An apparatus and method for providing a power supply compensated voltage
or current is presented. A supply compensated current and voltage source
utilizes a differential amplifier connected to a bandgap reference
voltage and a scaled power supply voltage. When power supply varies, the
differential amplifier regulates a stable compensated output. The output
may be a compensated voltage or current. In addition, multiple currents
and voltages may be referenced from the differential amplifier. The
stable compensated output may be supplied as a reference bias for
external circuitry. In addition, the compensated output may be supplied
to a voltage controlled oscillator.