Diode meter that can talk to PC

Hi,

I am totally new to arduino and would like to start a project. But I need to survey if it is feasible and wanted to understand the extent of its complexity of this project it will get if it could be done.

I am intended to build a diode tester as the one we have on Digital Multimeter (diode mode).

After the tester measure the stable reading, the reading will be saved and export to PC through USB cable anytime at user desired.

Ultimately the tester will be measure at least 300 reading and export altogether at once.

Would anyone advise if this project can built with arduino? Thank you.

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I would look at using the ADC to measure the voltage across the diode when fed with a highish value series R.

The forward V should be around .5 to .7v depending on type. LEDs will be up to 3.5v or so.

Weedpharma

That's a pretty good idea! The Arduino should be good for that.

Are you expecting this thing to be battery operated and portable or is it always tethered to the USB cable? Remember standard Arduino's are automatically reset when plugged in, so you need non-volatile storage for the data. The on board EEPROM can do this for up to 512 integer measurements. Any more than that an SD card is a good storage method.

Is that ADC for the display of its measurement value?

It would be battery operated and that wouldn't be any problem for it to be reset every time it get plugged in.

You use the ADC input to measure the voltage across the diode under test. This gives a number between 0 and 1023. This is then converted to a value of voltage by your program. This would need to be saved in a form that is not erased by turning the power off. This means using EEPROM or a SD card.

Normally all variables are lost by resetting your Arduino so you need to specifically save the data.

Weedpharma

Hi,
Why can't you test the diode with the PC connected?
The voltage drop can immediately be serially sent to the PC when the measurement is made or stored in volatile memory until it is needed to be uploaded.

No storage in controller required.

Tom.... :slight_smile:

What are you measuring the diode for?

Do you just want to confirm that the resistance in one direction is greater than the other?

You can have it automatically swap the connections on the diode by wiring a resistor to a digital pin then the terminals for the diode and finally back to another digital pin. Connect the terminal end of the resistor to an analogue input. Make one pin high and the other low and take a reading then swap them over and read again.