Datasheet ADP2140 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 3 MHz, 600 mA, Low Quiescent Current Buck with 300 mA LDO Regulator |
| Pages / Page | 32 / 1 — 3 MHz, 600 mA, Low Quiescent Current. Buck with 300 mA LDO Regulator. … |
| Revision | A |
| File Format / Size | PDF / 2.8 Mb |
| Document Language | English |
3 MHz, 600 mA, Low Quiescent Current. Buck with 300 mA LDO Regulator. Data Sheet. ADP2140. FEATURES. TYPICAL APPLICATION CIRCUITS
Model Line for this Datasheet
Text Version of Document
3 MHz, 600 mA, Low Quiescent Current Buck with 300 mA LDO Regulator Data Sheet ADP2140 FEATURES TYPICAL APPLICATION CIRCUITS Input voltage range: 2.3 V to 5.5 V VIN1 = 3.6V LDO input (VIN2) 1.65 V to 5.5 V C + IN 10µF ADP2140 Buck output voltage range: 1.0 V to 3.3 V 100kΩ 10 VIN1 PGND 1 1µH V LDO output voltage range: 0.8 V to 3.3 V OUT = 1.2V PG 9 PG SW 2 Buck output current: 600 mA EN1 8 EN1 AGND 3 + COUT 10µF LDO output current: 300 mA EN2 7 EN2 FB 4 VOUT2 = 1.8V LDO quiescent current: 22 μA with zero load 6 VOUT2 VIN2 5 C + OUT2
1
Buck quiescent current: 20 μA in PSM mode 1µF
00 2- 93
Low shutdown current: <0.3 μA
07 Figure 1. ADP2140 with LDO Connected to V
Low LDO dropout 110 mV @ 300 mA load
IN1
High LDO PSRR VIN1 = 3.3V 65 dB @ 10 kHz at V C + OUT2 = 1.2 V IN 10µF ADP2140 55 dB @ 100 kHz at V 100kΩ OUT2 = 1.2 V 10 VIN1 PGND 1 1µH V Low noise LDO: 40 μV rms at V OUT = 1.8V OUT2 = 1.2 V PG 9 PG SW 2 Initial accuracy: ±1% EN1 8 EN1 AGND 3 + COUT 10µF Current-limit and thermal overload protection EN2 7 EN2 FB 4 VOUT2 = 1.2V Power-good indicator 6 VOUT2 VIN2 5 C +
2
Optional enable sequencing OUT2 1µF
-00 932
10-lead 0.75 mm × 3 mm × 3 mm LFCSP package
07 Figure 2. ADP2140 with LDO Connected to Buck Output
APPLICATIONS Mobile phones Personal media players Digital camera and audio devices Portable and battery-powered equipment GENERAL DESCRIPTION
cell, multiple alkaline/NiMH cell, PCMCIA, and other standard The ADP2140 includes a high efficiency, low quiescent 600 mA power sources. stepdown dc-to-dc converter and a 300 mA LDO packaged in a ADP2140 includes a power-good pin, soft start, and internal small 10-lead 3 mm × 3 mm LFCSP. The total solution requires compensation. Numerous power sequencing options are user- only four tiny external components. selectable through two enable inputs. In autosequencing mode, The buck regulator uses a proprietary high speed current-mode, the highest voltage output enables on the rising edge of EN1. constant frequency, pulse-width modulation (PWM) control During logic controlled shutdown, the input disconnects from scheme for excellent stability and transient response. To ensure the output and draws less than 300 nA from the input source. the longest battery life in portable applications, the ADP2140 has Other key features include: undervoltage lockout to prevent deep a power saving variable frequency mode to reduce switching fre- battery discharge, soft start to prevent input current overshoot quency under light loads. at startup, and both short-circuit protection and thermal overload The LDO is a low quiescent current, low dropout linear regulator protection circuits to prevent damage in adverse conditions. designed to operate in a split supply mode with VIN2 as low as When the ADP2140 is used with two 0603 capacitors, one 0402 1.65 V. The low input voltage minimum allows the LDO to be capacitor, one 0402 resistor, and one 0805 chip inductor, the total powered from the output of the buck regulator increasing effi- solution size is approximately 90 mm2 resulting in the smallest foot- ciency and reducing power dissipation. The ADP2140 runs from print solution to meet a variety of portable applications. input voltages of 2.3 V to 5.5 V allowing single Li+/Li− polymer
Rev. A Document Feedback 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 ©2010–2012 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com
Document Outline Features Applications General Description Typical Application Circuits Revision History Specifications Recommended Specifications: Capacitors and Inductor Pin Configuration and Function Descriptions Typical Performance Characteristics Buck Output LDO Output Theory of Operation Buck Section Control Scheme PWM Operation PSM Operation Pulse Skipping Threshold Selected Features Short-Circuit Protection Undervoltage Lockout Thermal Protection Soft Start Current Limit Power-Good Pin LDO Section Applications Information Power Sequencing Power-Good Function External Component Selection Selecting the Inductor Output Capacitor Input Capacitor Efficiency Power Switch Conduction Losses Inductor Losses Switching Losses Transition Losses Recommended Buck External Components LDO Capacitor Selection Output Capacitor Input Bypass Capacitor Input and Output Capacitor Properties LDO as a Postregulator to Reduce Buck Output Noise Thermal Considerations PCB Layout Considerations Outline Dimensions Ordering Guide
1
Buck quiescent current: 20 μA in PSM mode 1µF
00 2- 93
Low shutdown current: <0.3 μA
07 Figure 1. ADP2140 with LDO Connected to V
Low LDO dropout 110 mV @ 300 mA load
IN1
High LDO PSRR VIN1 = 3.3V 65 dB @ 10 kHz at V C + OUT2 = 1.2 V IN 10µF ADP2140 55 dB @ 100 kHz at V 100kΩ OUT2 = 1.2 V 10 VIN1 PGND 1 1µH V Low noise LDO: 40 μV rms at V OUT = 1.8V OUT2 = 1.2 V PG 9 PG SW 2 Initial accuracy: ±1% EN1 8 EN1 AGND 3 + COUT 10µF Current-limit and thermal overload protection EN2 7 EN2 FB 4 VOUT2 = 1.2V Power-good indicator 6 VOUT2 VIN2 5 C +
2
Optional enable sequencing OUT2 1µF
-00 932
10-lead 0.75 mm × 3 mm × 3 mm LFCSP package
07 Figure 2. ADP2140 with LDO Connected to Buck Output
APPLICATIONS Mobile phones Personal media players Digital camera and audio devices Portable and battery-powered equipment GENERAL DESCRIPTION
cell, multiple alkaline/NiMH cell, PCMCIA, and other standard The ADP2140 includes a high efficiency, low quiescent 600 mA power sources. stepdown dc-to-dc converter and a 300 mA LDO packaged in a ADP2140 includes a power-good pin, soft start, and internal small 10-lead 3 mm × 3 mm LFCSP. The total solution requires compensation. Numerous power sequencing options are user- only four tiny external components. selectable through two enable inputs. In autosequencing mode, The buck regulator uses a proprietary high speed current-mode, the highest voltage output enables on the rising edge of EN1. constant frequency, pulse-width modulation (PWM) control During logic controlled shutdown, the input disconnects from scheme for excellent stability and transient response. To ensure the output and draws less than 300 nA from the input source. the longest battery life in portable applications, the ADP2140 has Other key features include: undervoltage lockout to prevent deep a power saving variable frequency mode to reduce switching fre- battery discharge, soft start to prevent input current overshoot quency under light loads. at startup, and both short-circuit protection and thermal overload The LDO is a low quiescent current, low dropout linear regulator protection circuits to prevent damage in adverse conditions. designed to operate in a split supply mode with VIN2 as low as When the ADP2140 is used with two 0603 capacitors, one 0402 1.65 V. The low input voltage minimum allows the LDO to be capacitor, one 0402 resistor, and one 0805 chip inductor, the total powered from the output of the buck regulator increasing effi- solution size is approximately 90 mm2 resulting in the smallest foot- ciency and reducing power dissipation. The ADP2140 runs from print solution to meet a variety of portable applications. input voltages of 2.3 V to 5.5 V allowing single Li+/Li− polymer
Rev. A Document Feedback 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 ©2010–2012 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com
Document Outline Features Applications General Description Typical Application Circuits Revision History Specifications Recommended Specifications: Capacitors and Inductor Pin Configuration and Function Descriptions Typical Performance Characteristics Buck Output LDO Output Theory of Operation Buck Section Control Scheme PWM Operation PSM Operation Pulse Skipping Threshold Selected Features Short-Circuit Protection Undervoltage Lockout Thermal Protection Soft Start Current Limit Power-Good Pin LDO Section Applications Information Power Sequencing Power-Good Function External Component Selection Selecting the Inductor Output Capacitor Input Capacitor Efficiency Power Switch Conduction Losses Inductor Losses Switching Losses Transition Losses Recommended Buck External Components LDO Capacitor Selection Output Capacitor Input Bypass Capacitor Input and Output Capacitor Properties LDO as a Postregulator to Reduce Buck Output Noise Thermal Considerations PCB Layout Considerations Outline Dimensions Ordering Guide
