Microchip Technology MCP1630RD-DDBK3 Data Sheet

 2004-2013 Microchip Technology Inc.

DS21896C-page 13

When the input voltage (V

IN

) is less than the UVLO

threshold, the V

EXT

 is held in the low state. This will

ensure that, if the voltage is not adequate to operate
the MCP1630/V, the main power supply switch will be
held in the off state. When the UVLO threshold is
exceeded, there is some hysteresis in the input voltage
prior to the UVLO off threshold being reached. The
typical hysteresis is 75 mV. Typically, the MCP1630 will
not start operating until the input voltage at V

IN

 is

between 3.0V and 3.1V.

To protect the V

EXT

 output if shorted to V

IN

 or GND, the

MCP1630/V V

EXT

 output will be high-impedance if the

junction temperature is above the thermal shutdown
threshold. There is an internal 100 k

 pull-down resis-

tor connected from V

EXT

 to ground to provide some

pull-down during overtemperature conditions. The
protection is set to 150°C (typ.), with a hysteresis of
18°C.