Method for testing differential analog-to-digital converter and system therefor

A method for testing an analog-to-digital converter (ADC), the method comprising:

• coupling an output of an analog signal source to a differential input of an amplifier;
• coupling a differential output of the amplifier to a differential input of the ADC;
• providing a test signal from the output of the analog signal source to the differential input of the amplifier;
• coupling an offset voltage to the differential output of the amplifier;
• amplifying the test signal to generate an amplified and offset differential signal at the differential output of the amplifier;
• providing the amplified and offset differential signal to the differential input of the ADC;
• and
• determining if an output of the ADC is as expected.

A differential amplifier stage comprising:

• a single-ended input for being coupled to a single-ended output of a digital-to-analog converter (DAC);
• a first switch having a first terminal coupled to the single-ended input, and a second terminal;
• a first capacitor having a first terminal coupled to the second terminal of the first switch, and a second terminal;
• a second switch having a first terminal coupled to the single-ended input, and a second terminal;
• a second capacitor having a first terminal coupled to the second terminal of the second switch, and a second terminal;
• and
• a differential amplifier having a first differential input coupled to the second terminal of the first capacitor, and a second differential input coupled to the second terminal of the second capacitor.