BEHLMAN BL10000 Series, User'S Manual And Technical Reference Manual

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APPENDIX A
IGBT DRIVER
The insulated gate bipolar transistor (IGBT) driver is a hybrid IC that is used in the over-current detector circuit
of each BL5000 unit. Two of these drivers are used in each unit to provide signal isolation, over-current
detection, and low-speed over-current cutoff features. Figure 1 shows the internal parts of an IGBT driver and
its pin descriptions.
SIGNAL ISOLATION - A photo-coupler with a high isolation voltage is used for signal isolation.
OVER-CURRENT DETECTION - The IGBT driver can withstand an over-current of 10 µsec duration when
short circuited. An extremely fast protection circuit is used here for this reason.
LOW-SPEED OVER-CURRENT CUTOFF - A low-speed cutoff circuit slowly turns off the IGBT driver in
response to an over-current sensing. This feature protects the IGBT against damage from high voltage spikes
generated during normal drive speed cutoffs.
PIN DESCRIPTION
1 Connected to smoothing
capacitor for reverse bias
power supply.
2 Power supply (+20 Vdc).
3 Drive output.
4 Not connected.
5 Over-current detection
output.
6 Collector voltage
monitoring.
7,8 Not connected.
9 Power supply (0 Vdc).
10-13 Not connected.
14 Drive signal input (-).
15 Drive signal input (+).
Figure 1. IGBT Driver, Pin Description and Schematic
A-1