A sub-2.0 V BiCMOS logic circuit with a BiCMOS charge pump

Abstract

A BiCMOS logic circuit with very small input capacitance has been developed, which operates at low supply voltages. A High-beta BiCMOS (H/spl beta/-BiCMOS) gate circuit which fully utilizes the bipolar transistor features achieves 10 times the speed of a CMOS gate circuit with the same input capacitance and operating at 3.3 V supply voltage. In order to lower the minimum supply voltage of H/spl beta/-BiCMOS, a BiCMOS circuit configuration using a charge pump to pull up the output high level of the BiCMOS gate circuit is proposed. By introducing a BiCMOS charge pump, H/spl beta/-BiCMOS achieves very high speed operation at sub-2.0 V supply voltage. It has also been demonstrated that only a very small number of charge pump circuits are required to drive a large number of H/spl beta/-BiCMOS gate circuits.