A charge pump oscillator circuit with compensation for variations in process
and
operating environment. The charge pump oscillator is designed with a rolloff characteristic
that enables operation at both weak and strong process corners without excessive
power consumption. Composite resistors in the oscillator circuit are composed of
component resistors that are fabricated with different processes, e.g., implant
and deposition. The resistance of the composite resistor is thus in order to provide
compensation for variations in processing and operating environment. The composite
resistor may be used as a feedback loop resistor, or may be used as a source degenerate
resistor to control the supply current to the oscillator.
