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MT6M15962a
© Fuji Electric Co., Ltd. All rights reserved.
2-5
2.2.3 Protection circuit
Term
Symbol
Description
Over current protection
level
I
OC
Threshold current for overcurrent protection
Over current protection
delay time
t
dOC
Delay time from exceeding the over current protection trip level until
the protection starts. Refer to Figure 2-4.
Short circuit protection
operating current
I
SC
Threshold current for short-circuit protection
Short circuit protection
delay time
t
dSC
Delay time from exceeding the short-circuit protection trip level until
the protection starts. Refer to Figure 2-5.
IGBT chips over heating
protection temperature
level
T
jOH
Threshold junction temperature for over heating protection.
Over heating protection
hysteresis
T
jH
Temperature drop required for over heating protection to reset.
IGBT chips warning
temperature level
T
jW
IGBT chips temperature at which chips warning temperature signal is
output.
Warning hysteresis
T
jWH
Temperature drop required for chips warning temperature operation to
reset.
Under voltage protection
level
V
uv
Threshold voltage for under voltage protection.
Under voltage
protection hysteresis
V
H
Voltage that must exceed for under voltage protection to reset.
Alarm signal hold time
t
ALM(OC)
Alarm signal pulse width for overcurrent protection (OC)
t
ALM(UV)
Alarm signal pulse width for under voltage protection (UV)
t
ALM(TjOH)
Alarm signal pulse width for IGBT chips over heating protection (
T
jOH
)
Warning signal hold
time
t
WNG
Warning signal output time during chip temperature warning operation
Alarm signal voltage
V
ALMH
Alarm terminal voltage when protection is not operating
Warning signal Voltage
V
WNGH
Warning terminal voltage when chip temperature warning is not
operating.
Alarm output resistance
R
ALM
Value of the built-in resistance that is connected in series to alarm
terminals. It limits the primary side forward current of optocoupler.
Warning output
resistance
R
WNG
Value of the built-in resistance that is connected in series to warning
terminals. It limits the primary side forward current of optocoupler.