Can multimeters be powered by DC-DC buck converters?

[SteveLTN]

I have a few Lithium AA/AAA batteries which have USB-C ports and can be charged directly.

They always produce flat 1.5V until they die suddenly. I'm pretty sure they use Buck converters inside to step-down from Lithium cell's voltage to 1.5V.

I like them fairly well because a lot of devices have fairly high shut-down voltage which makes Ni-Mh batteries not very suitable. But these Lithium ones are compatible with these devices very well. Of course one problem is that you can't estimate the battery life. But with easy USB-C charging, I'm not super bothered by this.

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The question is, can I use these batteries in multimeters?

Using buck converters mean they don't produce stable 1.5V. They must have ripple voltage. While it doesn't matter for most of my appliances, I'm unsure it they are suitable for multimeters.

Can multimeters deal with that? Or would it cause any long-term inaccuracy or damage to the meters? I did do a simple test, it seems fine. Just want to confirm from a theoretical and long term point of view. Thanks!


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PS.
I have a 9V USB-C chargeable Lithium as well. It's basically two 3.7V Lithium cell in series, so no ripple. The voltage is a bit low, but it works just fine in my multimeter.
Plz be aware that some 9V USB-C batteries use boost. You need to be careful when purchasing.

[Andree Henkel]

long term inacurracy: unlikely - as soon as you change back to origiginal supply any inaccuracy caused by ripple should vanish

damage: unlikely

however you can probably get measurement errors, the ripple can get converted to DC or AC measurement Errors in measurement electronics of the meter

so basically is still not a good idea, at least if accuracy is of concern

[SteveLTN]

however you can probably get measurement errors, the ripple can get converted to DC or AC measurement Errors in measurement electronics of the meter

so basically is still not a good idea, at least if accuracy is of concern

I guess the linear regulators won't have ripple-removal circuit built-in then. Makes sense because they are designed to use normal batteries which are really clean source. Good to know!

[tszaboo]

I've replaced my 9V batteries with lithium ones with DC-DC inside. They measure voltage.