Abstract: Compensation circuitry includes a resistor and transistor coupled in series with a reference current source to generate a variable reference voltage that is provided, via a voltage regulator, to bias elements of a core circuit in order to establish an operating current in the core circuit. In one embodiment, the resistor and transistor of the compensation circuitry are of similar construction to the bias elements of the core circuit, such that fluctuations in the ratio of the reference current and the operating current of the core circuit are minimized over process, supply voltage and temperature variations. The voltage regulator may be a low dropout regulator. In various embodiments, the core circuit may comprise a resistor biased voltage controlled oscillator, a differential current mode logic (CML) input to single CMOS output circuit, or like circuitry that may be sensitive to phase noise or requires low power operation.