Microchip MCP1642B

Description

The MCP1642B/D devices are compact, high-efficiency, fixed-frequency, synchronous step-up DC-DC converters. This family of devices provides aneasy-to-use power supply solution for applications powered by either one-cell, two-cell, or three-cell alkaline, Ultimate Lithium, NiCd, NiMH, one-cell Li-Ion or Li-Polymer batteries.

Low-voltage technology allows the regulator to start-up without high inrush current or output voltage overshoot from a low voltage input. High efficiency is accomplished by integrating the low-resistance N-Channel Boost switch and synchronous P-Channel switch. All compensation and protection circuitry are integrated to minimize the number of externalcomponents. An open-drain Power Good output is provided to indicate when the output voltage is within 10% of regulation and facilitates the interface with an MCU. For standby applications, MCP1642B provides a “true output disconnect” from input to output while in shutdown (EN = GND). An additional device option (MCP1642D) is available and connects “input to output bypass” while in shutdown. Both options consume lessthan 1 μA of input current.

For the adjustable (ADJ) device options, the output voltage is set by a small external resistor divider. Fixed VOUT device options do not require external divider resistors. Two package options, 8-lead MSOP and 8- lead 2x3 DFN, are available.

Features

• Up to 96% Typical Efficiency
• 1.8A Typical Peak Input Current Limit:
• IOUT > 175 mA @ 1.2V VIN, 3.3V VOUT
• IOUT > 600 mA @ 2.4V VIN, 3.3V VOUT
• IOUT > 800 mA @ 3.3V VIN, 5.0V VOUT
• IOUT > 1A @ VIN > 3.6V, 5.0V VOUT
• Low Start-Up Voltage: 0.65V, typical 3.3V VOUT @ 1 mA
• Low Operating Input Voltage: 0.35V, typical 3.3V VOUT @ 1 mA
• Output Voltage Range:
• Reference Voltage, VFB = 1.21V
• 1.8V to 5.5V for the adjustable device option
• 1.8V, 3.0V, 3.3V and 5.0V for fixed VOUT options
• Maximum Input Voltage  VOUT < 5.5V
• PWM Operation: 1 MHz Low Noise, Anti-Ringing Control
• Power Good Open-Drain Output
• Internal Synchronous Rectifier
• Internal Compensation
• Inrush Current Limiting and Internal Soft-Start
• Selectable, Logic-Controlled Shutdown States:
• True Load Disconnect Option (MCP1642B)
• Input-to-Output Bypass Option (MCP1642D)
• Shutdown Current (All States): 1 μA
• Overtemperature Protection
• Available Packages:
• 8-Lead MSOP
• 8-Lead 2x3 DFN

Remarks:

• 5V output voltage with 700mA current is added from MCP1642B/DTwo-Cell to USB Power Evaluation Board User’s Guide

Typical applications

• Personal Medical Products
• Single-Cell Li-Ion to 5V Converters
• Wireless Sensors
• Hand-Held Instruments
• +3.3V to +5.0V Distributed Power Supply
• USB Emergency Backup Charger from Batteries
• PIC® MCU Power
• One, Two and Three-Cell Alkaline, Lithium
• GPS Receivers

More information

• Datasheet
• IC product information