©2013 Fairchild Semiconductor Corporation

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FSB70625 Rev. 1.2

Figure 6. Short-Circuit Current Protection

(with the external shunt resistance and CR connection)

c1 : Normal operation: MOSFET ON and carrying current.

c2 : Short circuit current detection (SC trigger).

c3 : Hard MOSFET gate interrupt.

c4 : MOSFET turns OFF.

c6 : Input “L” : MOSFET OFF state.

c7 : Input “H”: MOSFET ON state, but during the active period of fault output the MOSFET doesn’t turn ON.

c8 : MOSFET OFF state

Figure 7. Timing Chart of Interlock Function

Control input

Output Current

Sensing Voltage

of the shunt

resistance

Fault Output Signal

SC Reference Voltage

CR circuit time

constant delay

SC

Protection

Circuit state

SET

RESET

c6

c7

c3

c2

c1

c8

c4

c5

Internal MOSFET

Gate-Source Voltage

Hin

Lin

Ho

Lo