Control circuit having stacked ic logic

Abstract

A stacked logic circuit ( ) having a serially connected first logic circuit ( ) operating off a first voltage differential and providing in series with a second logic circuit ( ) operating off a second voltage differential. The second logic circuit being in series with the first logic circuit recycles the current of the first logic circuit. A low impedance shunt circuit ( ) is provided in parallel with the first logic circuit ( ) and shunts additional current required of and to the second logic circuit ( ) from the single voltage source (V ). A Zener diode (Z ) shunts current from the first logic circuit not required by the second logic circuit via a shunt node (N). The shunt circuit ( ) includes a Darlington pair of transistors or a three terminal voltage regulator ( ) and only shunts a very small amount of current to ground. The stacked logic circuit of the present invention efficiently uses current drawn by the single voltage source to reduce power consumption.