Analysis and detection of faults in emitter coupled logic (ECL) devices

Bipolar Emitter Coupled Logic (ECL) devices can be fabricated at very high densities and much lower power consumption. Analysis of faulty behavior in ECL devices exhibit stuck-at behavior and loss of complementarity. Delay faults as well as enhanced power supply current are also observed in ECL devices. A fault in ECL device manifesting as delay fault and exhibiting enhanced power supply current is shown. Detection of the above behavior under faults using logic monitoring requires careful and systematic generation of input vectors. Testing for delay faults is even more difficult. A power supply current monitor for detection of enhanced power supply current is presented.