I want to use pololu step-up converter https://www.pololu.com/product/2836 in order to power a 5V device with two Ni-Mh batteries (1.3V each). It has only Vin, Vout and GND connectors. I've checked with voltmeter the batteries together and they give stable 2.6V, which should be, according to specs of the converter, enough to make it work.

I've tried wiring as below

Wiring I've tried
but the voltmeter shows 0.48V, when I'm expecting 5V...

I don't know what am I doing wrong... Is this wiring wrong or my converter broken?

  • 2
    \$\begingroup\$ Just took a quick look at your link and it says this, pretty prominently:(Note: it requires an input voltage of at least 3 V to start, but it can operate down to 2 V after startup.) \$\endgroup\$ – John D Jul 7 '18 at 18:14
  • \$\begingroup\$ If you want exactly this 2x Ni-Mh setup, this is probably not the best regulator available, you'd be better off with a step-up only converter, like this one. \$\endgroup\$ – anrieff Jul 7 '18 at 18:18

Solution found: My input voltage was too low to start the module... I'm not sure how I've missed it, but replacing Ni-Mhs with regular alkaline batteries ~3V total made this circuit behave as expected... Thank you, John D for pointing that out.

  • \$\begingroup\$ That might not be a good long-term solution since the voltage on the alkaline batteries will drop with use and at some point the circuit will not start even though there's plenty of usable energy left in the batteries. \$\endgroup\$ – John D Jul 7 '18 at 19:38
  • \$\begingroup\$ But what if I use 3x Ni-Mhs instead of two? Wouldn't that be better? \$\endgroup\$ – jacob m Jul 7 '18 at 21:36

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