Texas Instruments Incorporated
MAXIMUM VOLTAGE SELECTOR CIRCUIT HAVING ADAPTIVE CURRENT BIAS GENERATOR

Abstract:

A voltage selector circuit includes a voltage comparator, a multiplexer, and an adaptive current bias generator. The voltage comparator receives first and second input voltages, and outputs a comparator signal based on the first and second input voltages. The multiplexer selects a larger of the first and second input voltages in time based on first comparator signal. The adaptive current bias generator generates a bias current for the voltage comparator during a transition from a first state to a second state. The first input voltage is continuously larger than the second input voltage during the first state, and the second input voltage is continuously larger than the first input voltage in the second state. The bias current during the transition has a time-varying current level that is proportional to a time-varying difference between the first input voltage and the second input voltage during the transition.