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It works! It is still painfully slow even after my changes to attempt to make it faster. So please give it time. This is a decimal version of the successive approximation digital volt meter I made before. It can read voltage up to around 10V with an accuracy of about 100mV.
INSTRUCTIONS:
The voltage source next to the opamp is the unknown. The 7-segment displays in the top right show the result. If you want to measure a different voltage, stop the simulation, adjust the source, and restart the simulation. This example will read a voltage of 9.0V.
DVM Series:
Ramp type https://everycircuit.com/circuit/4592385207304192
Dual slope integrating type https://everycircuit.com/circuit/6675184624599040
Integrating type (voltage to frequency) https://everycircuit.com/circuit/6172260362354688
Ramp Type (negative volts) https://everycircuit.com/circuit/5763215168110592
Ramp Type (auto ranging) https://everycircuit.com/circuit/6110164975091712
Counter Type ADC https://everycircuit.com/circuit/4509930926899200
Tracking Type ADC https://everycircuit.com/circuit/6418942605918208
Tracking Type ADC Full Version https://everycircuit.com/circuit/4688147021299712
Flash Type ADC https://everycircuit.com/circuit/4806466994962432
Pipeline Type ADC https://everycircuit.com/circuit/5739735974412288
Pipeline Type ADC 2 Bit Stages
https://everycircuit.com/circuit/6081127019970560
GENERAL:
Basically, I combined a 7 bit successive approximation register (SAR) and circuitry through a data serial stream to 2 cascaded Double-Dabble circuits. The SAR (left side of circuit) finds the binary number closest to the unknown voltage, and the Double-Dabble circuits (right side) convert this to decimal for the 7-segment displays
If you wish to get info on more details, I refer you to my hexadecimal version of this circuit
https://everycircuit.com/circuit/6044286526947328
and my Double-Dabble algorithm circuits
https://everycircuit.com/circuit/6548980953251840 and
https://everycircuit.com/circuit/6747473873469440
If you'd like more, an internet search for these topics will be helpful.
Marked waveforms:
Blue waveform: Clock for SAR
Green waveform: approximation voltage
Orange waveform: Input voltage
Red waveform: Serial data of the output of SAR
Other waveforms of interest:
Clock for the two Double-Dabble circuits (set to pulse 7 times for the 7 bit SAR).
Output of lower right AND gate.
Reset signal for the Double-Dabble circuits:
Logic source below counters.
Reset signals for the SAR:
Output of 3 lowest logic sources on the left.
Compare signal result for SAR:
Output of opamp.
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