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I've been using the Atmel Power Debugger to sort out power consumption issues on some µController based circuits... and have been pretty pleased. Unfortunately, it's limited to a maximum of 5.5 volts and I need to work on some circuits which are a little above that range, up to 18 V.

Can someone recommend a method and or off the shelf hardware to help me get going on DC power measurements in the 0-18 V range?

What are some options for logging power consumption over several hours... maybe as long as 24 hours to evaluate circuit / firmware performance?

A different post (How to Measure Power Consumption on Extremely Low Power Devices?) mentioned the µCurrent Gold Multimeter adapter to utilize with a multimeter, but it's out of stock.

Any suggestions would be greatly appreciated!

Greenonline
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  • Providing you don't want to measure sleep state current below about 100uA you could use a INA219 and Arduino to log power usage. – Jack Creasey Oct 23 '18 at 05:59
  • A few years ago I had a [similar issue](https://gr33nonline.wordpress.com/2015/08/03/choosing-which-multimeter-to-buy/), and I plumped for the Uni-T UT71D - cheap (considering what it offers) and has data logging. EEVBlog also recommended it. – Greenonline Oct 23 '18 at 06:54
  • I do not know what current range you are in, but perhaps the VA mode on the EEVblog 121GW? – Jeroen3 Oct 23 '18 at 07:20
  • Labjack is a decent low-cost and easy-to-use data acquisition system. You would need to add a current sensor of some sort (like the INA169 breakout board). In addition, you would need a resistor divider for the voltage to bring it down within range of the labjack ADC input. You can place the divider so that the divider current does not flow through the shunt. Log all data to a PC. – user57037 Oct 23 '18 at 07:31
  • On any of these shunt-based current measurement devices (such as INA219 and INA169) you can increase the shunt resistor value to increase sensitivity. You only run into problems if the current varies over a wide range. Larger shunt means larger voltage drop. – user57037 Oct 23 '18 at 07:33
  • @mkeith Unfortunately you can't just increase the sense resistor and get every lower current sensing capability for the INA series. The input bias current can over 20uA, so even 100uA with any real accuracy is a challenge without buffering the input sensing. – Jack Creasey Oct 23 '18 at 16:03
  • @JackCreasey, I will admit I didn't even look at that. My bad. Maybe a diff-amp then built from precision op-amps. – user57037 Oct 23 '18 at 16:06

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