Datasheet

© 2009 Microchip Technology Inc. DS22005B-page 15
MCP73833/4
4.7 Automatic Recharge
The MCP73833/4 continuously monitors the voltage at
the V
BAT
pin in the charge complete mode. If the
voltage drops below the recharge threshold, another
charge cycle begins and current is once again supplied
to the battery or load. The recharge threshold is factory
set. Refer to Section 1.0 “Electrical Characteristics”
for recharge threshold options.
4.8 Thermal Regulation
The MCP73833/4 limits the charge current based on
the die temperature. The thermal regulation optimizes
the charge cycle time while maintaining device
reliability. Figure 4-2 depicts the thermal regulation for
the MCP73833/4.
FIGURE 4-2: Thermal Regulation.
4.9 Thermal Shutdown
The MCP73833/4 suspends charge if the die
temperature exceeds +150°C. Charging will resume
when the die temperature has cooled by approximately
+10°C. The thermal shutdown is a secondary safety
feature in the event that there is a failure within the
thermal regulation circuitry.
0
200
400
600
800
1000
1200
25 35 45 55 65 75 85 95
105 115 125 135 145 155
Junction Temperature (°C)
Charge Current (mA)
R
PROG
= 1 k
Ω