App note: Signals with zero offsets

Dealing with zero offsets signals tackled in this app note from Murata. Link here (PDF) Many transducer outputs exhibit a dc offset voltage when the output level would normally be expected to be zero Volts (corresponding to a display reading of “000”). As an example, consider a pressure transducer whose output levels of 1.0Vdc to […]

Programmable 8-character LCD module and digital voltmeter

A programmable 8-character LCD module and digital voltmeter project from Tuxgraphics: Our 3 digit LED digital voltmeter module has been quite successful over the years. This new LCD module is basically an advanced version with a lot more capabilities. You can power it with the same voltage source that your signal is derived from. You […]

I2C LED Display from Hacked Voltmeter

Tom writes: I turned up this cool project write up that reprogrammed a cheap LED voltmeter for use as a general purpose 7 segment display with I2C communication. These voltmeters cost about $3 instead of $10 for an equivalent LED display backpack from Adafruit. NB the author used a Bus Pirate to troubleshoot the bitbanged […]

Digital clock from an old nixie tube multimeter

James built a digital clock that displays the hours and minutes on an old Nixie tube multimeter. The multimeter functions as a voltmeter that is reading the output of an Arduino generated voltage. There are still some noise issues to clear up, but all in all it’s a cool looking clock. Check out the video […]

Voltage monitor for car’s battery and its charging system

Raj designed a car battery volt-meter. The core of the project is a PIC16F1827 which uses its internal fixed voltage reference FVR and ADC to precisely measure the battery voltage. Measured voltage is displayed on a 4 digit 7 segment display. His circuit is connected to the car’s battery through a standard car lighter jack. Via the […]