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FSBB20CH60CT Rev. C

(with the external shunt resistance and CR connection)

c1 : Normal operation: IGBT ON and carrying current.

c2 : Short circuit current detection (SC trigger).

c3 : Hard IGBT gate interrupt.

c4 : IGBT turns OFF.

c6 : Input “L” : IGBT OFF state.

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

c8 : IGBT OFF state

Figure 10. Short-Circuit Current Protection (Low-side Operation only)

Internal IGBT

Gate-Emitter Voltage

Lower arms

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