Interfacing to the Analog World Questions

• When comparing the conversions from digital-to-analog and analog-to-digital, the A/D conversion is generally:
• What is the acquisition time of the AD1154 sample-and-hold IC?
• The primary disadvantage of the simultaneous A/D converter is:
• What is the speed of the up/down digital-ramp ADC (tracking ADC)?
• Electrical quantities can be interpreted without conditioning by a digital computer.
• An AD7524 is an eight-bit D/A converter that uses an R/2R ladder network.
• Two characteristics of ideal operational amplifiers are very high input impedance and very high voltage gain.
• The output voltage or current of a digital-to-analog converter is truly an analog signal.
• The amount of deviation of the measured step size from the ideal step size is a measure of linearity.
• In a digital storage scope, when memory is full, the next data point is lost.
• The current across the MSB "rung" of a 4-bit R/2R ladder DAC if the reference voltage is 5 v and R is 8 Ω is 625 µA.
• A sample-and-hold circuit is used in D/A conversion.
• When the inputs of a four-bit D/A converter are connected to a binary up-counter, the output looks like an upward sloping line.
• A data acquisition system may communicate via two common buses: the data bus and the control bus.
• The output of an analog-to-digital converter is a voltage level.
• When the analog input to a tracking A/D converter is at a constant level, the digital output will oscillate.
• A DAC is monotonic if its output increases as its binary input is incremented from one value to the next.
• To be useful, A/D or D/A converters must have meaningful representation of the analog quantity and a digital representation and the digital quantity as an analog representation.
• When a DAC output shows a deviation of the measured step size from the ideal step size, this error is called nonlinearity.
• An eight-bit D/A converter has a resolution of 0.125.