MCP1601, 500 mA Synchronous Buck Regulator The MCP1601, 500 mA synchronous buck regulator, is a fully integrated DC-to-DC switching converter that requires neither an external power transistor nor a power diode for operation within its rated current range. It is designed for down-converting standard battery and bus voltages to the operational voltages required in various systems. It has an adjustable output range of 0.9V to VIN and can be powered with an input voltage range of 2.7V to 5.5V. Given this input range, the MCP1601 is ideal for applications being powered with a single cell Li-Ion, or two or three cell NiMH, NiCd or alkaline batteries, as well as, from standard system bus voltages such as 5.0V, 3.3V or 3.0V. Some typical battery powered applications include: Cell Phones, PDAs, Digital Cameras, and USB powered devices. At the internally set PWM (Pulse Width Modulation) frequency of 750 kHZ, the MCP1601 can exceed 92% efficiency and deliver 500 mA of load current, while using low profile surface mount inductors and ceramic capacitors. Together these features minimize space, cost and wasted power. The MCP1601 has three operating modes; PWM for normal medium-to-high load conditions, PFM (Pulse Frequency Modulation) for light loads over extended periods of time, and LDO (Low Drop-Out) mode for when the input voltage approaches the output voltage and the PWM duty cycle approaches 100%. In the latter case, the buck switch transistor saturates and supplies the maximum possible voltage to the load. Switching between these modes is automatic and allows the MCP1601 to operate at maximum efficiency over a wide variation of line and load conditions. Typical Application (2.7V to 4.2V) VOUT Range 1.2V to 3.3V IOUT = 0 mA to 400 mA L Range 10 µH to 22 µH Input Voltage 2.7V - 4.2V CIN 10 µF VIN 1 SHDN 2 FB 3 8 MCP1601 AGND 4 LX 10 µH 7 PGND COUT 10 µF 6 VOUT COUT Range 10 µF to 47 µF 5 SYNC/PWM C1 47 pF R1 250k (for 1.8V) R2 200k Features: • Three Operating Modes: PWM, PFM and LDO (100% duty cycle) auto Switching between modes • All Ceramic Capacitor Solution • Integrated Buck and Synchronous Switches • Continuous Output Current Capability of 500 mA • Input Voltage Range of 2.7V to 5.5V • Low Voltage Output Capability of 0.9V • Fixed Switching Frequency of 750 kHz • Capable of PWM external synchronization up to 1.0 MHz • Over-temperature protection-on-chip • Integrated Under Voltage Lock-out • Integrated Soft-start Capability • Temperature Range of -40°C to +85°C • Available in a Small 8-pin MSOP Package Microchip Technology Inc.• The Embedded Control Solutions Company® Additional Information: • • • • • • • Microchip’s web site: www.microchip.com Microchip’s Technical Library CD-ROM, Order No. DS00161 Product Line Card, Order No. DS00148 Analog & Interface Families Data Book 2002, Order No. DS00207 2002 Technical Documentation Analog & Interface Product Families CD-ROM, Order No. DS51205 MCP1601 Data Sheet, DS21762 MCP1601 Evaluation Board User Guide, DS51315 Development Tools Support: The MCP1601 Evaluation Board is designed to demonstrate the use of the MCP1601 Synchronous Buck Regulator in a step-down, inductor-based DC-to-DC converter application. The MCP1601 Evaluation Board is constructed using one silk screen layer and two 1 oz. metal wiring layers. The bottom metal wiring layer is a single ground plane which is routed to partition the PGND high current return pin from the small signal AGND return pin on the MCP1601 device. MCP1601 500 mA Synchronous Buck Regulator Product MCP1601 Switching Frequency VCC Range PWM, PFM, LDO Operating Modes SHDN Current (Typical) Integrated Soft-start Under Voltage Lock-out Operating Temperature Range # of Pins/ Package 750 kHz 2.7V to 5.5V Yes 0.1 µA Yes Yes -40°C to +85°C 8MS Package Key: MS = MSOP Development Tools for Analog and Interface Products from Microchip MCP1601 Evaluation Board Demonstrates the Use of the MCP1601 Synchronous Buck Regulator FilterLab® Active Filter Software Design Tool MCP1252/1253 Evaluation Board Kit Support the MCP1252-33X50, MCP1252-ADJ, MCP1253-33X50 and MCP1253-ADJ Low Noise, Positive-regulated Charge Pump Devices MCP2120/2150 Developer’s Kit Infrared Products Developer’s Kit MCP2510 CAN Developer’s Kit MCP2510 CAN Evaluation/Development Tool MCP250XX CAN I/O Expanders Developer’s Kit MCP250XX CAN Evaluation/Development Tool MXDEV® 1 Analog Evaluation System: Evaluation Kit for MCP Devices MCP3001/02 Evaluation Board MCP3004/08 Evaluation Board MCP3201/02 Evaluation Daughter Kit MCP3204/08 Evaluation Daughter Kit MCP41XXX/MCP42XXX Evaluation Daughter Kit TC642 Demo Board Evaluation Kit for 10-bit Analog-to-Digital Converters Evaluation Kit for 10-bit Analog-to-Digital Converters Analog-to-Digital Converter - Four Channel* Analog-to-Digital Converter - Four Channel* Digital Potentiometers Evaluation and Demonstration* Fan Control Module for TC64X Devices TC642 Evaluation Kit Evaluation Kit for TC64X Fan Controllers TC650 Demo Board Demo Board for TC650/TC651 Fan Control ICs TC652 Demo Board Demo Board for TC652/TC653 Fan Control ICs TC74 Demo Board Demo Board for TC74 Digital Thermal Sensor *Note: Requires MXDEV® Analog Evaluation Kit. Visit our web site at www.microchip.com for additional product information and your local sales office. Microchip Technology Inc. • 2355 W. Chandler Blvd. • Chandler, AZ 85224-6199 • (480) 792-7200 • Fax (480) 792-9210 Information subject to change. The Microchip name and logo are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. The Embedded Control Solutions Company, FilterLab and MXDEV are registered trademarks of Microchip Technology Inc. in the U.S.A. All other trademarks mentioned herein are property of their respective owners. © 2003 Microchip Technology Inc. Printed in the U.S.A. All rights reserved. DS21763A 2/2003