MICROPOWER CMOS ASTABLE SAVES POWER WITH FOUR-LAYER DIODE.

A free-running CMOS multivibrator with a four-layer diode consumes only 3 mu a - about a hundred times less than more conventional designs. Ordinary designs dissipate about 5 mw, which is far too much for long-term operation from a small battery. This relatively high power consumption occurs because the IC's input stays in a transition region between its upper and lower thresholds for quite a long time. While the input is in this transition region, current from the battery flows to ground through both the upper and the lower transistors in the IC. Far less power is drained, however, if the input to the IC passes quickly through the transition region. The four-layer diode in the free-running multivibrator causes the input voltage to the IC to change states abruptly, rather than gradually.