Datasheet

© 2009 Microchip Technology Inc. DS22005B-page 13
MCP73833/4
4.0 FUNCTIONAL DESCRIPTION
The MCP73833/4 is a highly advanced linear charge
management controller. Refer to the functional block
diagram and Figure 4-1 that depicts the operational
flow algorithm from charge initiation to completion and
automatic recharge.
FIGURE 4-1: Flow Chart.
V
BAT
< V
PTH
* Continuously Monitored
Timer Expired
SHUTDOWN MODE *
V
DD
< V
UVLO
V
DD
< V
BAT
STAT1 = HI-Z
STAT2 = HI-Z
PG = HI-Z
STANDBY MODE *
V
BAT
(V
REG
+ 100 mv)
PROG > 200 kΩ
STAT1 = HI-Z
STAT2 = HI-Z
PG = LOW
SYSTEM TEST (LDO) MODE
V
THERM
> (V
DD
- 100 mv)
PROG > 20 kΩ
STAT1 = LOW
STAT2 = LOW
PG = LOW
Timer Suspended
TEMPERATURE FAULT
No Charge Current
STAT1 = Hi-Z
STAT2 = Hi-Z
PG = LOW
Timer Suspended
TIMER FAULT
No Charge Current
STAT1 = Hi-Z
STAT2 = Hi-Z
PG = LOW
Timer Suspended
PRECONDITIONING MODE
Charge Current (I
PREG
STAT1 = LOW
STAT2 = Hi-Z
PG = LOW
Timer Reset
FAST CHARGE MODE
Charge Current (I
REG
STAT1 = LOW
STAT2 = Hi-Z
PG = LOW
Timer Enabled
CONSTANT VOLTAGE MODE
Charge Voltage (V
REG
STAT1 = LOW
STAT2 = Hi-Z
PG = LOW
CHARGE COMPLETE MODE
No Charge Current
STAT1 = HI-Z
STAT2 = LOW
PG = LOW
Timer Reset
V
BAT
> V
PTH
V
BAT
= V
REG
V
BAT
< I
TERM
Timer Expired
V
BAT
> V
PTH
V
BAT
< V
RTH