Digital COmponents - Jargon Flashcards
(10 cards)
What is Full Scale Output?
Max current or voltage that can be outputted by a device. A DAC produces a full scale output voltage when the digital input is all 1’s.
What is Resolution in the context of a DAC?
The number of discrete steps in the output. This is dependent on the number of inputs; a 4-bit DAC will have a resolution of 2^4 - 1 = 15.
What is Conversion Time?
The time that elapses from the ‘start conversion’ command to the analog voltage appearing at the output.
What is Linearity?
Specified as the maximum deviation of the DAC output from a straight line output passing through zero and the full scale output.
What is Absolute Accuracy?
The largest difference between the actual output voltage and the ideal output voltage predicted. Quoted as a percentage of the full scale range or as a percentage of the LSB.
What is Differential Linearity Error?
The step size is more or less than the ideal step size.
What is Monotonicity in relation to a DAC?
Monotonicity is the relationship between the analog signal and the digital number. A DAC is monotonic if an increase in the input digital word always results in an increase in the output.
What is Settling Time in a DAC?
Settling Time is the time taken for the converter output to stabilize to within ± LSB of its final value after an input is applied. This can take from nanoseconds to microseconds.
What is Relative Accuracy in a DAC?
Relative Accuracy refers to how close each output level is to its ideal fraction of the full scale output.
What is Gain Error in a DAC?
Gain Error is an amplitude mismatch between the analog signal and the DAC. If too high, the DAC saturates for high codes. Too low, and the DAC accuracy is compromised
