The successive-approximation converter is one of the most widely used types of ADC It has more complex circuitry than the digital-ramp ADC but a much shorter conversion time In addition successive-approximation converters have a fixed value of conversion time that is not dependent on the value of the analog input
The basic arrangement shown in Figure 5. Is similar to that of the digital-ramp ADC The SAC however does not use a counter to provide the input to the DAC block but uses a register instead. The control logic modifies the contents of the register bit by bit until the register data are the digital equivalent of the analog input Va within the resolution of the converter The basic sequence of operation is given by the flowchart in Figure 5. We will follow this flowchart as we go through the example illustrated in Figure 5.