Sixteen-Input Funnel Utilizing Five-Level Differential Cascode Current Switch
Original Publication Date: 1983-Dec-01
Included in the Prior Art Database: 2005-Feb-08
Cascode current switch (CCS) circuitry consists of reference level and differential types. Typically, one or two level CCS circuitry is reference level and utilizes dotting to obtain the desired function while 3 to 8 level CCS circuitry is of the differential type and does not generally utilize output dotting. It requires both input phases to be available and generates both output phases of the desired function if no output dotting is used. With present 5-volt semiconductor technology, 5-level CCS circuitry best utilizes the VBE drop across a transistor. This allows a maximum of 5 input variables for each Term (Boolean expression) used in a differential cascode current switch (DCCS) circuit (one current source).