Build a DMM – LM3914 Analog display
2020-12-31
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 the measurement aspects and theRead More
AC conversion and Continuity – DMM
2020-12-31
U1A LF353 opamp turns on a buzzer when the voltage at Test + falls very low indicating a short between Test + and Test – or a resistor less thanRead More
Voltmeter Attenuator Rectifier
2020-09-19
Measurement of Voltage : – In testing electronic circuits, Measurement of voltages is important for diagnosing faults and making the circuits work. In circuit diagrams given in equipment manuals, voltagesRead More
Voltage Attenuator Amp – DMM Project
2019-10-28
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 will take upto 500V. UseRead More
Analog and Digital Voltmeter using ICL7107
2019-06-11
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 in the 200mV configuration. U4ARead More
Resistance measurement with Current Source – DMM
2015-04-23
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 ranges by changing the constantRead More
Analog Buffer and Inverter Switching – DMM Project
2015-04-20
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 when you want to measureRead More
Current Amp digital control – DMM Project
2015-03-30
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 not broken if the shuntRead More