MCP73861/2
DS21893B-page 12 2005 Microchip Technology Inc.
3.0 PIN DESCRIPTION
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1: PIN FUNCTION TABLES
3.1 Voltage Regulation Selection
(V
SET
)
MCP73861: Connect to V
SS
for 4.1V regulation
voltage, connect to V
DD
for 4.2V regulation voltage.
MCP73862: Connect to V
SS
for 8.2V regulation
voltage, connect to V
DD
for 8.4V regulation voltage.
3.2 Battery Management Input Supply
(V
DD2
, V
DD1
)
A supply voltage of [V
REG
(Typ) + 0.3V] to 12V is
recommended. Bypass to V
SS
with a minimum of
4.7 µF.
3.3 Battery Management 0V Reference
(V
SS1
, V
SS2
, V
SS3
)
Connect to negative terminal of battery and input
supply.
3.4 Current Regulation Set (PROG)
Preconditioning, fast and termination currents are
scaled by placing a resistor from PROG to V
SS
.
3.5 Cell Temperature Sensor Bias
(THREF)
Voltage reference to bias external thermistor for
continuous cell temperature monitoring and
prequalification.
3.6 Cell Temperature Sensor Input
(THERM)
Input for an external thermistor for continuous cell-
temperature monitoring and prequalification. Connect
to THREF/3 to disable temperature sensing.
3.7 Timer Set
All safety timers are scaled by C
TIMER
/0.1 µF.
3.8 Battery Charge Control Output
(V
BAT1
, V
BAT2
)
Connect to positive terminal of battery. Drain terminal
of internal P-channel MOSFET pass transistor. Bypass
to V
SS
with a minimum of 4.7 µF to ensure loop stability
when the battery is disconnected.
3.9 Battery Voltage Sense (V
BAT3
)
Voltage sense input. Connect to positive terminal of
battery. A precision internal resistor divider regulates
the final voltage on this pin to V
REG
.
3.10 Logic Enable (EN)
Input to force charge termination, initiate charge, clear
faults or disable automatic recharge.
3.11 Fault Status Output (STAT2)
Current-limited, open-drain drive for direct connection
to a LED for charge status indication. Alternatively, a
pull-up resistor can be applied for interfacing to a host
microcontroller.
3.12 Charge Status Output (STAT1)
Current-limited, open-drain drive for direct connection
to a LED for charge status indication. Alternatively, a
pull-up resistor can be applied for interfacing to a host
microcontroller.
Pin No.
Symbol Function
QFN SOIC
13 V
SET
Voltage Regulation Selection
24 V
DD1
Battery Management Input Supply
35 V
DD2
Battery Management Input Supply
46 V
SS1
Battery Management 0V Reference
5 7 PROG Current Regulation Set
6 8 THREF Cell Temperature Sensor Bias
7 9 THERM Cell Temperature Sensor Input
810 TIMERTimer Set
911 V
SS3
Battery Management 0V Reference
10 12 V
BAT1
Battery Charge Control Output
11 13 V
BAT2
Battery Charge Control Output
12 14 V
BAT3
Battery Voltage Sense
13 15 V
SS2
Battery Management 0V Reference
14 16 EN Logic Enable
15 1 STAT2 Fault Status Output
16 2 STAT1 Charge Status Output
