Microchip Technology MCP1631RD-MCC2 Data Sheet

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MCP1631HV MULTI-CHEMISTRY
BATTERY CHARGER
REFERENCE DESIGN
© 2009 Microchip Technology Inc.
DS51791A-page 7
Chapter 2.  Installation and Operation
2.1
INTRODUCTION
The MCP1631HV Multi-Chemistry Battery Charger demonstrates Microchip’s 
high-speed Pulse Width Modulator (PWM), MCP1631HV, used in a multi-chemistry 
battery charger application. When used in conjunction with a microcontroller, the 
MCP1631HV will control the power system duty cycle to provide output voltage or 
current regulation. The PIC16F883 microcontroller can be used to regulate output 
voltage or set current, switching frequency and maximum duty cycle. The MCP1631HV 
generates the duty cycle and provides fast overcurrent protection based upon various 
external inputs. External signals include the switching frequency oscillator, the 
reference voltage, the feedback voltage and the current sense. The output signal is a 
square-wave pulse. The power train used for the MCP1631HV Multi-Chemistry Battery 
Charger is a Single-Ended Primary Inductive Converter (SEPIC). The MCP1631HV 
microcontroller is programmable, allowing the user to modify or develop their own 
firmware routines to further evaluate the MCP1631HV Multi-Chemistry Battery Charger 
in this application.
2.2
FEATURES
The MCP1631HV Multi-Chemistry Battery Charger has the following features:
• Input Operating Voltage Range - +5.3V to +16V
• Maximum of 2A Charge Current for single cell Li-Ion
• Charge NiMH, NiCd or Li-Ion Chemistries
• Charge 1 cell or 2 cell Li-Ion Batteries in Series
• Charge 1 cell to 5 cell NiMH or NiCd Batteries in Series
• Drive one or two 1 Watt LEDs in series.
• Select Chemistry and Cells using push-buttons
• ON/OFF switch
• Charge Status Indication
• Programmable Charge Profile
• Programmable Overvoltage Shutdown (1.8V/Cell for NiMH/NiCd or 4.4V/Cell for 
Li-Ion)
• Complete “C” source code is provided
2.3
GETTING STARTED
The MCP1631HV Multi-Chemistry Battery Charger is fully assembled and tested for 
charging one or two series Li-Ion Batteries, one to five series cell NiMH or NiCd 
batteries, or driving one to two 1 Watt LEDs. The charge termination for Li-Ion is based 
upon a percentage of fast charge current, the charge termination for NiMH is based on 
a negative voltage change versus time or positive temperature change versus time. 
This board requires the use of an external voltage source to charge the series 
connected batteries with a range of +5.3V to +16V input. An external load and 
thermistor is also required to evaluate the charger reference design.