Voltage Attenuator Amp – DMM Project
LF356 opamp FET input is in a inverting amplifier configuration here. R4 + R5 make up Ri each 1/4 W MFR withstands 250V so both […]
DMM-Project
Analog and Digital Voltmeter using ICL7107
This Circuit is a DPM or digital panel meter. It has a analog bar graph display and a 3-1/2 digit digital display. ICL7107 is used […]
Resistance measurement with Current Source – DMM
U3 LF 356 is used as a constant current source (sink as the current is negative). R4, R5, R7 and R9 set the four resistance […]
Analog Buffer and Inverter Switching – DMM Project
Here the 4053 selects or routes the voltage, current or resistance measurements to the A-D converter or display. It is selected with the mode selection […]
Current Amp digital control – DMM Project
R6 is the Shunt thru which the current to be measured passes. F1 fuse is to protect shunt. D1-D4 ensures that the current flow is […]
DMM range and AC-DC mode Logic
This is the third circuit that you will need to build a Simple Benchtop DMM with no Microcontroller. Here the U1D and U1B 4093 acts […]
Power supply with battery backup – DMM
This is a simple charger circuit which will work for a light load like a DMM, the Battery can be a sealed maintenance free battery […]
Build a DMM – LM3914 Analog display
This a part of a complete Benchtop DMM that you can build to learn the internals of a Digital MultiMeter. This is oriented towards learning […]