other types of adc

other types of adc - Tracking ADC This is one of the more...

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This is one of the more interesting methods. Instead of just starting at a midpoint and then guessing a solution, this ADC uses an up/down counter. The counter is continuously clocked, and the up/down control line is driven by the output of the comparator. Tracking ADC
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Here is how it works: When the analog input signal exceeds the DAC output, the counter goes into the "up count" mode. When the DAC output exceeds the analog input, the counter switches into the "down count" mode. By doing this the DAC is always moving in the proper ‘direction’ to track the input voltage. One of the other interesting features about this ADC is that it will start the ‘search’ at the last point that was resolved. Tracking ADC
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never stable: it always switches between counts with every clock pulse, even with a perfectly stable analog input signal. This phenomenon is informally known as ‘ bit bobble’ . However ‘bit bobble’ can be overcome through the use of a shift register. For example, the counter's output may be latched through a parallel-in/parallel- out shift register only when the output changes by two or more steps. Building a circuit to detect two or more successive counts in the same direction
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other types of adc - Tracking ADC This is one of the more...

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