3 bit ADC

A 3-bit Analog to Digital Converter (ADC) that should in theory have a range of 111 at 5.6V. LSB -> starts with the LED on the right MSB -> the last LED on the left 000 bit -> 0V to 800mV 001 bit -> 800mV to 1.6V 010 bit -> 1.6V to 2.4V 011 bit -> 2.4V to 3.2V 100 bit -> 3.2V to 4V 101 bit -> 4V to 4.8V 110 bit -> 4.8V to 5.6V 111 bit -> higher than 5.6V You can change the voltage value of the second source 1.71V during simulation, to see how the bits change in real time. OpAmps are ideally 0V (low) to 5V (high), with a linear gain of 10kV/V in open loop equal to 80dB in logarithmic scale. The trick is to pair every bit column that are high with an OR gate, but the problem is due to voltage dividing, once you hit a threshold all the previous values remain high at the OpAmps output. For that you need an inverter and a couple of AND gates.

published 9 months ago