10

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FSBB30CH60 Rev. B

(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 8. 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 tim e

constant delay

SC

Protection

circuit state

SET

RESET

c6 c7

c3

c2

c1

c8

c4

c5