MCP1612 Datasheet, PDF (1/22 Pages) Microchip Technology – Single 1A, 1.4 MHz Synchronous Buck Regulator

MCP1612
Single 1A, 1.4 MHz Synchronous Buck Regulator
Features
• Fixed Switching Frequency: 1.4 MHz
• Input Operating Voltage Range: 2.7V to 5.5V
• Integrated Buck and Synchronous Switches
• Adjustable-Output Voltage Range: 0.8V to 5.0V
• 100% Duty Cycle Capable for Low Input Voltage
• Continuous Output Current Capability: 1A
• Shutdown Control with I_Q < 0.01 µA (Typ.)
• Integrated Soft-Start Feature
• Integrated Undervoltage Lockout (UVLO)
Protection
• Integrated Overtemperature Protection
• Fast Dynamic Response to Line and Load Steps
• Small, 8-Pin DFN and MSOP Packages
• Operating Temperature Range: -40°C to +85°C
Applications
• Network Interface Cards
• Portable Computers
• Set-Top Boxes
• DSL Modems and Routers
• USB-Powered Devices
• GBIC Modules
• High-Speed Data System Bus Termination
• Medical Instruments
• Cellular/GSM/PHS Phones
• +5V or +3.3V Distributed Voltages
Description
The MCP1612 is a 1A, 1.4 MHz, fully-integrated,
current mode-controlled, synchronous buck regulator.
The MCP1612 is packaged in the 8-pin MSOP and
space-saving, 3x3 DFN packages. The DFN package
also provides a lower thermal resistance package
option for high-power, high ambient temperature
applications. With an input operating range from 2.7V
to 5.5V, the MCP1612 is ideal for applications that are
powered by one single-cell Li-Ion, 2- to 3-cell NiMH,
NiCd or alkaline sources.
The output voltage of the MCP1612 is easily set over
the range of 0.8V to 5.0V by using an external resistor
divider. The external inductor and output capacitor size
are minimized due to an internally-fixed, 1.4 MHz clock
being used to set the switching frequency. The fixed
clock allows for continuous, fixed-frequency PWM
operation over the full load range.
The MCP1612 is designed to provide fast dynamic
response to sudden changes in input voltage and load
current to minimize the necessary amount of external
output capacitance.
The MCP1612 can be used with ceramic, tantalum or
aluminum electrolytic output capacitors. Ceramic
capacitors with values as low as 4.7 µF can be used to
keep the output ripple voltage low. For applications that
require better load step performance, the value of the
output capacitor can be increased to 47 µF.
Additional features integrated into the MCP1612
include shutdown capability, soft-start, UVLO,
overcurrent and overtemperature protection.
Package Types
8-Lead DFN
8-Lead MSOP
V_{IN 1}
V_CC 2
SHDN 3
COMP 4
8 L_X
7 P_GND
6 _AGND
5 FB
V_{IN 1}
V_CC 2
SHDN 3
COMP 4
8 L_X
7 P_GND
6 _AGND
5 FB
© 2005 Microchip Technology Inc.
DS21921B-page 1