Patent ID: 6292123
Filing Date: 2001-09-18
Classification: H03K

Abstract:
A digital-to-analog converter (DAC) which derives power from a power source having a supply voltage Vdd, comprising:a digital circuit section including CMOS circuitry composed of p-channel and n-channel field effect transistors (FETs) characterized by respective threshold voltages, said digital circuit section connected to receive digital data,an analog output section connected to produce analog output signals corresponding to the digital values of said digital data,an all-CMOS circuit connected to provide an output reset signal to said digital circuit section during a power-on transition,an all-CMOS control circuit that includes PFET and NFET transistors connected to terminate said reset signal when an applied power signal has reached a voltage that exceeds a reference voltage by at least the greater of the threshold voltages of said PFET and NFET transistors, but less than the sum of said threshold voltages, andan FET-compatible circuit structure that is connected to establish said reference voltage.