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MCP1632 SINGLE CELL
LI-ION BATTERY CHARGER
DEMO BOARD USER’S GUIDE
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2014 Microchip Technology Inc. DS50002321A-page 9
Chapter 1. Product Overview
1.1 INTRODUCTION
The MCP1632 Single-Cell Li-Ion Battery Charger Demo Board is a step-up/step-down,
switch-mode, DC/DC converter used for battery charging applications. The demo
board provides a 4.2V constant voltage source. Other output voltages can be obtained
with minor modifications to the board’s Bill of Materials (BOM).
The MCP1632 Single-Cell Li-Ion Battery Charger Demo Board is an intelligent battery
charging system for a single-cell Lithium-Ion battery. MCP1632 Single-Cell Li-Ion Bat-
tery Charger Demo Board utilizes Microchip's MCP1632 high-speed Pulse-Width Mod-
ulator (PWM). The 8-pin MCP1632 device contains all the analog components
necessary for a peak current mode control loop including an error amplifier, PWM
comparator and a high-current driver output pin.
An 8-pin PIC12F1822 microcontroller is used to implement the charging algorithm. In
addition, the PIC12F1822 firmware supervises the battery voltage and current.
1.2 BOARD FEATURES
The MCP1632 Single-Cell Li-Ion Battery Charger Demo Board has the following
features:
• Compact size, highly efficient battery charger
• Can operate in Buck (step-down) or Boost (step-up) mode
• Maximum output current: 1500 mA; can be adjusted via firmware
• Chemistry-optimized charging algorithm
• Maximum output power: 7W
• Factory-programmed source code provided
• Additional application functions can be implemented in the firmware
1.3 DEVICE SUMMARY
The MCP1632 Single-Cell Li-Ion Battery Charger Demo Board uses the following
primary devices on the board:
• MCP1632 high-speed current mode PWM controller. – When used in conjunction
with a microcontroller, the MCP1632 will control the power system duty cycle to
provide output current and/or voltage regulation.
• PIC12F1822 microcontroller (8-bit MCU) – Used to implement the charging algo-
rithm and to provide additional software functions like protections.
• MCP1703 low dropout regulator (LDO) – Used to supply regulated voltage (+5V)
to the PIC12F1822 microcontroller and the MCP1632 PWM controller
• MCP6021 operational amplifier – Used for the current sensing circuit.