LM3914 meter for 25 V DC
“I wish to assemble a bargraph display to indicate approximately 25volts dc.How many LM3914 I should cascade? How to calculate resistor value which is grounded from the junction of Pin 6 & 7 (Rhi...
Category: Test-Measurement
ICL7129 AD Converter needs Triplexed LCD
I’m using the ICL7129ACPL to construct a simple 4-1/2 digit DVM. I looked over the application notes on FE LCDs on a similar post and noticed that it listed the FE0206 4-1/2 digit LCD...
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 ranges by changing the constant current in decade steps....
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 when you want to measure Volts, Amps, Ohms and...
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 not broken if the shunt blows. The Ammeter is...
