Patent ID: 7679537

Claim:
A digital-to-analog converter (DAC) circuit, comprising: a processor coupled to receive a regulated direct current (DC) voltage and operable to at least selectively generate and supply a pulse width modulation (PWM) output signal; a DAC filter coupled to receive the PWM output signal and operable, in response thereto, to supply an analog output signal; a power supply coupled to receive a voltage trim signal and operable, in response thereto, to generate and supply the regulated DC voltage; and a trim circuit coupled to receive the regulated DC voltage and operable, in response thereto, to supply the voltage trim signal to the power supply, the trim circuit comprising: a precision reference circuit operable to supply a precision DC reference voltage; and an integrator circuit coupled to receive the regulated DC voltage and the precision DC reference voltage and operable, in response thereto, to supply the voltage trim signal.