Suppose that a 3- digit BCD digital- to- analog converter has a full- scale output of 49.95 mA. What is the percentage resolution of the DAC?
A) 0.02%
B) 0.20%
C) 0.10%
D) 0.01%

Question

Quizplus · Accepted Answer

The resolution of a DAC is given by the formula: Resolution = (1 / 2^n) * 100%, where n is the number of bits. For a 3-digit BCD, each digit is represented by 4 bits, so n = 3*4 = 12 bits. Therefore, Resolution = (1 / 2^12) * 100% = (1 / 4096) * 100% ≈ 0.0244%. However, since this specific value is not an option and considering the context of a 3-digit BCD DAC with a full-scale output of 49.95 mA, the resolution in terms of current would be 49.95 mA / 999 (since 999 is the maximum value a 3-digit BCD can represent) ≈ 0.05 mA. To find the percentage resolution relative to the full-scale output: (0.05 mA / 49.95 mA) * 100% ≈ 0.10%. This approximation aligns with the understanding that the resolution in terms of percentage of full scale is the more relevant measure in this context, leading to option C being the correct choice.

Suppose That a 3- Digit BCD Digital- To- Analog Converter