Microchip Technology MCP1630RD-DDBK3 User Manual
MCP1630V BIDIRECTIONAL 4 CELL
LI-ION CHARGER REFERENCE
DESIGN USER’S GUIDE
© 2006 Microchip Technology Inc.
DS51641A-page 7
Chapter 2. Installation and Operation
2.4
INTRODUCTION
The MCP1630V Bidirectional 4 Cell Li-Ion Charger Reference Design demonstrates
Microchip's high speed pulse width modulator (PWM) used in a four cell Li-Ion battery
charger combined power supply application. When used in conjunction with a micro-
controller, the MCP1630V will control the power system duty cycle to provide regulated
output voltage or current. The PIC16F88 microcontroller oscillator output is used to pro-
vide pulses at switching frequency of 500 kHz. The MCP1630V generates duty cycle
based on various external inputs. External signals include the input oscillator pulses
from PIC16F88, the reference voltage and the feed back voltage. The output signal is
a square wave pulse provided to the synchronous gate drive input. They synchronous
gate driver is used to turn on and off the upper buck MOSFET and lower synchronous
MOSFET.
The PIC16F88 microcontroller is programmable, allowing the user to modify or develop
their own firmware routines to further evaluate the MCP1630V in this application.
Microchip's high speed pulse width modulator (PWM) used in a four cell Li-Ion battery
charger combined power supply application. When used in conjunction with a micro-
controller, the MCP1630V will control the power system duty cycle to provide regulated
output voltage or current. The PIC16F88 microcontroller oscillator output is used to pro-
vide pulses at switching frequency of 500 kHz. The MCP1630V generates duty cycle
based on various external inputs. External signals include the input oscillator pulses
from PIC16F88, the reference voltage and the feed back voltage. The output signal is
a square wave pulse provided to the synchronous gate drive input. They synchronous
gate driver is used to turn on and off the upper buck MOSFET and lower synchronous
MOSFET.
The PIC16F88 microcontroller is programmable, allowing the user to modify or develop
their own firmware routines to further evaluate the MCP1630V in this application.
2.5
FEATURES
The MCP1630V Bidirectional 4 Cell Li-Ion Charger Reference Design has the following
features:
• Four Cell Li-Ion Battery Charger, operates stand alone. (Additional firmware
features:
• Four Cell Li-Ion Battery Charger, operates stand alone. (Additional firmware
added allows the charger to communicate with smart battery packs)
• Charges four cell Li-Ion battery pack from 6.5V to 7.0V Input (complete
precondition, constant current and constant voltage charge algorithm in firmware)
• Regulates input dc bus voltage, (steps battery pack voltage down), to 6.0V when
input source is removed (providing uninterrupted power source for system)
• ON/OFF button used to enable and disable system, low I
Q
drain on the battery
when disabled (< 10 µA)
• Output over-voltage protection in the event of open battery connections
• High efficiency over entire operating input voltage range (94% typical)
• PIC16F88 is used to generate ref Voltage and Oscillator signal at 500 kHz
• High efficiency over entire operating input voltage range (94% typical)
• PIC16F88 is used to generate ref Voltage and Oscillator signal at 500 kHz
frequency at maximum duty cycle
• Proprietary features can be added by modifying the firmware contained in the
PIC16F88
• Factory programmed source code is available