Bipolar Integration of a Floating Current Source
Original Publication Date: 1983-Sep-01
Included in the Prior Art Database: 2005-Feb-07
This article relates to the embodiment of a floating current source from a single-ended sink and a single-ended source to get the equivalent of a MOS transistor. Unlike conventional bipolar current sinks or sources which have a high impedance terminal and a low impedance one, the two terminals of the source described below are high impedance terminals. This is done by synthesizing a complementary transistor by compounding several PNP and NPN transistors. Two NPN transistors T1 and T2 with current gains b1N and b2N are serially connected between nodes A and B with a current mirror circuit made of transistor T3 and T4 with transfer ratio bp equal to 1 and emitter-to-collector current gain ap.