V)

0.1

–0.1

–0.3 VOUT ACCURACY VREF ACCURACY VFB2 ACCURACY

–0.5

12068-016

–0.5

0.3

0

5

10

15

12068-019

VARIATION FROM NOMINAL (%)

0.5

20

VIN (V)

Figure 17. Boost Regulator Line Regulation, VPOS = 15 V, fSW = 1.2 MHz, 15 mA Load, TA = 25°C

Figure 20. Inverting Regulator Line Regulation, VNEG = −15 V, fSW = 1.2 MHz, 15 mA Load, TA = 25°C

0.5 LOAD REGULATION, CHANGE IN VFB2 (%)

0.5

0.3

0.1

–0.1

–0.3 1.2MHz 2.4MHz –0.5 0

0.05

0.10

0.15

0.20

0.25

LOAD (A)

Figure 18. Boost Regulator Load Regulation, VIN = 5 V, VPOS = 15 V

0.3

0.1

–0.1

–0.3 1.2MHz 2.4MHz –0.5

12068-017

LOAD REGULATION, CHANGE IN VFB1 (%)

TA = +125°C TA = +25°C TA = –40°C 12068-018

20

VARIATION FROM NOMINAL (%)

60

0

0.05 LOAD (A)

0.10

12068-020

EFFICIENCY (%)

ADP5070

Figure 21. Inverting Regulator Load Regulation, VIN = 5 V, VNEG = −15 V

Rev. B | Page 10 of 27

Data Sheet

ADP5070 0.5

0.1

–0.1

–0.3

–0.5 0

0.06

0.04

0.02

0.08

0.12

0.10

INVERTING REGULATOR LOAD (A)

Figure 22. Cross Regulation, Boost Regulator VFB1 Regulation over Inverting Regulator Current Load, VIN = 5 V, VPOS = 15 V, VNEG = -15 V, fSW = 2.4 MHz, TA = 25°C, Boost Regulator Run in Continuous Conduction Mode with Fixed Load for Test

0.3

0.1

–0.1

–0.3

–0.5 0.05

0

0.10

0.20

0.15

0.25

BOOST REGULATOR LOAD (A)

12068-024

VFB2 DEVIATION FROM AVERAGE VALUE (%)

0.3

12068-021

VFB1 DEVIATION FROM AVERAGE VALUE (%)

0.5

Figure 25. Cross Regulation, Inverting Regulator VFB2 Regulation over Boost Regulator Current Load, VIN = 5 V, VPOS = 15 V, VNEG = −15 V, fSW = 2.4 MHz, TA = 25°C, Inverting Regulator Run in Continuous Conduction Mode with Fixed Load for Test 0.72

1.20 TA = +125°C TA = +25°C TA = –40°C

1.18

TA = +125°C TA = +25°C TA = –40°C

0.70

1.16

0.68

1.12

ILIMIT (A)

ILIMIT (A)

1.14

1.10

0.66

1.08

0.64 1.06 1.04

0.62

0

2

4

6

8

10

12

14

16

VIN (V)

0.60

12068-022

1.00

Figure 23. Boost Regulator Current Limit (ILIMIT) vs. Input Voltage (VIN) over Temperature

0

4

6

8

10

12

14

16

VIN (V)

Figure 26. Inverting Regulator Current Limit (ILIMIT) vs. Input Voltage (VIN) over Temperature 1.27

2.54

2.49

OSCILLATOR FREQUENCY (MHz)

TA = +125°C TA = +25°C TA = –40°C

2.44

2.39

2.34

2.29

TA = +125°C TA = +25°C TA = –40°C

1.25 1.23 1.21 1.19 1.17

2.24 0

2

4

6

8 VIN (V)

10

12

14

16

1.13

Figure 24. Oscillator Frequency vs. Input Voltage (VIN) over Temperature, SYNC/FREQ Pin = High

0

2

4

6

8 VIN (V)

10

12

14

16

12068-026

1.15

12068-023

OSCILLATOR FREQUENCY (MHz)

2

12068-025

1.02

Figure 27. Oscillator Frequency vs. Input Voltage (VIN) over Temperature, SYNC/FREQ Pin = Low

Rev. B | Page 11 of 27

ADP5070

Data Sheet 5.0

12

10

8 6

4

2

0 0

2

4

6

8

10

12

14

16

VIN (V)

4.0 3.5 3.0 2.5 2.0 1.5 1.0 TA = +125°C TA = +25°C TA = –40°C

0.5 0

12068-027

TA = +125°C TA = +25°C TA = –40°C

4.5

0

2

4

6

8

10

12

14

16

VIN (V)

Figure 28. Shutdown Quiescent Current vs. Input Voltage (VIN) over Temperature, Both ENx Pins Below Shutdown Threshold

12068-030

OPERATING QUIESCENT CURRENT (mA)

Figure 31. Operating Quiescent Current vs. Input Voltage (VIN) over Temperature, Both ENx Pins On

T

T

VIN

VIN

VPOS

VNEG

2

2

1

1

VFB1

VFB2

3

B

CH1 1.0V BW CH2 100mV CH3 5.0mV BW

W

4.00ms T

CH1

5.00V

14.0ms

12068-028

3

CH1 1V BW

B

CH2 100mV

W

B

CH3 5mV

4.00ms T

W

CH1

5.0V

14.0ms

12068-031

SHUTDOWN QUIESCENT CURRENT (µA)

14

Figure 32. Inverting Regulator Line Transient, VIN = 4.5 V to 5.5 V Step, VNEG = −15 V, RLOAD2 = 300 Ω, fSW = 2.4 MHz, TA = 25°C

Figure 29. Boost Regulator Line Transient, VIN = 4.5 V to 5.5 V Step, VPOS = 15 V, RLOAD1 = 300 Ω, fSW = 2.4 MHz, TA = 25°C

T

T

ILOAD1 ILOAD2

1

VNEG

VPOS

2

2

1

VFB2 3

VFB1

CH3 25mV

B

W

B

W

4.00ms T

CH1

13.160ms

137mA

CH1 10mA

12068-029

CH2 50mV

CH1 20mA

CH3 5mV

Figure 30. Boost Regulator Load Transient, VIN = 5 V Step, VPOS = 15 V, ILOAD1 = 120 mA to 150 mA Step, fSW = 2.4 MHz, TA = 25°C

CH2 50mV B

W

B

W

4.00ms T

13.0ms

CH1

50mA

12068-032

3

Figure 33. Inverting Regulator Load Transient, VIN = 5 V Step, VNEG = −15 V, ILOAD2 = 35 mA to 45 mA Step, fSW = 2.4 MHz, TA = 25°C

Rev. B | Page 12 of 27

Data Sheet

ADP5070 T

T

IINDUCTOR IINDUCTOR 1

1

SW2

SW1 2

2

VNEG

VPOS 3

2.0µs

CH1

0.0A

T 34.6%

CH1 100mA BW CH2 5V Ω BW CH3 500mV BW

Figure 34. Boost Regulator Skip Mode Operation Showing Inductor Current (IINDUCTOR), Switch Node Voltage, and Output Ripple, VIN = 5 V, VPOS = 15 V, ILOAD1 = 4 mA, fSW = 2.4 MHz, TA = 25°C

CH1

2.0µs

0A

T 17.4%

12068-036

CH1 200mA BW CH2 2.5V Ω BW CH3 500mV BW

12068-033

3

Figure 37. Inverting Regulator Skip Mode Operation Showing Inductor Current (IINDUCTOR), Switch Node Voltage, and Output Ripple, VIN = 5 V, VNEG = −5 V, ILOAD2 = 1 mA, fSW = 2.4 MHz, TA = 25°C T

T

IINDUCTOR

IINDUCTOR 1

1

SW2

SW1

2

2

VNEG

VPOS

3

CH1

152mA

CH1 100mA BW CH2 5.0V Ω BW 100ns CH3 500mV BW T 17.4%

12068-034

CH1 200mA BW CH2 2.5V Ω BW 100ns CH3 500mV BW T 34.6%

Figure 35. Boost Regulator Discontinuous Conduction Mode Operation Showing Inductor Current (IINDUCTOR), Switch Node Voltage, and Output Ripple, VIN = 5 V, VPOS = 15 V, ILOAD1 = 35 mA, fSW = 2.4 MHz, TA = 25°C

CH1

80mA

12068-037

3

Figure 38. Inverting Regulator Discontinuous Conduction Mode Operation Showing Inductor Current (IINDUCTOR), Switch Node Voltage, and Output Ripple, VIN = 5 V, VNEG = −5 V, ILOAD2 = 6 mA, fSW = 2.4 MHz, TA = 25°C

T

T

IINDUCTOR 1

1

IINDUCTOR SW2

2

SW1 2

VNEG

3

VPOS

152mA

CH1 100mA BW CH2 5V Ω BW CH3 500mV BW

Figure 36. Boost Regulator Continuous Conduction Mode Operation Showing Inductor Current (IINDUCTOR), Switch Node Voltage, and Output Ripple, VIN = 5 V, VPOS = 15 V, ILOAD1 = 90 mA, fSW = 2.4 MHz, TA = 25°C

100ns T 17.4%s

CH1

172mA

12068-038

CH1

12068-035

CH1 200mA BW CH2 2.5V Ω BW 100ns CH3 500mV BW T 34.6%

3

Figure 39. Inverting Regulator Continuous Conduction Mode Operation Showing Inductor Current (IINDUCTOR), Switch Node Voltage, and Output Ripple, VIN = 5 V, VNEG = −5 V, ILOAD2 = 35 mA, fSW = 2.4 MHz, TA = 25°C

Rev. B | Page 13 of 27

ADP5070

Data Sheet

THEORY OF OPERATION VIN CVREG PVIN1

SYNC/FREQ

PVIN2

VREG

PVINSYS

CURRENT SENSE

INBK SWITCH CONTROL

HV REGULATOR

INVERTER PWM CONTROL

INBK

D2

SW2 L1 VOUT1

D1

EN1

SW1

SLEW

REF1

RC1

RFB2

INVERTER_ENABLE REF_1V6

+

THERMAL SHUTDOWN

1.5MΩ

COMP1

FB2

BOOST_ENABLE

SEQUENCE CONTROL

ERROR AMP

FB1 FB2

CC1 SLEW

EN1

COMP2

4µA OVP

EN2 SEQ

VREF CVREF

VREG

UVLO

RFT2

REF2



1.5MΩ

RFB1



ERROR AMP +

OSCILLATOR

CURRENT SENSE

FB1

COUT2

PLL

BOOST PWM CONTROL PGND

L2

EN2

COUT1 RFT1

SLEW

HV BAND GAP

START-UP TIMERS

REFERENCE GENERATOR

SS RSS (OPTIONAL)

REF1 REF2

RC2

REF_1V6 CC2 AGND

12068-039

CIN

Figure 40. Functional Block Diagram

PWM MODE The boost and inverting regulators in the ADP5070 operate at a fixed frequency set by an internal oscillator. At the start of each oscillator cycle, the MOSFET switch turns on, applying a positive voltage across the inductor. The inductor current (IINDUCTOR) increases until the current sense signal crosses the peak inductor current threshold that turns off the MOSFET switch; this threshold is set by the error amplifier output. During the MOSFET off time, the inductor current declines through the external diode until the next oscillator clock pulse starts a new cycle. It regulates the output voltage by adjusting the peak inductor current threshold.

PSM MODE During light load operation, the regulators can skip pulses to maintain output voltage regulation. Skipping pulses increases the device efficiency.

UNDERVOLTAGE LOCKOUT (UVLO) The undervoltage lockout circuitry monitors the PVINSYS pin voltage level. If the input voltage drops below the VUVLO_FALLING threshold, both regulators turn off. After the PVINSYS pin voltage rises above the VUVLO_RISING threshold, the soft start period initiates, and the regulators are enabled.

OSCILLATOR AND SYNCHRONIZATION The ADP5070 initiates the drive of the boost regulator SW1 pin and the inverting regulator SW2 pin 180° out of phase to reduce peak current consumption and noise.

A phase-locked loop (PLL)-based oscillator generates the internal clock and offers a choice of two internally generated frequency options or external clock synchronization. The switching frequency is configured using the SYNC/FREQ pin options shown in Table 6. For external synchronization, connect the SYNC/FREQ pin to a suitable clock source. The PLL locks to an input clock within the range specified by fSYNC. Table 6. SYNC/FREQ Pin Options SYNC/FREQ Pin High Low External Clock

Switching Frequency 2.4 MHz 1.2 MHz 1 × clock frequency

INTERNAL REGULATORS The internal VREG regulator in the ADP5070 provides a stable power supply for the internal circuitry. The VREG supply can be used to provide a logic high signal for device configuration pins but must not be used to supply external circuitry. The VREF regulator provides a reference voltage for the inverting regulator feedback network to ensure a positive feedback voltage on the FB2 pin. A current-limit circuit is included for both regulators to protect the circuit from accidental loading.

Rev. B | Page 14 of 27

Data Sheet

ADP5070

PRECISION ENABLING

CURRENT-LIMIT PROTECTION

The ADP5070 has an individual enable pin for the boost and inverting regulators: EN1 and EN2. The enable pins feature a precision enable circuit with an accurate reference voltage. This reference allows the ADP5070 to be sequenced easily from other supplies. It can also be used as a programmable UVLO input by using a resistor divider.

The boost and inverting regulators in the ADP5070 include current-limit protection circuitry to limit the amount of forward current through the MOSFET switch.

The enable pins have an internal pull-down resistor that defaults each regulator to off when the pin is floating. When the voltage at the enable pins is greater than the VTH_H reference level, the regulator is enabled.

When the peak inductor current exceeds the overcurrent limit threshold for a number of clock cycles during an overload or short-circuit condition, the regulator enters hiccup mode. The regulator stops switching and then restarts with a new soft start cycle after tHICCUP and repeats until the overcurrent condition is removed.

OVERVOLTAGE PROTECTION

SOFT START Each regulator in the ADP5070 includes soft start circuitry that ramps the output voltage in a controlled manner during startup, thereby limiting the inrush current. The soft start time is internally set to the fastest rate when the SS pin is open. Connecting a resistor between SS and AGND allows the adjustment of the soft start delay. The delay length is common to both regulators.

SLEW RATE CONTROL The ADP5070 employs programmable output driver slew rate control circuitry. This circuitry reduces the slew rate of the switching node as shown in Figure 41, resulting in reduced ringing and lower EMI. To program the slew rate, connect the SLEW pin to the VREG pin for normal mode, to the AGND pin for slow mode, or leave it open for fast mode. This configuration allows the use of an open-drain output from a noise sensitive device to switch the slew rate from fast to slow, for example, during analog-to-digital converter (ADC) sampling. Note that slew rate control causes a trade-off between efficiency and low EMI.

An overvoltage protection mechanism is present on the FB1 and FB2 pins for the boost and inverting regulators. On the boost regulator, when the voltage on the FB1 pin exceeds the VOV1 threshold, the switching on SW1 stops until the voltage falls below the threshold again. This functionality is permanently enabled on this regulator. On the inverting regulator, when the voltage on the FB2 pin drops below the VOV2 threshold, the switching stops until the voltage rises above the threshold. This functionality is enabled after the soft start period has elapsed.

THERMAL SHUTDOWN In the event that the ADP5070 junction temperature rises above TSHDN, the thermal shutdown circuit turns off the IC. Extreme junction temperatures can be the result of prolonged high current operation, poor circuit board design, and/or high ambient temperature. Hysteresis is included so that when thermal shutdown occurs, the ADP5070 does not return to operation until the onchip temperature drops below TSHDN minus THYS. When resuming from thermal shutdown, a soft start is performed on each enabled channel.

START-UP SEQUENCE The ADP5070 implements a flexible start-up sequence to meet different system requirements. Three different enabling modes can be implemented via the SEQ pin, as explained in Table 7.

FASTEST

Table 7. SEQ Pin Settings

12068-040

SLOWEST

Figure 41. Switching Node at Various Slew Rate Settings

SEQ Pin Open VREG Low

Description Manual enable mode Simultaneous enable mode Sequential enable mode

To configure the manual enable mode, leave the SEQ pin open. The boost and inverting regulators are controlled separately from their respective precision enable pins.

Rev. B | Page 15 of 27

ADP5070

Data Sheet

To configure the simultaneous enable mode, connect the SEQ pin to the VREG pin. Both regulators power up simultaneously when the EN2 pin is taken high. The EN1 pin enable can be used to enable the internal references ahead of enabling the outputs, if desired. The simultaneous enable mode timing is shown in Figure 42.

VPOS

VIN DISCONNECT SWITCH TURN ON

VPOS

TIME

VNEG 1. VPOS FOLLOWED BY VNEG (SEQ = LOW, EN1 = HIGH, EN2 = LOW)

VIN DISCONNECT SWITCH TURN ON

VPOS TIME

VIN DISCONNECT SWITCH TURN ON

SIMULTANEOUS ENABLE MODE (SEQ = HIGH, EN2 = HIGH)

12068-041

VNEG

TIME

Figure 42. Simultaneous Enable Mode

Rev. B | Page 16 of 27

VNEG 2. VNEG FOLLOWED BY VPOS (SEQ = LOW, EN2 = HIGH, EN1 = LOW) SEQUENTIAL ENABLE MODE

Figure 43. Sequential Enable Mode

12068-042

To configure the sequential enable mode, pull the SEQ pin low. In this mode, either VPOS or VNEG can be enabled first by using the respective EN1 pin or EN2 pin. Keep the other pin low. The secondary supply is enabled when the primary supply completes soft start and its feedback voltage reaches approximately 85% of the target value. The sequential enable mode timing is shown in Figure 43.

Data Sheet

ADP5070

APPLICATIONS INFORMATION ADIsimPOWER DESIGN TOOL

Set the positive output for the boost regulator by

The ADP5070 is supported by the ADIsimPower design toolset. ADIsimPower is a collection of tools that produce complete power designs optimized to a specific design goal. These tools allow the user to generate a full schematic, bill of materials, and calculate performance in minutes. ADIsimPower can optimize designs for cost, area, efficiency, and parts count while taking into consideration the operating conditions and limitations of the IC and all real external components. The ADIsimPower tool can be found at www.analog.com/adisimpower, and the user can request an unpopulated board through the tool.

 RFT1   VPOS = VFB1 × 1 +  R FB1   where: VPOS is the positive output voltage. VFB1 is the FB1 reference voltage. RFT1 is the feedback resistor from VPOS to FB1. RFB1 is the feedback resistor from FB1 to AGND. Set the negative output for the inverting regulator by

COMPONENT SELECTION

VNEG = VFB2 −

Feedback Resistors The ADP5070 provides an adjustable output voltage for both boost and inverting regulators. An external resistor divider sets the output voltage where the divider output must equal the appropriate feedback reference voltage, VFB1 or VFB2. To limit the output voltage accuracy degradation due to feedback bias current, ensure that the current through the divider is at least 10 times IFB1 or IFB2.

RFT2 (VREF − VFB2 ) RFB2

where: VNEG is the negative output voltage. VFB2 is the FB2 reference voltage. RFT2 is the feedback resistor from VNEG to FB2. RFB2 is the feedback resistor from FB2 to VREF. VREF is the VREF pin reference voltage.

Table 8. Recommended Feedback Resistor Values Desired Output Voltage (V) ±1.8 ±3 ±3.3 ±4.2 ±5 ±9 ±12 ±13 ±15 ±18 ±20 ±24 ±30 ±35

RFT1 (MΩ) 0.143 0.316 0.357 0.432 0.604 1.24 1.4 2.1 2.43 2.15 2.55 3.09 3.65 5.9

Boost/SEPIC Regulator Calculated RFB1 (kΩ) Output Voltage (V) 115 1.795 115 2.998 115 3.283 102 4.188 115 5.002 121 8.998 100 12.000 137 13.063 137 14.990 100 18.000 107 19.865 107 23.903 100 30.000 137 35.253

Rev. B | Page 17 of 27

RFT2 (MΩ) 0.332 0.475 0.523 0.715 1.15 1.62 1.15 2.8 2.32 2.67 2.94 3.16 4.12 5.11

Inverting Regulator Calculated RFB2 (kΩ) Output Voltage (V) 102 −1.804 100 −3.000 102 −3.302 115 −4.174 158 −5.023 133 −8.944 71.5 −12.067 162 −13.027 118 −14.929 113 −18.103 113 −20.014 102 −23.984 107 −30.004 115 −34.748

ADP5070

Data Sheet

Output Capacitors

VREG Capacitor

Higher output capacitor values reduce the output voltage ripple and improve load transient response. When choosing this value, it is also important to account for the loss of capacitance due to the output voltage dc bias.

A 1.0 µF ceramic capacitor (CVREG) is required between the VREG pin and AGND.

Calculate the worst-case capacitance accounting for capacitor variation over temperature, component tolerance, and voltage using the following equation: CEFFECTIVE = CNOMINAL × (1 − TEMPCO) × (1 − DCBIASCO) × (1 − Tolerance)

A 1.0 µF ceramic capacitor (CVREF) is required between the VREF pin and AGND.

Soft Start Resistor A resistor can be connected between the SS pin and the AGND pin to increase the soft start time. The soft start time can be set by the resistor between 4 ms (268 kΩ) and 32 ms (50 kΩ). Leaving the SS pin open selects the fastest time of 4 ms. Figure 44 shows the behavior of this operation. Calculate the soft start time using the following formula: tSS = 38.4 × 10−3 − 1.28 × 10−7 × RSS (Ω) where 50 kΩ ≤ RSS ≤ 268 kΩ. SOFT START TIMER

32ms

where: CEFFECTIVE is the effective capacitance at the operating voltage. CNOMINAL is the nominal data sheet capacitance. TEMPCO is the worst-case capacitor temperature coefficient. DCBIASCO is the dc bias derating at the output voltage. Tolerance is the worst-case component tolerance. To guarantee the performance of the device, it is imperative that the effects of dc bias, temperature, and tolerances on the behavior of the capacitors be evaluated for each application. Capacitors with lower effective series resistance (ESR) and effective series inductance (ESL) are preferred to minimize output voltage ripple. Note that the use of large output capacitors can require a slower soft start to prevent current limit during startup. A 10 µF capacitor is suggested as a good balance between performance and size.

Input Capacitor Higher value input capacitors help to reduce the input voltage ripple and improve transient response. To minimize supply noise, place the input capacitor as close as possible to the PVINSYS pin, PVIN1 pin, and PVIN2 pin. A low ESR capacitor is recommended. The effective capacitance needed for stability is a minimum of 10 µF. If the power pins are individually decoupled, it is recommended to use an effective minimum of a 5.6 µF capacitor on the PVIN1 and PVIN2 pins and a 3.3 µF capacitor on the PVINSYS pin. The minimum values specified exclude dc bias, temperature, and tolerance effects that are application dependent and must be taken into consideration.

4ms

SS PIN OPEN R2

R1

SOFT START RESISTOR

12068-043

Ceramic capacitors are manufactured with a variety of dielectrics, each with a different behavior over temperature and applied voltage. Capacitors must have a dielectric adequate to ensure the minimum capacitance over the necessary temperature range and dc bias conditions. X5R or X7R dielectrics with a voltage rating of 25 V or 50 V (depending on output) are recommended for best performance. Y5V and Z5U dielectrics are not recommended for use with any dc-to-dc converter because of their poor temperature and dc bias characteristics.

VREF Capacitor

Figure 44. Soft Start Behavior

Diodes A Schottky diode with low junction capacitance is recommended for D1 and D2. At higher output voltages and especially at higher switching frequencies, the junction capacitance is a significant contributor to efficiency. Higher capacitance diodes also generate more switching noise. As a guide, a diode with less than 40 pF junction capacitance is preferred when the output voltage is above 5 V.

Inductor Selection for the Boost Regulator The inductor stores energy during the on time of the power switch, and transfers that energy to the output through the output rectifier during the off time. To balance the tradeoffs between small inductor current ripple and efficiency, inductance values in the range of 1 µH to 22 µH are recommended. In general, lower inductance values have higher saturation current and lower series resistance for a given physical size. However, lower inductance results in a higher peak current that can lead to reduced efficiency and greater input and/or output ripple and noise. A peakto-peak inductor ripple current close to 30% of the maximum dc input current for the application typically yields an optimal compromise.

Rev. B | Page 18 of 27

Data Sheet

ADP5070

For the inductor ripple current in continuous conduction mode (CCM) operation, the input (VIN) and output (VPOS) voltages determine the switch duty cycle (DUTY1) by

 V − VIN + VDIODE1   DUTY1 =  POS  VPOS + VDIODE1    where VDIODE1 is the forward voltage drop of the Schottky diode (D1). The dc input current in CCM (IIN) can be determined by the following equation:

I IN =

I OUT1 (1 − DUTY1)

Using the duty cycle (DUTY1) and switching frequency (fSW), determine the on time (tON1) using the following equation:

t ON1 =

DUTY1 f SW

Inductor Selection for the Inverting Regulator The inductor stores energy during the on time of the power switch, and transfers that energy to the output through the output rectifier during the off time. To balance the tradeoffs between small inductor current ripple and efficiency, inductance values in the range of 1 µH to 22 µH are recommended. In general, lower inductance values have higher saturation current and lower series resistance for a given physical size. However, lower inductance results in a higher peak current that can lead to reduced efficiency and greater input and/or output ripple and noise. A peak-to-peak inductor ripple current close to 30% of the maximum dc current in the inductor typically yields an optimal compromise. For the inductor ripple current in continuous conduction mode (CCM) operation, the input (VIN) and output (VNEG) voltages determine the switch duty cycle (DUTY2) by

  | VNEG | + VDIODE2  DUTY2 =   V + | V | + VDIODE2  IN NEG  

The inductor ripple current (∆IL1) in steady state is calculated by

∆I L1 =

where VDIODE2 is the forward voltage drop of the Schottky diode (D2).

VIN × tON1 L1

The dc current in the inductor in CCM (IL2) can be determined by the following equation:

Solve for the inductance value (L1) using the following equation:

L1 =

VIN × tON1 ∆I L1

Assuming an inductor ripple current of 30% of the maximum dc input current results in

L1 =

I OUT2 (1 − DUTY2)

I L2 =

Using the duty cycle (DUTY2) and switching frequency (fSW), determine the on time (tON2) by the following equation:

VIN × t ON1 × (1 − DUTY1)

t ON2 =

0.3 × IOUT1

Ensure that the peak inductor current (the maximum input current plus half the inductor ripple current) is below the rated saturation current of the inductor. Likewise, ensure that the maximum rated rms current of the inductor is greater than the maximum dc input current to the regulator. When the ADP5070 boost regulator is operated in CCM at duty cycles greater than 50%, slope compensation is required to stabilize the current mode loop. This slope compensation is built in to the ADP5070. For stable current mode operation, ensure that the selected inductance is equal to or greater than the minimum calculated inductance, LMIN1, for the application parameters in the following equation:

  0.27 − 0.33  (µH) L1 > L MIN1 = VIN ×   (1 − DUTY1)    Table 10 suggests a series of inductors to use with the ADP5070 boost regulator.

DUTY2 f SW

The inductor ripple current (∆IL2) in steady state is calculated by

∆I L2 =

VIN × t ON2 L2

Solve for the inductance value (L2) by the following equation:

L2 =

VIN × tON2 ∆I L2

Assuming an inductor ripple current of 30% of the maximum dc current in the inductor results in

L2 =

VIN × t ON2 × (1 − DUTY2) 0.3 × IOUT2

Ensure that the peak inductor current (the maximum input current plus half the inductor ripple current) is below the rated saturation current of the inductor. Likewise, ensure that the maximum rated rms current of the inductor is greater than the maximum dc input current to the regulator.

Rev. B | Page 19 of 27

ADP5070

Data Sheet

When the ADP5070 inverting regulator is operated in CCM at duty cycles greater than 50%, slope compensation is required to stabilize the current mode loop. For stable current mode operation, ensure that the selected inductance is equal to or greater than the minimum calculated inductance, LMIN2, for the application parameters in the following equation:

  0.27 L2 > L MIN2 = VIN ×  − 0.33  (µH)  (1 − DUTY2)    Table 11 suggests a series of inductors to use with the ADP5070 inverting regulator.

LOOP COMPENSATION The ADP5070 uses external components to compensate the regulator loop, allowing the optimization of the loop dynamics for a given application. It is recommended to use the ADIsimPower tool to calculate compensation components.

ZCOMP1 is the impedance of the series RC network from COMP1 to AGND. GCS1 is the current sense transconductance gain (the inductor current divided by the voltage at COMP1), which is internally set by the ADP5070 and is 6.25 A/V. ZOUT1 is the impedance of the load in parallel with the output capacitor. To determine the crossover frequency (fC1), it is important to note that, at that frequency, the compensation impedance (ZCOMP1) is dominated by a resistor (RC1), and the output impedance (ZOUT1) is dominated by the impedance of an output capacitor (COUT1). Therefore, when solving for the crossover frequency, the equation (by definition of the crossover frequency) is simplified to

AVL1 =

1 2π × f C1 × COUT1

Boost Regulator The boost converter produces an undesirable right half plane zero in the regulation feedback loop. This feedback loop requires compensating the regulator such that the crossover frequency occurs well below the frequency of the right half plane zero. The right half plane zero is determined by the following equation:

RLOAD1 (1 − DUTY1)2 2π × L1

where fC1 is the crossover frequency. To solve for RC1, use the following equation: RC1 =

2π × f C1 × COUT1 × (VPOS ) 2 VFB1 × VIN × GM1 × GCS1

where GCS1 = 6.25 A/V. Using typical values for VFB1 and GM1 results in

where: fZ1(RHP) is the right half plane zero frequency. RLOAD1 is the equivalent load resistance or the output voltage divided by the load current.

RC1 =

4188 × f C1 × COUT1 × (VPOS )2 VIN

For better accuracy, it is recommended to use the value of output capacitance, COUT1, expected for the dc bias conditions under which it operates under in the calculation for RC1.

 V − VIN + VDIODE1   DUTY1 =  POS  VPOS + VDIODE1    where VDIODE1 is the forward voltage drop of the Schottky diode (D1). To stabilize the regulator, ensure that the regulator crossover frequency is less than or equal to one-tenth of the right half plane zero frequency.

After the compensation resistor is known, set the zero formed by the compensation capacitor and resistor to one-fourth of the crossover frequency, or

CC1 =

2 π × f C1 × RC1

where CC1 is the compensation capacitor value.

The boost regulator loop gain is

AVL1 =

=1

FB1

V VFB1 × IN × G M1 × ROUT1|| Z COMP1 × VPOS VPOS

ERROR AMPLIFIER COMP1 gM1

REF1

GCS1 × Z OUT1

RC1

CB1

CC1

where: AVL1 is the loop gain. VFB1 is the feedback regulation voltage VPOS is the regulated positive output voltage. VIN is the input voltage. GM1 is the error amplifier transconductance gain. ROUT1 is the output impedance of the error amplifier and is 33 MΩ.

12068-044

f Z1 (RHP ) =

VFB1 VIN × × GM1 × RC1 × GCS1 × VPOS VPOS

Figure 45. Compensation Components

The capacitor, CB1, is chosen to cancel the zero introduced by the output capacitor ESR. Solve for CB1 as follows:

Rev. B | Page 20 of 27

CB1 =

ESR × COUT1 RC1

Data Sheet

ADP5070

For low ESR output capacitance such as with a ceramic capacitor, CB1 is optional. For optimal transient performance, RC1 and CC1 may need to be adjusted by observing the load transient response of the ADP5070. For most applications, RC1 must be within the range of 1 kΩ to 200 kΩ, and CC1 must be within the range of 1 nF to 68 nF.

To determine the crossover frequency, it is important to note that, at that frequency, the compensation impedance (ZCOMP2) is dominated by a resistor, RC2, and the output impedance (ZOUT2) is dominated by the impedance of the output capacitor, COUT2. Therefore, when solving for the crossover frequency, the equation (by definition of the crossover frequency) is simplified to

VIN VFB2 × × G M2 × |VNEG| (VIN + 2 × | VNEG|) 1 RC2 × GCS 2 × =1 2π × f C2 × COUT2

Inverting Regulator The inverting converter, like the boost converter, produces an undesirable right half plane zero in the regulation feedback loop. This feedback loop requires compensating the regulator such that the crossover frequency occurs well below the frequency of the right half plane zero. The right half plane zero frequency is determined by the following equation: f Z2(RHP) =

where fC2 is the crossover frequency. To solve for RC2, use the following equation:

RLOAD2( 1 − DUTY2) 2π × L2 × DUTY2

2

RC2 =

where: fZ2(RHP) is the right half plane zero frequency. RLOAD2 is the equivalent load resistance or the output voltage divided by the load current.

2π × f C2 × COUT2 × |VNEG| × (VIN + (2 × | VNEG|) VFB2 × VIN × G M2 × GCS2

where GCS2 = 6.25 A/V. Using typical values for VFB2 and GM2 results in

RC2 =

 |VNEG| + VDIODE2   DUTY2 =   V + |V | + VDIODE2  NEG  IN  where VDIODE2 is the forward voltage drop of the Schottky diode (D2). To stabilize the regulator, ensure that the regulator crossover frequency is less than or equal to one-tenth of the right half plane zero frequency. The regulator loop gain is

AVL2

AVL2 =

4188 × f C2 × COUT 2 × | VNEG| × (VIN + (2 × | VNEG|) VIN

For better accuracy, it is recommended to use the value of output capacitance, COUT2, expected under the dc bias conditions that it operates under in the calculation for RC2. After the compensation resistor is known, set the zero formed by the CC2 and RC2 to one-fourth of the crossover frequency, or

CC2 =

2 π × f C2 × RC2

where CC2 is the compensation capacitor.

V VIN = FB2 × × GM2 × |VNEG| (VIN + 2 × | VNEG|)

FB2

ERROR AMPLIFIER COMP2 gM2

where: AVL2 is the loop gain. VFB2 is the feedback regulation voltage. VNEG is the regulated negative output voltage. VIN is the input voltage. GM2 is the error amplifier transconductance gain. ROUT2 is the output impedance of the error amplifier and is 33 MΩ. ZCOMP2 is the impedance of the series RC network from COMP2 to AGND. GCS2 is the current sense transconductance gain (the inductor current divided by the voltage at COMP2), which is internally set by the ADP5070 and is 6.25 A/V. ZOUT2 is the impedance of the load in parallel with the output capacitor.

RC2

CB2

CC2

12068-045

REF2

ROUT2|| Z COMP2 × GCS2 × ZOUT2

Figure 46. Compensation Component

The capacitor, CB2, is chosen to cancel the zero introduced by output capacitance, ESR. Solve for CB2 as follows:

CB2 =

ESR × C OUT2 RC2

For low ESR output capacitance, such as with a ceramic capacitor, CB2 is optional. For optimal transient performance, RC2 and CC2 may need to be adjusted by observing the load transient response of the ADP5070. For most applications, RC2 must be within the range of 1 kΩ to 200 kΩ, and CC2 must be within the range of 1 nF to 68 nF.

Rev. B | Page 21 of 27

ADP5070

Data Sheet

COMMON APPLICATIONS

Figure 47 shows the schematic referenced by Table 9 through Table 11 with example component values for +5 V to ±15 V generation. Table 9 shows the components common to all of the VIN and VOUT conditions.

Table 9 through Table 11 list a number of common component selections for typical VIN and VOUT conditions. These have been bench tested and provide an off the shelf solution. Note that when pairing a boost and inverting regulator bill of materials, choose the same VIN and switching frequency. To optimize components for an application, it is recommend to use the ADIsimPower toolset.

Table 9. Recommended Common Components Selections REF CIN1 CVREG CVREF

Value 10 µF 1 µF 1 µF

Part Number TMK316B7106KL-TD GRM188R71A105KA61D GRM188R71A105KA61D

ADP5070 SS

INBK

CC1 47nF

VREG VIN +5V

CIN1 10µF

RC2 15kΩ CC2 68nF

VPOS +15V

SW1

EN1

CVREG 1µF

L1 6.8µH D1 DFLS240

COMP1

FB1

RFT1 2.43MΩ RFB1 137kΩ

PVIN1 PVIN2 PVINSYS

PGND

EN2

VREF

CVREF 1µF RFB2 118kΩ

COMP2 SYNC/FREQ SLEW SEQ AGND

FB2

COUT2 10µF

RFT2 2.32MΩ

SW2 D2 DFLS240 L2 15µH

Figure 47. Typical +5 V to ±15 V Application

Rev. B | Page 22 of 27

COUT1 10µF

VNEG –15V

12068-046

RC1 12kΩ

Manufacturer Taiyo Yuden Murata Murata

Data Sheet

ADP5070

Table 10. Recommended Boost Regulator Components VIN (V) 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 5 5 5 5 5 5 5 5 12 12

VPOS (V) 5 5 9 9 15 15 24 24 34 34 9 9 15 15 24 24 34 34 24 24

Freq. (MHz) 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4

L1 (µH) 3.3 2.2 4.7 2.2 6.8 4.7 6.8 6.8 6.8 10 4.7 3.3 6.8 3.3 10 4.7 10 10 15 6.8

L1 Manufacturer Part Number Wurth Coilcraft® Elektronik XAL4030-332ME_ XAL4020-222ME_ 74438356022 XAL4030-472ME_ 74438357047 XAL4020-222ME_ 74438356022 XAL4030-682ME_ 74438357068 XAL4030-472ME_ 74438357047 XAL4030-682ME_ 74438357068 XAL4030-682ME_ 74438357068 XAL4030-682ME_ 74438357068 XAL4040-103ME_ XAL4030-472ME_ 74438357047 XAL4030-332ME_ XAL4030-682ME_ 74438357068 XAL4030-332ME_ XAL4040-103ME_ XAL4030-472ME_ 74438357047 XAL4040-103ME_ XAL4040-103ME_ XAL4040-153ME_ XAL4030-682ME_ 74438357068

COUT1 (µF) 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

COUT1, Murata Part GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L

D1, Diodes, Inc. Part DFLS240L DFLS240L DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240

RFT1 (MΩ) 0.604 0.604 1.24 1.24 2.43 2.43 3.09 3.09 4.22 4.22 1.24 1.24 2.43 2.43 3.09 3.09 4.22 4.22 3.09 3.09

RFB1 (kΩ) 115 115 121 121 137 137 107 107 102 102 121 121 137 137 107 107 102 102 107 107

CC1 (nF) 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47 47

RC1 (kΩ) 4.7 4.7 6.8 6.8 22 25 33 33 27 27 3.3 3.9 12 15 18 18 18 18 12 12

CC2 (nF) 47 47 47 47 47 47 47 47 47 47 47 47 68 47 47 47 47 47 47 47

RC2 (kΩ) 4.7 6.8 8.2 8.2 12 18 22 33 47 47 8.2 8.2 15 22 22 22 39 39 10 10

Table 11. Recommended Inverting Regulator Components VIN (V) 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 5 5 5 5 5 5 5 5 12 12

VNEG (V) −5 −5 −9 −9 −15 −15 −24 −24 −34 −34 −9 −9 −15 −15 −24 −24 −34 −34 −24 −24

Freq. (MHz) 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4 1.2 2.4

L2 (µH) 6.8 4.7 10 4.7 10 4.7 10 6.8 10 10 10 6.8 15 6.8 15 6.8 15 10 22 15

L2, Manufacturer Part Number Wurth Coilcraft Elektronik XAL4030-682ME_ 74438357068 XAL4030-472ME_ 74438357047 XAL4040-103ME_ XAL4030-472ME_ 74438357047 XAL4040-103ME_ XAL4030-472ME_ 74438357047 XAL4040-103ME_ XAL4030-682ME_ 74438357068 XAL4040-103ME_ XAL4040-103ME_ XAL4040-103ME_ XAL4030-682ME_ 74438357068 XAL4040-153ME_ XAL4030-682ME_ 74438357068 XAL4040-153ME_ XAL4030-682ME_ 74438357068 XAL4040-153ME_ XAL4040-103ME_ XAL5050-223ME_ XAL4040-153ME_

COUT2 (µF) 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

COUT2, Murata Part GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L GRM32ER71H106KA12L

Rev. B | Page 23 of 27

D2, Diodes, Inc. Part DFLS240L DFLS240L DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240 DFLS240

RFT2 (MΩ) 1.15 1.15 1.62 1.62 2.32 2.32 3.16 3.16 4.99 4.99 1.62 1.62 2.32 2.32 3.16 3.16 4.99 4.99 3.16 3.16

RFB2 (kΩ) 158 158 133 133 118 118 102 102 115 115 133 133 118 118 102 102 115 115 102 102

ADP5070

Data Sheet

SUPER LOW NOISE WITH OPTIONAL LDOS Low dropout regulators (LDOs) can be added to the ADP5070 output to provide super low noise supplies for high performance ADCs, digital-to-analog converters (DACs), and other precision applications. Table 12 shows recommended companion devices, and Figure 48 shows a typical application schematic for ±15 V generation from a +5 V supply. ADP5070 SS

INBK

D1 DFLS240

COMP1 CC1 47nF

FB1

VREG VIN +5V

CIN1 10µF

RC2 12kΩ CC2 47nF

RFT1 2.15MΩ RFB1 113kΩ

PVIN1 PVIN2 PVINSYS

PGND

EN2

VREF

VOUT ADJ (5V)

COUT1 10µF

SS

VPOS = +15V RFT3 20kΩ RFB3 10kΩ

CNR3 1µF RNR3 1kΩ

COUT3 2.2µF

GND CSS3 1nF

CVREF 1µF

FB2

SYNC/FREQ SLEW SEQ AGND

CIN3 1µF

VIN

EN

ADP7182 COUT2 10µF

RFB2 100kΩ COMP2

ADP7142

+16V

SW1

EN1

CVREG 1µF

L1 3.3µH

RFT2 2.1MΩ

SW2

EN

VOUT ADJ

–16V

D2 DFLS240

CIN4 2.2µF

VIN GND

VNEG = –15V RFT4 52.3kΩ RFB4 59kΩ

CNR4 47µF RNR4 5.9kΩ

COUT4 2.2µF

12068-047

RC1 5.6kΩ

L2 6.8µH

Figure 48. Super Low Noise ±15 V Generation with Post Regulation by the ADP7142 (+40 V, +200 mA, Low Noise LDO) and ADP7182 (−28 V, −200 mA, Low Noise LDO)

Table 12. Recommended LDOs for Super Low Noise Operation Parameter VIN Range Fixed VOUT Adjustable VOUT IOUT IQ at No Load ISHDN Typical Soft Start PGOOD Noise (Fixed), 10 Hz to 100 kHz PSRR (100 kHz) PSRR (1 MHz) Package

ADP7102 3.3 V to 20 V 1.5 V to 9 V 1.22 V to 19 V 300 mA 400 µA 40 µA No Yes 15 µV rms

ADP7104 3.3 V to 20 V 1.5 V to 9 V 1.22 V to 19 V 500 mA 400 µA 40 µA No Yes 15 µV rms

ADP7105 3.3 V to 20 V 1.8 V, 3.3 V, 5 V 1.22 V to 19 V 500 mA 400 µA 40 µA Yes Yes 15 µV rms

ADP7118 2.7 V to 20 V 1.2 V to 5 V 1.2 V to 19 V 200 mA 50 µA 2 µA Yes No 11 µV rms

ADP7142 2.7 V to 40 V 1.2 V to 5 V 1.2 V to 39 V 200 mA 50 µA 2 µA Yes No 11 µV rms

ADP7182 −2.7 V to −28 V −1.8 V to −5 V −1.22 V to−27 V −200 mA −33 µA −2 µA No No 18 µV rms

60 dB 40 dB 8-lead LFCSP, 8-lead SOIC

60 dB 40 dB 8-lead LFCSP, 8-lead SOIC

60 dB 40 dB 8-lead LFCSP, 8-lead SOIC

68 dB 50 dB 6-lead LFCSP, 8-lead SOIC, 5-lead TSOT

68 dB 50 dB 6-lead LFCSP, 8-lead SOIC, 5-lead TSOT

45 dB 45 dB 6-lead LFCSP, 8-lead LFCSP, 5-lead TSOT

Rev. B | Page 24 of 27

Data Sheet

ADP5070

SEPIC STEP-UP/STEP-DOWN OPERATION SEPIC operation allows the positive output channel to produce a voltage higher or lower than VIN. Both standalone and coupled inductors are supported for this application. SEPIC designs are supported in the ADIsimPower toolset.

ADP5070 SS

INBK

RC1

L1A

L1B

STANDALONE OR COUPLED-INDUCTOR

COMP1 +5V/400mA

CC1

SW1 CS1 RFT1

CVREG VREG 1µF VIN = +12V

CIN1 10µF

D1

FB1

COUT1

RFB1

PVIN1 PVIN2 PVINSYS

PGND

EN2

VREF

CVREF RFB2 1µF

RC2 COMP2

FB2

CC2 SYNC/FREQ SLEW SEQ AGND

COUT2

RFT2

SW2 D2

–5V/400mA

L2

Figure 49. SEPIC Application for +12 V in to ±5 V Output Generation

Rev. B | Page 25 of 27

12068-048

EN1

ADP5070

Data Sheet

LAYOUT CONSIDERATIONS

16mm







• •





12068-049



Keep the input bypass capacitor, CIN1, close to the PVIN1 pin, the PVIN2 pin, and the PVINSYS pin. Route each of these pins individually to the pad of this capacitor to minimize noise coupling between the power inputs rather than connecting the three pins at the device. A separate capacitor can be used on the PVINSYS pin for the best noise performance. Keep the high current paths as short as possible. These paths include the connections between CIN1, L1, L2, D1, D2, COUT1, COUT2, and PGND and their connections to the ADP5070. Keep AGND and PGND separate on the top layer of the board. This separation avoids pollution of AGND with switching noise. Do not connect PGND to the EPAD on the top layer of the layout. Connect both AGND and PGND to the board ground plane with vias. Ideally, connect PGND to the plane at a point between the input and output capacitors. Connect the EPAD on its own to this ground layer with vias and connect AGND as near to the pin as possible between the CVREF and CVREG capacitors. Keep high current traces as short and wide as possible to minimize parasitic series inductance, which causes spiking and electromagnetic interference (EMI). Avoid routing high impedance traces near any node connected to the SW1 and SW2 pins or near Inductors L1and L2 to prevent radiated switching noise injection. Place the feedback resistors as close to the FB1 and FB2 pins as possible to prevent high frequency switching noise injection. Place the top of the upper feedback resistors, RFT1 and RFT2, or route traces to them from as close as possible to the top of COUT1 and COUT2 for optimum output voltage sensing. Place the compensation components as close as possible to COMP1 and COMP2. Do not share vias to the ground plane with the feedback resistors to avoid coupling high frequency noise into the sensitive COMP1 and COMP2 pins. Place the CVREF and CVREG capacitors as close to the VREG and VREF pins as possible. Ensure that short traces are used between VREF and RFB2.

Figure 50. Suggested LFCSP Layout; Vias Connected to the PCB Ground Plane, Not to Scale

12068-051



20mm

Layout is important for all switching regulators but is particularly important for regulators with high switching frequencies. To achieve high efficiency, good regulation, good stability, and low noise, a well-designed PCB layout is required. Follow these guidelines when designing PCBs:

Figure 51. Suggested TSSOP Layout; Vias Connected to the PCB Ground Plane, Not to Scale

Rev. B | Page 26 of 27

Data Sheet

ADP5070

OUTLINE DIMENSIONS DETAIL A (JEDEC 95)

4.10 4.00 SQ 3.90

PIN 1 INDICATOR

0.30 0.25 0.18 16

0.50 BSC

PIN 1 INDIC ATOR AREA OPTIONS (SEE DETAIL A)

20 1

15

2.75 2.60 SQ 2.35

EXPOSED PAD 5

11

0.80 0.75 0.70

SIDE VIEW

PKG-005089

BOTTOM VIEW

0.05 MAX 0.02 NOM COPLANARITY 0.08 0.20 REF

SEATING PLANE

0.25 MIN

6

FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET. 02-21-2017-B

0.50 0.40 0.30

TOP VIEW

10

COMPLIANT TO JEDEC STANDARDS MO-220-WGGD-11.

Figure 52. 20-Lead Lead Frame Chip Scale Package [LFCSP] 4 mm × 4 mm Body and 0.75 mm Package Height (CP-20-8) Dimensions shown in millimeters 4.25 4.20 4.15

6.60 6.50 6.40

11

20

4.50 4.40 4.30

TOP VIEW 1

3.05 3.00 2.95

EXPOSED PAD (Pins Up)

6.40 BSC

10

BOTTOM VIEW

1.05 1.00 0.80

1.20 MAX

0.15 0.05

0.30 0.19

SEATING PLANE COPLANARITY 0.10

FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET.

8° 0° 0.20 0.09

0.75 0.60 0.45

COMPLIANT TO JEDEC STANDARDS MO-153-ACT

05-08-2006-A

0.65 BSC

Figure 53. 20-Lead Thin Shrink Small Outline With Exposed Pad [TSSOP_EP] (RE-20-1) Dimensions shown in millimeters

ORDERING GUIDE Model1 ADP5070ACPZ ADP5070ACPZ-R7 ADP5070AREZ ADP5070AREZ-R7 ADP5070CP-EVALZ ADP5070RE-EVALZ 1

Temperature Range −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C

Package Description 20-Lead Lead Frame Chip Scale Package [LFCSP] 20-Lead Lead Frame Chip Scale Package [LFCSP] 20-Lead Thin Shrink Small Outline With Exposed Pad [TSSOP_EP] 20-Lead Thin Shrink Small Outline With Exposed Pad [TSSOP_EP] Evaluation Board for the LFCSP Evaluation Board for the TSSOP_EP

Z = RoHS Compliant Part.

©2015–2017 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D12068-0-7/17(B)

Rev. B | Page 27 of 27

Package Option CP-20-8 CP-20-8 RE-20-1 RE-20-1