WESTCODE An IXYS Company
Fast Symmetrical Gate Turn-Off Thyristor type H0500KC25#
1.7 Critical rate of rise of on-state current
The value given is the maximum repetitive rating, but does not imply any specific operating condition. The
high turn-on losses associated with limit di/dt would not allow for practical duty cycle at this maximum
condition. For special pulse applications, such as crowbars and pulse power supplies, a much higher di/dt
is possible. Where the device is required to operate with infrequent high current pulses, with natural
commutation (i.e. not gate turn-off), then di/dt>5kA/µs is possible. For this type of operation individual
specific evaluation is required.
1.8 Gate ratings
The absolute conditions above which the gate may be damaged. It is permitted to allow VGK(AV) during turn-
off (see diagram 10) to exceed VRGM which is the implied DC condition.
1.9 Minimum permissible off time.
This time relates specifically to re-firing of device (see also note on gate-off time 2.7). The value given in
the ratings applies only to operating conditions of ratings note 2. For other operating conditions see the
curves of figure 18.
1.10 Minimum permissible on-time.
Figure is given for minimum time to allow complete conduction of all the GTO thyristor islands. Where a
simple snubber, of the form given in diagram 1. (or any other non-energy recovery type which discharges
through the GTO at turn-on) the actual minimum on-time will usually be fixed by the snubber circuit time
constant, which must be allowed to fully discharge before the GTO thyristor is turned off. If the anode
circuit has di/dt<10A/µs then the minimum on-time should be increased, the actual value will depend upon
the di/dt and operating conditions (each case needs to be assessed on an individual basis).
Data Sheet. Type H0500KC25# Issue 2
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