ADP2303ARDZ-R7

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2 A/3 A, 20 V, 700 kHz, Nonsynchronous Step-Down Regulators Data Sheet ADP2302/ADP2303 Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2010–2012 Analog Devices, Inc. All rights reserved. FEATURES Wide input voltage range: 3.0 V to 20 V Maximum load current 2 A for ADP2302 3 A for ADP2303 ±1.5% output accuracy over temperature Output voltage down to 0.8 V 700 kHz switching frequency Current-mode control architecture Automatic PFM/PWM mode Precision enable pin with hysteresis Integrated high-side MOSFET Integrated bootstrap diode Internal compensation and soft start Power-good output Undervoltage lockout (UVLO) Overcurrent protection (OCP) Thermal shutdown (TSD) 8-lead SOIC package with exposed paddle Supported by ADIsimPower™ design tool APPLICATIONS Intermediate power rail conversion DC-to-DC point of load applications Communications and networking Industrial and instrumentation Healthcare and medical Consumer TYPICAL APPLICATIONS CIRCUIT VIN VIN VOUT ADP2302/ ADP2303 PGOOD EN GND OFF ON BST SW FB 08 83 3- 00 1 Figure 1. Typical Application Circuit 40 50 60 70 80 90 100 0 0.5 1.0 1.5 2.0 2.5 3.0 EF FI C IE N C Y (% ) OUTPUT CURRENT (A) INDUCTOR: VLF10040T-4R7N5R4 DIODE: SSB43L VOUT = 3.3V VOUT = 5.0V 08 83 3- 00 2 Figure 2. ADP2303 Efficiency vs. Output Current at VIN = 12 V GENERAL DESCRIPTION The ADP2302/ADP2303 are fixed frequency, current-mode control, step-down, dc-to-dc regulators with an integrated power MOSFET. The ADP2302/ADP2303 can run from an input voltage of 3.0 V to 20 V, which makes them suitable for a wide range of applications. The output voltage of the ADP2302/ ADP2303 can be down to 0.8 V for the adjustable version, while the fixed output version is available in preset output voltage options of 5.0 V, 3.3 V, and 2.5 V. The 700 kHz operating frequency allows small inductor and ceramic capacitors to be used, providing a compact solution. Current mode control provides fast and stable line and load transient performance. The ADP2302/ADP2303 have integrated soft start circuitry to prevent a large inrush current at power-up. The power-good signal can be used to sequence devices that have an enable input. The precision enable threshold voltage allows the part to be easily sequenced from other input/output supplies. Other key features include undervoltage lockout (UVLO), overvoltage protection (OVP), thermal shutdown (TSD), and overcurrent protection (OCP). The ADP2302/ADP2303 devices are available in the 8-lead, SOIC package with exposed paddle and are rated for the −40oC to +125oC junction temperature range.

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ADP2302/ADP2303 Data Sheet Rev. A | Page 2 of 28 TABLE OF CONTENTS Features .............................................................................................. 1  Applications ....................................................................................... 1  Typical Applications Circuit ............................................................ 1  General Description ......................................................................... 1  Revision History ............................................................................... 2  Specifications ..................................................................................... 3  Absolute Maximum Ratings ............................................................ 4  Thermal Resistance ...................................................................... 4  ESD Caution .................................................................................. 4  Pin Configuration and Function Descriptions ............................. 5  Typical Performance Characteristics ............................................. 6  Functional Block Diagram ............................................................ 13  Theory of Operation ...................................................................... 14  Basic Operation .......................................................................... 14  PWM Mode ................................................................................. 14  Power Saving Mode .................................................................... 14  Bootstrap Circuitry .................................................................... 14  Precision Enable ......................................................................... 14  Integrated Soft Start ................................................................... 14  Current Limit .............................................................................. 14  Short-Circuit Protection ............................................................ 14  Undervoltage Lockout (UVLO) ............................................... 15  Thermal Shutdown (TSD) ......................................................... 15  Overvoltage Protection (OVP) ................................................. 15  Power Good ................................................................................ 15  Control Loop ............................................................................... 15  Applications Information .............................................................. 16  ADIsimPower Design Tool ....................................................... 16  Programming Output Voltage .................................................. 16  Voltage Conversion Limitations ............................................... 16  Low Input Voltage Considerations .......................................... 17  Programming the Precision Enable ......................................... 17  Inductor ....................................................................................... 17  Catch Diode ................................................................................ 18  Input Capacitor ........................................................................... 19  Output Capacitor........................................................................ 19  Thermal Consideration ............................................................. 19  Design Example .............................................................................. 20  Catch Diode Selection ............................................................... 20  Inductor Selection ...................................................................... 20  Output Capacitor Selection....................................................... 20  Resistive Voltage Divider Selection .......................................... 20  Circuit Board Layout Recommendations ................................... 22  Typical Application Circuits ......................................................... 23  Outline Dimensions ....................................................................... 26  Ordering Guide .......................................................................... 26  REVISION HISTORY 6/12—Rev. 0 to Rev. A Change to Features Section ............................................................. 1 Added ADIsimPower Design Tool Section ................................. 16 Change to Voltage Conversion Limitations Section .................. 16 Updated Outline Dimensions ....................................................... 26 Changes to Ordering Guide .......................................................... 26 7/10—Revision 0: Initial Version

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Data Sheet ADP2302/ADP2303 Rev. A | Page 3 of 28 SPECIFICATIONS VIN = 3.3 V, TJ = −40°C to +125°C for minimum/maximum specifications, and TA = 25°C for typical specifications, unless otherwise noted. Table 1. Parameters Symbol Test Conditions Min Typ Max Unit VIN Voltage Range VIN 3.0 20 V Supply Current IVIN No switching, VIN = 12 V 720 950 μA Shutdown Current ISHDN VEN = 0 V, VIN = 12 V 24 45 μA Undervoltage Lockout Threshold UVLO VIN rising 2.7 2.9 V VIN falling 2.2 2.4 V FB Regulation Voltage VFB ADP230xARDZ (adjustable) 0.788 0.8 0.812 V ADP230xARDZ-2.5 2.463 2.5 2.538 V ADP230xARDZ-3.3 3.25 3.3 3.35 V ADP230xARDZ-5.0 4.925 5.0 5.075 V Bias Current IFB ADP230xARDZ (adjustable) 0.01 0.1 μA SW On Resistance1 VBST − VSW = 5 V, ISW = 200 mA 80 120 160 mΩ Peak Current Limit ADP2302, VBST − VSW = 5 V 2.7 3.5 4.4 A ADP2303, VBST − VSW = 5 V 4.6 5.5 6.4 A Leakage Current VEN = VSW = 0 V, VIN = 12 V 0.1 5 μA Minimum On Time 126 170 ns Minimum Off Time 210 280 ns OSCILLATOR FREQUENCY fSW 595 700 805 kHz SOFT START TIME 2048 Clock cycles EN Input Threshold VEN 1.12 1.2 1.28 V Input Hysteresis 100 mV Pull-Down Current 1.2 μA BOOTSTRAP VOLTAGE VBOOT VIN = 12 V 4.7 5.0 5.3 V PGOOD PGOOD Rising Threshold 82.5 87.5 92.5 % PGOOD Hysteresis 2.5 % PGOOD Deglitch Time2 32 Clock cycles PGOOD Output Low Voltage 150 300 mV PGOOD Leakage Current VPGOOD = 5 V 0.1 1 μA THERMAL SHUTDOWN Threshold Rising temperature 150 °C Hysteresis 15 °C 1 Pin-to-Pin measurements. 2 Guaranteed by design.

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ADP2302/ADP2303 Data Sheet Rev. A | Page 4 of 28 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter MAX Rating VIN, EN, PGOOD −0.3 V to +24 V SW −1.0 V to +24 V BST to SW −0.6 V to +6 V FB, NC −0.3 V to +6 V Operating Junction Temperature Range −40°C to +125°C Storage Temperature Range −65°C to +150°C Soldering Conditions JEDEC J-STD-020 Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Absolute maximum ratings apply individually only, not in combination. Unless otherwise specified, all voltages are referenced to GND. THERMAL RESISTANCE θJA is specified for the worst-case conditions, that is, a device soldered in a circuit board for surface-mount packages. Table 3. Thermal Resistance1 Package Type θJA Unit 8-Lead SOIC_N_EP 58.5 °C/W 1 JA is measured using natural convection on JEDEC 4-layer board. ESD CAUTION

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Data Sheet ADP2302/ADP2303 Rev. A | Page 5 of 28 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS BST 1 VIN 2 EN 3 PGOOD 4 SW8 GND7 NC6 FB5 NOTES 1. NC = NO CONNECT. 2. THE EXPOSED PAD SHOULD BE SOLDERED TO AN EXTERNAL GROUND PLANE UNDERNEATH THE IC FOR THERMAL DISSIPATION. ADP2302 ADP2303 TOP VIEW (Not to Scale) 08 83 3- 00 3 Figure 3. Pin Configuration (Top View) Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 BST Bootstrap Supply for the High-Side MOSFET Driver. A 0.1 μF capacitor is connected between SW and BST to provide a floating driver voltage for the power switch. 2 VIN Power Input. Connect to the input power source with a ceramic bypass capacitor to GND directly from this pin. 3 EN Output Enable. Pull this pin high to enable the output. Pull this pin low to disable the output. This pin can also be used as a programmable UVLO input. This pin has an internal 1.2 μA pull-down current to GND. 4 PGOOD Power-Good Open-Drain Output. 5 FB Feedback Voltage Sense Input. For the adjustable version, connect this pin to a resistive divider from VOUT. For the fixed output version, connect this pin to VOUT directly. 6 NC Used for internal testing. Connect to GND or leave this pin floating to ensure proper operation. 7 GND Ground. Connect this pin to the ground plane. 8 SW Switch Node Output. Connect an inductor to VOUT and a catch diode to GND from this pin. 9 (EPAD) Exposed Pad The exposed pad should be soldered to an external ground plane underneath the IC for thermal dissipation.

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ADP2302/ADP2303 Data Sheet Rev. A | Page 6 of 28 TYPICAL PERFORMANCE CHARACTERISTICS VIN = 3.3 V, TA = 25°C, unless otherwise noted. 40 50 60 70 80 90 100 0 0.5 1.0 1.5 2.0 2.5 3.0 E F F IC IE N C Y ( % ) OUTPUT CURRENT (A) VOUT = 2.5V VOUT = 3.3V VOUT = 5.0V INDUCTOR: VLF10040T-6R8N4R5 DIODE: SSB43L 08 83 3- 00 4 Figure 4. ADP2303 Efficiency, VIN = 18 V 40 50 60 70 80 90 100 0 0.5 1.0 1.5 2.0 2.5 3.0 E F F IC IE N C Y ( % ) OUTPUT CURRENT (A) VOUT = 1.8V VOUT = 1.5V VOUT = 1.2V VOUT = 2.5V INDUCTOR: VLF10040T-2R2N7R1 DIODE: SSB43L 08 83 3- 00 5 Figure 5. ADP2303 Efficiency, VIN = 5 V 40 50 60 70 80 90 100 0 0.5 1.0 1.5 2.0 E F F IC IE N C Y ( % ) OUTPUT CURRENT (A) INDUCTOR: VLF10040T-6R8N4R5 DIODE: SSB43L VOUT = 2.5V VOUT = 1.8V VOUT = 1.5V VOUT = 3.3V VOUT = 5.0V 08 83 3- 00 6 Figure 6. ADP2302 Efficiency, VIN = 12 V 0 0.5 1.0 1.5 2.0 2.5 3.0 40 50 60 70 80 90 100 E F F IC IE N C Y ( % ) OUTPUT CURRENT (A) INDUCTOR: VLF10040T-4R7N5R4 DIODE: SSB43L 08 83 3- 00 7 VOUT = 2.5V VOUT = 1.8V VOUT = 1.5V VOUT = 3.3V VOUT = 5.0V Figure 7. ADP2303 Efficiency, VIN = 12 V 40 50 60 70 80 90 100 0 0.5 1.0 1.5 2.0 E F F IC IE N C Y ( % ) OUTPUT CURRENT (A) VOUT = 2.5V VOUT = 3.3V VOUT = 5.0V INDUCTOR: VLF10040T-6R8N4R5 DIODE: SSB43L 08 83 3- 00 8 Figure 8. ADP2302 Efficiency, VIN = 18 V 40 50 60 70 80 90 100 0 0.5 1.0 1.5 2.0 E F F IC IE N C Y ( % ) OUTPUT CURRENT (A) INDUCTOR: VLF10040T-3R3N6R2 DIODE: SSB43L VOUT = 1.8V VOUT = 1.5V VOUT = 1.2V VOUT = 2.5V 08 83 3- 00 9 Figure 9. ADP2302 Efficiency, VIN = 5 V

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Data Sheet ADP2302/ADP2303 Rev. A | Page 7 of 28 –0.20 –0.15 –0.10 –0.05 0 0.05 0.10 0.15 0.20 5 8 11 14 17 20 L IN E R E G U L A T IO N ( % ) VIN (V) 08 83 3- 01 0 Figure 10. ADP2302 Line Regulation, VOUT = 3.3 V, IOUT = 2 A –0.20 –0.15 –0.10 –0.05 0 0.05 0.10 0.15 0.20 5 8 11 14 17 20 L IN E R E G U L A T IO N ( % ) VIN (V) 08 83 3- 01 1 Figure 11. ADP2303 Line Regulation, VOUT = 3.3 V , IOUT = 3 A 0 5 10 15 20 25 30 35 40 45 50 2 4 6 8 10 12 14 16 18 20 S H U T D O W N C U R R E N T ( μ A ) VIN (V) TJ = –40°C TJ = +25°C TJ = +125°C 08 83 3- 01 2 Figure 12. Shutdown Current vs. VIN –0.20 –0.15 –0.10 –0.05 0 0.05 0.10 0.15 0.20 0 0.5 1.0 1.5 2.0 L O A D R E G U L A T IO N ( % ) OUTPUT CURRENT (A) 08 83 3- 01 3 Figure 13. ADP2302 Load Regulation, VOUT = 3.3V, VIN = 12 V –0.20 –0.15 –0.10 –0.05 0 0.05 0.10 0.15 0.20 0 0.5 1.0 1.5 2.0 2.5 3.0 L O A D R E G U L A T IO N ( % ) OUTPUT CURRENT (A) 08 83 3- 01 4 Figure 14. ADP2303 Load Regulation, VOUT = 3.3 V, VIN = 12 V 500 550 600 650 700 750 800 850 900 2 4 6 8 10 12 14 16 18 20 Q U IE S C E N T C U R R E N T ( μ A ) VIN (V) TJ = –40°C TJ = +25°C TJ = +125°C 08 83 3- 01 5 Figure 15. Quiescent Current vs. VIN

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ADP2302/ADP2303 Data Sheet Rev. A | Page 8 of 28 590 610 630 650 670 690 710 730 750 770 790 810 –40 –20 0 20 40 60 80 100 120 F R E Q U E N C Y ( kH z) TEMPERATURE (°C) 08 83 3- 01 6 Figure 16. Frequency vs. Temperature 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.0 4.2 4.4 –40 –20 0 20 40 60 80 100 120 P E A K C U R R E N T L IM IT ( A ) TEMPERATURE (°C) 08 83 3- 01 7 Figure 17. ADP2302 Current-Limit Threshold vs. Temperature, VBST − VSW = 5 V 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 U V L O T H R E S H O L D ( V ) TEMPERATURE (°C) –40 –20 0 20 40 60 80 100 120 RISING FALLING 08 83 3- 01 8 Figure 18. UVLO Threshold vs. Temperature 788 790 792 794 796 798 800 802 804 806 808 810 812 F E E D B A C K V O LT A G E ( m V ) TEMPERATURE (°C) –40 –20 0 20 40 60 80 100 120 08 83 3- 01 9 Figure 19. 0.8 V Feedback Voltage vs. Temperature 4.6 4.8 5.0 5.2 5.4 5.6 5.8 6.0 6.2 6.4 P E A K C U R R E N T L IM IT ( A ) –40 –20 0 20 40 60 80 100 120 TEMPERATURE (°C) 08 83 3- 02 0 Figure 20. ADP2303 Current-Limit Threshold vs. Temperature, VBST − VSW = 5 V 1.05 1.00 1.10 1.15 1.20 1.25 1.30 E N A B L E T H R E S H O L D ( V ) TEMPERATURE (°C) –40 –20 0 20 40 60 80 100 120 RISING FALLING 08 83 3- 02 1 Figure 21. Enable Threshold vs. Temperature

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Data Sheet ADP2302/ADP2303 Rev. A | Page 9 of 28 205 210 215 220 225 230 235 240 245 250 255 260 265 270 M IN IM U M O F F T IM E ( n s) TEMPERATURE (°C) –40 –20 0 20 40 60 80 100 120 08 83 3- 02 2 Figure 22. Minimum Off Time vs. Temperature 60 70 80 90 100 110 120 130 140 150 160 170 180 M O S F E T R E S IS T O R ( m Ω ) VGS = 3V VGS = 4V VGS = 5V TEMPERATURE (°C) –40 –20 0 20 40 60 80 100 120 08 83 3- 02 3 Figure 23. MOSFET RDSON vs. Temperature (Pin-to-Pin Measurement) CH1 5.00mV BW CH2 5.00V M1.00µs A CH2 7.50V 1 4 2 T 30.00% VOUT (AC) IL SW CH4 2.00A Ω 08 83 3- 02 4 Figure 24. Discontinuous Conduction Mode (DCM), VOUT = 3.3 V, VIN = 12 V 100 105 110 115 120 125 130 135 140 145 150 M IN IM U M O N T IM E ( n s) TEMPERATURE (°C) –40 –20 0 20 40 60 80 100 120 08 83 3- 02 5 Figure 25. Minimum On Time vs. Temperature CH1 5.00mV BW CH2 5.00V CH4 2.00A Ω M1.00µs A CH2 7.50V 1 4 2 T 30.00% VOUT (AC) IL SW 08 83 3- 02 6 Figure 26. Continuous Conduction Mode (CCM), VOUT = 3.3 V, VIN = 12 V CH1 50.00mV BW CH2 5.00V CH4 2.00A Ω M200µs A CH2 7.50V 1 4 2 T 30.00% VOUT (AC) IL SW 08 83 3- 02 7 Figure 27. Power Saving Mode, VOUT = 3.3 V, VIN = 12 V