All it's measuring is for a voltage spike. The ones we had had a real input pin and a test input pin. You hook up an O'scope to the output, supply a one-shot

All it's measuring is for a voltage spike. The ones we had had a real input pin and a test input pin. You hook up an O'scope to the output, supply a one-shot signal to the test pin, and check to make sure the output did what it was supposed to in the allotted time.