6

LTC1422

GATE (Pin 6): The high side gate drive for the external

N-Channel. An internal charge pump guarantees at least

10V of gate drive. The slope of the voltage rise or fall at the

GATE is set by an external capacitor connected between

GATE and GND, and the 10

µA charge pump output cur-

rent. When the circuit breaker trips, the undervoltage

low for more than 40

µs, the GATE pin is immediately

pulled to GND.

SENSE (Pin 7) : Circuit Breaker Set Pin. With a sense

the circuit breaker will trip when the voltage across the

resistor exceeds 50mV for more than 10

µs. If the circuit

breaker trip current is set to twice the normal operating

current, only 25mV is dropped across the sense resistor

during normal operation. To disable the circuit breaker,

undervoltage lockout circuit disables the chip until the

1.232V

REFERENCE

GLITCH

FILTER

10

µs

FILTER

2.47V

UVL

50mV

8

REF

5

FB

1

RESET

4

GND

COMP 3

7

SENSE

6

GATE

–

+

COMP 1

REF

COMP 2

2

µA

12

µA

–

+

COMP 4

REF

TIMER

1422 BD

3

ON

2

Q1

Q2

LOGIC

CHARGE

PUMP

Q3

BLOCK DIAGRA