MCP73833_09 Datasheet, PDF (11/32 Pages) Microchip Technology – Stand-Alone Linear Li-Ion / Li-Polymer Charge Management Controller

MCP73833/4
3.0 PIN DESCRIPTIONS
Descriptions of the pins are listed in Table 3-1.
TABLE 3-1: PIN FUNCTION TABLE
Pin No.
DFN-10 MSOP-10
Symbol
Function
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10
10
11
—
V_DD
V_DD
STAT1
STAT2
V_SS
PROG
PG, TE
THERM
V_BAT
V_BAT
EP
Battery Management Input Supply
Battery Management Input Supply
Charge Status Output
Charge Status Output
Battery Management 0V Reference
Current Regulation Set and Charge Control Enable
MCP73833: Power Good output, MCP73834: Timer Enable input
Thermistor input
Battery Charge Control Output
Battery Charge Control Output
Exposed Thermal Pad (EP); must be connected to V_SS.
3.1 Battery Management Input Supply
(V_DD)
A supply voltage of [V_REG (typical) + 0.3V] to 6V is
recommended. Bypass to V_SS with a minimum of 1 µF.
3.2 Charge Status Outputs (STAT1,
STAT2)
STAT1 and STAT2 are open-drain logic outputs for con-
nection to a LED for charge status indication.
Alternatively, a pull-up resistor can be applied for
interfacing to a host microcontroller.
3.3 Battery Management 0V Reference
(V_SS)
Connect to negative terminal of battery and input
supply.
3.4 Current Regulation Set (PROG)
Preconditioning, fast charge, and termination currents
are scaled by placing a resistor from PROG to V_SS.
The charge management controller can be disabled by
allowing the PROG input to float.
3.5 Power Good Indication (PG)
MCP73833 Only
The power good (PG) option is a pseudo open-drain
output. The PG output can sink current, but not source
current. However, there is a diode path back to the
input, and, as such, the PG output should only be
pulled up to the input. The PG output is low whenever
the input to the MCP73833 is above the UVLO
threshold and greater than the battery voltage.
3.6 Timer Enable Input (TE)
MCP73834 Only
The timer enable (TE) input option is used to enable or
disable the internal timer. A low signal on this pin
enables the internal timer and a high signal disables
the internal timer. The TE input can be used to disable
the timer when the charger is supplying current to
charge the battery and power the system load. The TE
input is compatible with 1.8V logic.
3.7 Thermistor Input (THERM)
An internal 50 µA current source provides the bias for
most common 10 kΩ negative-temperature coefficient
thermistors (NTC). The MCP73833/4 compares the
voltage at the THERM pin to factory set thersholds of
1.20V and 0.25V, typically.
3.8 Battery Charge Control Output
(V_BAT)
Connect to positive terminal of battery. Drain terminal
of internal P-channel MOSFET pass transistor. Bypass
to V_SS with a minimum of 1 µF to ensure loop stability
when the battery is disconnected.
3.9 Exposed Thermal Pad (EP)
There is an internal electrical connection between the
Exposed Thermal Pad (EP) and the V_SS pin; they must
be connected to the same potential.
© 2009 Microchip Technology Inc.
DS22005B-page 11