Powerbank, output voltage, step-down converter


I want to use this powerbank :"VOLTCRAFT LiPo 30000 mAh" for my project which includes various sensors. My main goal is a stable voltage supply of 5V.

Now my question would be, if there would be any gain in stability of the 5V by using a step down converter, and make use of the ability of the powerbank to output higher voltages?

If so, how does the powerbank "decide" which voltage should be output

Many thanks in advance

it's already supposed to be a regulated output suitable for powering USB devices. might not be a perfect 5V though

If so, how does the powerbank "decide" which voltage should be output

that's up to the device's USB C port to use the "protocol" for indicating the required power from the source.

if you want a good source of current, you could use one of those adaptor

in between the powerbank and your gig. You'll get 5V and 1.5A available instead of the default 500mA

1 Like

Ok, but, as a secondary goal, how important is battery life?

The cells in the powerbank will likely be 3.7V li-ion, and they may be wired in parallel with a step-up/boost converter to output 5V, 12V etc. That boost converter will not be 100% efficient, probably 80%~95%. If you then use a step-down/buck converter, that too will be only 80%~95% efficient, so overall, the combination of converters could be only 65%~90% efficient, and waste up to a third of the powerbank's capacity.

1 Like