MT6M15962a
© Fuji Electric Co., Ltd. All rights reserved.
5.9 IGBT chip temperature warning output operation
• A chip temperature warning signal is output before the switching operation is stopped by IGBT chips
over heating protection. During this time, the switching operation continues.
• When the IGBT chip surface temperature
T
vj
reaches the IGBT chips warning temperature level
T
jW
,
the
T
vj
warning signal output terminal voltage changes from
V
CC
to 0V. During this time, the switching
operation continues. (1)
• When
T
vj
falls below
T
jW
, the
T
vj
warning signal output terminal voltage returns to
V
CC
. (2)
• Next, if
T
vj
exceeds
T
jOH
in the state of (1), an alarm signal is output and the switching operation is
stopped. (3)
V
CC
: Supply voltage of pre-driver
T
jOH
: IGBT chips over heating protection temperature level
3-23
Fig.3-17 Chip temperature warning operation
Warning signal
output terminal
Switching
operation
Over heating protection
alarm output terminal
Warning signal output period
Alarm output period
Stop period
(1)
(3) (2)
Over heating
protection level
T
jOH
IGBT chips warning
temperature level
T
jW
Over heating
protection reset level
Warning temperature
reset level
