Measure sleep current uA/nA of battery equipment using a cheap meter.

Measure tiny nanoAmp currents with a cheap digital meter when your microprocessor sleeps, even if your meter can't natively measure that low. I show my prototype board, then the finished project.
0.00 What's in this video?
0:20 The need to measure tiny currents
1:02 Basics of current measurement
1:41 Shunts - using a voltmeter to measure current
2:30 Why you shouldn't trust your meter
3:41 Table of shunt values
4:12 Resolution of meters
4:35 How to fix wake-up problems
5:16 Full schematic
5:34 First prototype
5:53 Final version - adding a ground socket
6:06 How to use the Nano-Amper
7:20 Profiling current with a 'scope
7:55 Limitations
8:36 Why you should build it

[@Leezorc]

Simple and cheap, I like it.

[@richardlangner]

Thanks for the kind comment. A friend wanted to measure the sleep current of his car after various sections shut down gradually, and this would be an ideal way to do it. Just replace the relevant fuse with a blown one (so you can connect wires to it) and put the diode/resistor/meter across it (and a fuse in series for extra protection of course).

[@GarryHeard]

I found your site by chance. You have some great videos and ideas! Please keep up the good work. I love the short videos that I actually have time to watch.

[@richardlangner]

Thanks for the nice comments, I know that people like short and 'straight to the point' videos, so I try and impart as much as I can in as little time as I can!

[@MuellerNick]

A simple and effective solution. Thanks for the inspiration!

[@janeklof2769]

Many thousand thanks for your interesting and useful video on measuring very low currents. Greetings from a cold Stockholm and Jan Eklöf

[@richardlangner]

Hi Jan, thanks for the reply, I'm glad it helped you understand how to use existing equipment and extend its use for virtually no money.
Richard,

[@garymucher4082]

As usual, when the need to measure things and typical DVMs are not setup to do that, you improvise and built whatever it takes to get the reading. Thumbs Up!

[@richardlangner]

Thanks for the comment. I like to showcase ideas that I've used, and that aren't shown elsewhere.

[@zdravkopavic8469]

I used the same Priciple tp measure high resistors.
Simply a voltage source in series and then measure Voltage.
Ohms law for the rest.
I love electronics.

[@richardlangner]

Yes exactly the same principle. Way back I used it to mearure 100Mohm resistors; 240v ac across the 10M meter and 100M resistor in series gives about 22v ac. Glad you liked the video.

[@grahamdriver7534]

Very nice, though I do prefer to see current going left to right. Picky? Me?

[@williamlucid8907]

Thanks for the content of this video. Is there a disavantage to not using smt resistors? Woulld wattage resistors did you use?

[@richardlangner]

You can use any type of resistor. The wattage is very low so okay to use 1/8W resistors for all but the 1mA range which should be 1/4W.