Tag Archives: voltmeter

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 can load your own code into this module but it has even some nice features for people who just need a voltmeter module and don’t want to play with C-code.

Programmable 8-character LCD module and digital voltmeter – [Link]

Variable Range LED Voltmeter


This is a variable range LED bar graph voltmeter project. It is a simple and less expensive project that displays voltage of a given source with the help of 10 LED’s. The project is based on the famous LM3914 IC from Texas instruments.

Variable Range LED Voltmeter – [Link]

Voltmeter clock project


Here’s a voltmeter clock project based on a multimeter clock design by Alan Parekh:

I have used three voltmeters and mounted them on a wooden plinth with a clear Perspex cover to give the clock an industrial look.
I have modified Alan’s code to run on PICBasic Pro version 3. I have also added the following.
Switched display On and Off (keeping battery backup as per Alan’s design) but also allows me to turn meters Off in full power mode.
Synchronization to my Master Clock every 30 seconds
Synchronized LED & Re-Synch LED
Synchronization On & Off
Transistor meter drivers
Separate hourly Chime Circuit
Pulsed “tick tock

Auto-ranging Analog Voltmeter for a variable power supply

w2aew @ youtube.com writes:

This video describes and demonstrates a fun little circuit that is designed to create a automatically switching, dual-range analog voltmeter which is intended to be built into a variable power supply. By using two ranges, it permits accurately setting a low voltage such as 3.3 or 5V, as well as accurately setting a higher voltage like 24V. Setting a low voltage using a high voltage meter is not very precise, hence the reason I put this together. The circuit is demonstrated, and the schematic is reviewed to describe the operation.

Of course, there are many ways this can be done – this is just one example. It uses one of my favorite little analog ICs, the LM10 op amp and reference. The LM10 (designed by the legendary Bob Widlar) is used as a voltage reference and comparator with hysteresis. A zener diode is used as a shunt regulator. There’s an indicator LED to show when the meter is in the high range, and a 2N7000 enhancement mode n-channel MOSFET is used to change the resistors associated with the analog meter.

Auto-ranging Analog Voltmeter for a variable power supply – [Link]

Voltmeter using arduino



voltmeter-using-arduinoby praveen:

This article is about a simple 3 digit voltmeter using arduino. The circuit can measure anything between 0 to 5V at an accuracy of 50mV. The circuit uses minimum number of external components and can be easily modified for different voltage ranges. The display device is a common anode multiplexed seven segment LED display module (Type No:E1-3056ASR1). Let’s have a look at the display device first.

Voltmeter using arduino – [Link]

Hacking a cheap LED voltmeter


ba0sh1.com reverse engineered a cheap LED voltmeter he bought from Taobao and made it run on a I2C bus. He writes:

I’m planning to build a EEVblog-ish constant dummy load for battery and power supply testing. Dave in his build used a LCD voltmeter for the display. In the senseless pursuit of difference, I tried other display solutions including character LCD, graphics LCD, OLED, TFT, AMOLED, IPS, which resulted in several previous blogs but nothing ends up to be satisfactory. Along with the complexity grows exponentially from one solution to another, I slowly start to feel the importance of KISS concept, keep it simple stupid. All I need is just a number display, nothing fancy, nothing pricey, nothing takes my attention away from the analog circuitry. I decided to go back to the basic 7-segment LED display. “Simplicity is the ultimate sophistication

Digital voltmeter using ICL7107


john @ circuitstoday.com writes:

The circuit given here is of a very useful and accurate digital voltmeter with LED display using the ICL7107 from Intersil. The ICL7107 is a high performance, low power, 3.5 digit analog to digital converter. The IC includes internal circuitry for seven segment decoders, display drivers, reference voltage source and a clock. The power dissipation is less than 10mW and the display stability is very high.

Digital voltmeter using ICL7107 – [Link]

Secret Arduino Voltmeter – Measure Battery Voltage

A little known feature of Arduinos and many other AVR chips is the ability to measure the internal 1.1 volt reference. This feature can be exploited to improve the accuracy of the Arduino function – analogRead() when using the default analog reference. It can also be used to measure the Vcc supplied to the AVR chip, which provides a means of monitoring battery voltage without using a precious analog pin to do so.

Secret Arduino Voltmeter – Measure Battery Voltage – [Link]

i-voltmeter – Voltmeter with Bluetooth Technology


The i-voltmeter is an electronic testing tool that can:

  • Diagnose electronic functions of anything you need to test
  • Data log electronic events over time
  • Remote view events with your smart phone
  • Create Remote Triggers
  • Set Alarms
  • Use as an anti-theft device
  • Measure electrical voltage, current & resistance

Now you can test a full spectrum of electronics with the diagnosis and data logging features of the iV. Other units cost upwards to $1000. Because it is Bluetooth enabled, you can unleash yourself from the testing device with the iV.

i-voltmeter – Voltmeter with Bluetooth Technology – [Link]