Datasheet

MCP73837/8

3.8 USB-Port Current Regulation Set

(PROG2)

The MCP73837/8 USB-port current regulation set input

(PROG2) is a digital input selection. A logic Low selects

a 1 unit load charge current; a logic High selects a 5

unit loads charge current. The precondition and

termination current is internally set to the percentage

levels selected by the device part number. The current

is based upon the selected unit load charge current

based upon the level of PROG2.

PROG2 also functions as the set point of termination

when USB-port is present. When PROG2 is floating,

the MCP73837/8 enters in Stand-by mode.

3.9 Power Good (PG)

Power Good (PG) is available only on MCP73837. PG

is an open-drain logic output for connection to an LED

for input power supply indication. Alternatively, a pull-

up resistor can be applied for interfacing to a host

microcontroller.

3.10 Timer Enable (TE)

Timer Enable (TE) is available only on MCP73838.

(TE

) enables the built-in safety timer when pull low and

disables the built-in safety timer when pull high.

Note: The built-in safety timer is available for both

MCP73837 and MCP73838 in the following

options: Disable, 4 HR, 6 HR, and 8 HR.

3.11 Battery Temperature Monitor

(THERM)

MCP73837/8 continuously monitors the battery

temperature during a charge cycle by measuring the

voltage between the THERM and V

pins. An internal

50 µA current source provides the bias for the most

common 10 kΩ negative-temperature coefficient

thermistors (NTC).