Method to achieve constant slew rate (over process corners) for an output buffer

摘要

An apparatus comprising a first circuit, a state machine, a compare circuit and a calibration circuit. The first circuit may be configured to generate a slew rate control signal and a calibration signal in response to (i) a plurality of control bits and (ii) an operation signal. The state machine may be configured to generate the operation signal and a plurality of intermediate control signals in response to (i) a compare signal and (ii) clock signal. The compare circuit may be configured to generate the compare signal in response to (i) a reference voltage and (ii) a capacitance signal. The calibration circuit may be configured to generate the capacitance signal in response to (i) the calibration signal and (ii) the plurality of intermediate control signals.