Digital Signal Processing - Technical MCQs

Q1:

A binary-weighted-input digital-to-analog converter has a feedback resistor, Rf, of 12 k. If 50 A of current is through the resistor, voltage out of the circuit is ________.

A 0.6 V

B –0.6 V

C 0.1 V

D –0.1 V

ANS:B - –0.6 V

If you use positive reference voltage, which is assumed here, then output is negative because OPAMP is acting as inverting amplifier. For positive output, you need to use negative reference voltage.