REV2 Decimal SAR ADC - DVM

I discovered a great improvement to my decimal successive approximation type digital voltmeter! See the old version here: https://everycircuit.com/circuit/5334865438048256 If I redesigned the Successive Approximation Register so that it worked in BCD instead in binary, I could skip the whole binary to decimal process and connect the register output directly to the 7-segment decoders. Swell! If you'd like more info on how a successive approximation type voltmeter works, please check out my first circuit like this. https://everycircuit.com/circuit/6044286526947328 Just a brief description, this circuit is basically a glorified counter analog to digital converter (ADC). It uses a successive approximation register (SAR) to successively guess closer to the actual input voltage, much like a binary search algorithm. Specifications: Clock: 2khz Sample rate: 20ms or 50 samples per second. Accuracy: 100mV Error: ~100mV Range 0V to 9.9V OUTPUT NUMBER ~ BCD number stored in SAR If 7.3V is input, then SAR will find ~0111 0011= 73 Blue waveform: Approximation voltage Green waveform: Unknown voltage input Orange waveform: Clock Prev Circuit: https://everycircuit.com/circuit/4753647644442624 Next Circuit: https://everycircuit.com/circuit/5229632454131712

published 2 years ago