AN578

2/5

Figure 2. Voltage and current for a non-firing device

b) In the second operating region the LCPxxx fires and the piece under test is still functional after 15 min-

utes.

– Figure 3.1 shows the start of the firing (the peak of the current wave through the device is just over the

latching limit).

– Figure 3.2 the amplitude of the current wave through the device is greater than in the precedent case,

so the device is well fired after a few hundred microseconds.

c) In the third operating region the device has been destoyed in a time depending on the current through

the LCPxxx.

Figure 3. Equivalent circuit of both driver and receiver adjacent lines

0V

-48V

0A

Voltage between line A and GND.

Current through the line A

0V

-48V

0V

-48V