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Parallel-Encoding ADC (flash ADC)

The parallel-encoding or flash ADC design provides the fastest operation at the expense of high component count and high cost (figure 8.5).

Figure 8.5:  A 3-bit, parallel-encoding or flash ADC.

The resistor network sets discrete thresholds for a number of comparators. All comparators with thresholds above the input signal go false while those below go true. Then digital encoding logic converts the result to a digital number.

Doug Gingrich
Tue Jul 13 16:55:15 EDT 1999