Abstract: A system for compensating for thermal drift of an output signal (OUT1) produced by a logic circuit in response to an input CLOCK signal after a temperature dependent delay includes a variable delay circuit, an oscillator and a digital phase lock controller. The delay circuit delays the OUT1signal to produce a compensated output signal (OUT2) with a variable delay controlled by input CONTROL data. The oscillator generates an output signal (OSC.sub.-- OUT) having a period also controlled by the input CONTROL data which is substantially proportional to the sum of the temperature dependent delay of the logic circuit and the delay of the variable delay circuit. The digital phase lock controller continually monitors the period of the OSC.sub.-- OUT signal and adjusts the CONTROL data so that the period of the OSC.sub.-- OUT signal remains substantially constant. This ensures that the delay between the CLOCK signal and OUT2 remains constant despite temperature dependent variations in the delay of the logic circuit.