WESTCODE An IXYS Company
Fast Symmetrical Gate Turn-Off Thyristor type H1200NC25#
Notes on ratings and characteristics.
1. Maximum Ratings.
1.1 Off-state voltage ratings.
Unless otherwise indicated, all off-state voltage ratings are given for gate conditions as diagram 1. For
other gate conditions see the curves of figure 5. It should be noted that VDRM is the repeatable peak
voltage which may be applied to the device and does not relate to a DC operating condition. While not
given in the ratings, VDC should ideally be limited to 60% VDRM in this product.
1.2 Reverse voltage rating.
All devices in this series have a minimum VRRM of 100 Volts. If specified at the time of order, a VRRM up to
80%VDRM is available.
1.3 Peak turn-off current.
The figure given in maximum ratings is the highest value for normal operation of the device under
conditions given in note 2 of ratings. For other combinations of ITGQ, VD and Cs see the curves of figures
15 & 16. The curves are effective over the normal operating range of the device and assume a snubber
circuit equivalent to that given in diagram 2. If a more complex snubber, such as an Underland circuit, is
employed then the equivalent CS should be used and Ls<0.3µH must be ensured for the curves to be
1.4 R.M.S and average current.
Measured as for standard thyristor conditions, double side cooled, single phase, 50Hz, 180° half-
sinewave. These are included as a guide to compare the alternative types of GTO thyristors available,
values can not be applied to practical applications, as they do not include switching losses.
1.5 Surge rating and I2t.
Ratings are for half-sinewave, peak value against duration is given in the curve of figure 4.
1.6 Snubber loop inductance.
Use of GTO thyristors with snubber loop inductance, Ls<0.3µH implies no dangerous Vs voltages (see
diagrams 2 & 3) can be applied, provided the other conditions given in note 1.3 are enforced. Alternatively
Vs should be limited to 700 Volts to avoid possible device failure.
Data Sheet. Type H1200NC25# Issue 2
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