Most of the times, measurement in electronic circuits, our requirement is measuring DC voltage.  Normally, we will set the multi-meter to DC voltage mode and check the voltage levels at various points on the PCB.  Mostly, our requirement lies between 5V to 15V DC.  The circuit shown is simple, occupies less space and can directly connect to the DC voltage for measurement.  To minimize the size and power consumption, 8 pin MCU and 0.96” OLED is used in the circuit.

This is a project based on Arduino board which can measure the unknown AC and DC voltages. When we connect the unknown voltage on the breadboard circuit, the 16×2 LCD displays the voltage value. The project uses an Arduino pro mini board whose ADC feature is used along with the concept of Voltage Divider circuit to develop this Voltmeter.  

Digital equipments have rapidly replaced Analog equipments in the long run. Well that is because the former has lot of advantages over the latter. But do you miss those retro style analog measuring instruments? Those pointy indicators and graduated scales? Well I do and so have decided to build one with the “modern” parts. This article will show you how to make a Retro Style D.C. Voltmeter which can measure in range of 0-30V. 

In Electronic field voltmeters have found an essential place, Voltmeters are of two types AC &DC and here I have demonstrated a working AC Voltmeter. It has a large range from 0V to 1000V.The output is shown on 7 segment display.The main part of this project are :-  Converting Circuit(For converting Ac to dc in range of 0-5V), ADC Interfacing(10 bit Inbuilt ADC of 16F676), 7 Segment Multiplexing.I have used PIC 16f676 microcontroller in this circuit. It has bridge rectifier which is made from diodes In4007.It convert Ac Voltage to Dc Voltage. Next is Voltage divider circuit which converts any voltage from 0 to 1000v to 0 to 5v range. It is made using two resistors and a potential meter in series. Next capacitor is used for removing ripples .the zener 5.1V is used for protection it will never give voltage to controller more than 5.1 V.