2-channel ADC tags its own output

The circuit in Fig 1 shows a simple way to operate a 1-MHz, 12-bit ADC (IC1) in DMA mode while alternating between its two analog-input channels. The converter operates continuously, driven by the 1-MHz clock on the S/H input. Tying RD and CS low ensures that data are always present on the ADC's output bus. The outputs of the 74HC74 flip-flop, IC2, change state on the rising edge of the end-of-conversion (EOC) signal.

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