MCP73861/2/3/4
3.0
PIN DESCRIPTION
The descriptions of the pins are listed in Table 3-1.
TABLE 3-1:
Pin No.
PIN FUNCTION TABLES
Symbol
Function
QFN
SOIC
1
2
3
4
V
V
V
V
Voltage Regulation Selection
Battery Management Input Supply
Battery Management Input Supply
Battery Management 0V Reference
Current Regulation Set
SET
DD1
DD2
SS1
3
5
4
6
5
7
PROG
THREF
THERM
TIMER
6
8
Cell Temperature Sensor Bias
Cell Temperature Sensor Input
Timer Set
7
9
8
10
11
12
13
14
15
16
1
9
V
Battery Management 0V Reference
Battery Charge Control Output
Battery Charge Control Output
Battery Voltage Sense
SS3
10
11
12
13
14
15
16
V
V
V
BAT1
BAT2
BAT3
V
Battery Management 0V Reference
Logic Enable
SS2
EN
STAT2
STAT1
Fault Status Output
2
Charge Status Output
3.1
Voltage Regulation Selection
(V
3.7
Timer Set
)
All safety timers are scaled by CTIMER/0.1 µF.
SET
MCP73861/3: Connect VSET to VSS for 4.1V regulation
voltage, connect to VDD for 4.2V regulation voltage.
MCP73862/4: Connect VSET to VSS for 8.2V regulation
voltage, connect to VDD for 8.4V regulation voltage.
3.8
Battery Charge Control Output
(V , V
)
BAT2
BAT1
Connect to positive terminal of battery. Drain terminal
of internal P-channel MOSFET pass transistor. Bypass
to VSS with a minimum of 4.7 µF to ensure loop stability
when the battery is disconnected.
3.2
Battery Management Input Supply
(V , V
)
DD1
DD2
A supply voltage of [VREG (typ.) + 0.3V] to 12V is
recommended. Bypass to VSS with a minimum of
4.7 µF.
3.9
Battery Voltage Sense (V
)
BAT3
VBAT3 is a voltage sense input. Connect to positive
terminal of battery. A precision internal resistor divider
regulates the final voltage on this pin to VREG
3.3
Battery Management 0V Reference
(V , V , V
.
)
SS3
SS1
SS2
3.10 Logic Enable (EN)
Connect to negative terminal of battery and input
supply.
EN is an input to force charge termination, initiate
charge, clear faults or disable automatic recharge.
3.4
Current Regulation Set (PROG)
3.11 Fault Status Output (STAT2)
Preconditioning, fast and termination currents are
scaled by placing a resistor from PROG to VSS
STAT2 is a 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.
.
3.5
Cell Temperature Sensor Bias
(THREF)
THREF is a voltage reference to bias external
thermistor for continuous cell temperature monitoring
and prequalification.
3.12 Charge Status Output (STAT1)
STAT1 is a 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.
3.6
Cell Temperature Sensor Input
(THERM)
THERM is an input for an external thermistor for contin-
uous cell-temperature monitoring and prequalification.
Connect to THREF/3 to disable temperature sensing.
DS21893C-page 12
© 2005 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
