Page 998 - Basic Electrical Engineering
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current to I , V AK required to make the device conducting is again reduced.
g2
This process is called gate control process.
Under the reverse-biased condition, the device is in blocking state because
two of its junctions are reverse biased and a large barrier potential is built up
across the junctions. But upon increasing the reverse voltage to V BDR , there is
a breakdown of junctions. The device starts conducting in the opposite
direction and a large reverse current starts flowing. The reverse current is so
large that it will damage the SCR. That is why an SCR is not operated in the
reverse conduction mode.
Figure 14.36 V–I characteristic of an SCR
