Circuit Lake

Electronic Project and Circuit Collection

AVR Inductance Meter

02/19/2011 Category: AVR, Digital, Measurement, Microcontroller, PIC, Project

This Inductance Meter project is built based on AVR ATmega48V. Its firmware was written in Basic and compiled using Bascom AVR. The project use laptop or PC USB to supply the 5V power.

To find unknown inductance (Lx), this L meter uses formula below and then display the result to 16×2 LCD.

math formula to find inductance value

The code solves for inductance (Lx) using 2 known values: capacitance (C) and frequency (f). The capacitance is set using a 1nF capacitor and the frequency is generated using the comparator. Once the meter is calibrated then the second formula can be used to determine the change in inductance when an inductor is placed across the probes.

L meter with Bascom AVR

“With minor modifications the meter could also be used to measure capacitance”, said H. Williams, the designer. Download schematic and source code (bas).