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Fixed out of range errors and stabilized least significant bit. These were the problems in my last version. Believe me, this was a lot harder to solve than I thought! This digital volt meter (DVM), with tracking Analog to Digital Converter (ADC), can read a voltage up to around 10V with an accuracy of about 100mV. It is currently set to read 2V.
DVM Series:
Ramp Type https://everycircuit.com/circuit/4592385207304192
Dual Slope Integrating Type https://everycircuit.com/circuit/6675184624599040
Integrator Type (voltage to frequency) https://everycircuit.com/circuit/6172260362354688
Successive Approximation Type (hex) https://everycircuit.com/circuit/6044286526947328
Successive Approximation Type (decimal)
https://everycircuit.com/circuit/5334865438048256
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
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
INSTRUCTIONS:
The voltage source on the left is the unknown. The 7-segment displays in the right show the result. The number on the displays should count to the correct amount and stay there.
GENERAL:
Please check out my last circuit if you'd like to know the basics of a tracking ADC. https://everycircuit.com/circuit/6418942605918208. This design is the same, with some improvements listed below.
Blue waveform: Tracking Voltage.
Green waveform: Next operation clock.
Orange waveform: Latch digital number signal
Red waveform: Load operation clock.
DETAILS:
Two more checks are added to handle the '00' case and the '99' case (center logic gates).
If the 00 case is encountered, the logic forces an increment. The display will oscillate around 00 and 01
If the 99 case is encountered, the logic forces a decrement. The display will oscillate around 99 and 98.
To remove the fluctuations in the LSB, the output digital number must be latched when it changes by more than 2. Two extra counters are used as the buffer latches. A state machine is used to determine when to load the buffers with the digital number (top right flip-flops and logic gates). This wasn't an easy task!
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