Gain and offset correction in an interpolation ADC

摘要

In described examples, an analog to digital converter (ADC) includes a main ADC and a reference ADC. The main ADC generates a zone information signal and a digital output in response to an input signal. The reference ADC receives a plurality of reference voltages from the main ADC. The plurality of reference voltages includes a first reference voltage and a second reference voltage. The reference ADC generates a reference output in response to the input signal, the first reference voltage and the second reference voltage. A subtractor generates an error signal in response to the digital output and the reference output. A logic block generates one of a first offset correction signal, a second offset correction signal and a gain mismatch signal in response to the zone information signal, the error signal and the reference output.

主权项

1. An analog to digital converter (ADC) comprising:
a main ADC configured to generate a zone information signal and a digital output in response to an input signal; a reference ADC configured to receive a plurality of reference voltages from the main ADC, the plurality of reference voltages includes a first reference voltage and a second reference voltage, and the reference ADC configured to generate a reference output in response to the input signal, the first reference voltage and the second reference voltage; a subtractor configured to generate an error signal in response to the digital output and the reference output; and a logic block coupled to the main ADC, the reference ADC and the subtractor, the logic block configured to generate one of a first offset correction signal, a second offset correction signal and a gain mismatch signal in response to the zone information signal, the error signal and the reference output.