Datasheet

 2003-2013 Microchip Technology Inc. DS21823D-page 12
MCP73841/2/3/4
FIGURE 4-1: Operational Flow Algorithm - MCP73841 and MCP73842.
Preconditioning Phase
Charge Current = I
PREG
Reset Safety Timer
Yes
Initialize
No
Yes
V
BAT
> V
PTH
STAT1 = On
V
BAT
> V
PTH
Yes
V
DD
< V
UVLO
No
No
Safety Timer
Yes
Temperature OK
No
STAT1 = Flashing
Safety Timer Suspended
Charge Current = 0
Fault
Charge Current = 0
Reset Safety Timer
or EN Low
No
STAT1 = Flashing
Constant-Current
Charge Current = I
REG
Reset Safety Timer
V
BAT
= V
REG
No
No
Safety Timer
Yes
Temperature OK
Constant-Voltage Phase
Output Voltage = V
REG
I
OUT
< I
TERM
Yes
V
BAT
< V
RTH
Elapsed Timer
Charge Termination
Charge Current = 0
Reset Safety Timer
No
STAT1 = Off
Yes
Yes
Temperature OK
No
STAT1 = Flashing
Safety Timer Suspended
Charge Current = 0
Yes
Yes
V
DD
< V
UVLO
or EN Low
No
Yes
Yes
Temperature OK
No
STAT1 = Flashing
Charge Current = 0
Yes
No
STAT1 = Off
V
DD
> V
UVLO
Phase
Expired
Expired
No
STAT1 = Flashing
Safety Timer Suspended
Charge Current = 0
EN High
Expired
Note: The qualification parameters are continuously
monitored throughout the charge cycle.
Note
Note