Base-emitter voltage difference circuit for forming resistorless proportional to absolute temperature unit cell in cascading voltage reference circuit, has metal-oxide semiconductor transistor for controlling collector voltage of transistor

摘要

The circuit (50) has current sources (101, 102) for supplying current to bipolar transistors (15, 16). A metal oxide semiconductor (MOS) transistor is connected between emitters of the bipolar transistors and in a feedback loop to a collector of one of the bipolar transistors to generate proportional to absolute temperature (PTAT) voltage as difference between base-emitter voltages of the bipolar transistors in accordance with collector current density ratio of the bipolar transistors. Another MOS transistor controls collector voltage of the other bipolar transistor. The MOS transistor is divided into p-type MOS (PMOS) transistors (11, 12) and n-type MOS (NMOS) transistors (13, 14). An independent claim is also included for a cascading circuit.