Tuesday, April 7, 2009

Microcontroller Switch-Mode Battery Charger Circuit


Microcontroller Battery Charger Circuit



In applications where a microcontroller is available, the
MAX1640/MAX1641 can be used as a low-cost battery
charger (Figure 5). The controller takes over fast
charge, pulse-trickle charge, charge termination, and
other smart functions. By monitoring the output voltage
at VOUT, the controller initiates fast charge (set D0 and
D1 high), terminates fast charge and initiates top-off
(set D0 high and D1 low), enters trickle charge (set D0
low and D1 high), or shuts off and terminates current
flow (set D0 and D1 low).
more pdf


MAX846A Li+ charger with charge timer and LED-status
outputs, controlled by an 8-pin Microcontroller



In this example, a small external µP enhances the MAX846A,
forming a complete desktop-charger system that includes
user-interface functions such as the LEDs in Figure (to indicate
the charge process and status). The MAX846A is designed for
this type of operation. Its auxiliary linear regulator and µP-reset
circuit (to support the external µC) reduces the cost of a typical
desktop-charger application.