Microchip Technology MCP1631 Evaluation Board MCP1631RD-DCPC1 MCP1631RD-DCPC1 Data Sheet

Product codes
MCP1631RD-DCPC1
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MCP1631HV DIGITALLY CONTROLLED
PROGRAMMABLE CURRENT SOURCE
REFERENCE DESIGN
© 2009 Microchip Technology Inc.
DS51798A-page 7
Chapter 2.  Installation and Operation
2.1
INTRODUCTION
The MCP1631HV Digitally Controlled Programmable Current Source Reference 
Design demonstrates Microchip’s MCP1631HV high-speed Pulse Width Modulator 
(PWM) used in LED lighting and multi-chemistry battery charger applications. When 
used in conjunction with a microcontroller, the MCP1631HV will control the power 
system duty cycle to provide output voltage or current regulation. A PIC16F616 
microcontroller is used to provide the MCP1631HV switching frequency oscillator and 
reference voltage. The MCP1631HV generates a duty cycle and provides fast 
overcurrent protection based upon the feedback and current sense inputs. 
MCP1631HV external signals include the input oscillator, the reference voltage, the 
feedback voltage and the current sense. The  MCP1631HV generates a square-wave 
output signal to drive the powertrain switch. The power train used for the MCP1631HV 
Digitally Controlled Programmable Current Source Reference Design is a 
Single-Ended Primary Inductive Converter (SEPIC). The PIC16F616 microcontroller is 
programmable, allowing the user to modify or develop their own firmware routines to 
further evaluate the MCP1631HV Digitally Controlled Programmable Current Source 
Reference Design in this application.
2.2
FEATURES
The MCP1631HV Digitally Controlled Programmable Current Source Reference 
Design has the following features:
• Input Operating Voltage Range: +3.5V to +16V
• Firmware default output current of 700 mA with dimming ratio 10:1 (70 mA/step)
• Maximum output current of 1000 mA
• Maximum output power of 8.5W
• Drive one or more LEDs
• Firmware for charging Li-Ion, NiMH, and NiCd batteries
• ON/OFF/Dimming switch
• Status and fault indication
• Hardware and software overvoltage protection (OVP) set to 9.0V. The software 
value can be modified in the source code to be less than 9.0V