# Circuit for a UPS **URL:** \ **Category:** Uncategorized\ **Created:** [15 December 2019 06:06 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995 "2019-12-15T06:06:07Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Kevin48023](https://avatars.discourse-cdn.com/v4/letter/k/c0e974/32.png) [@Kevin48023](https://forum.core-electronics.com.au/u/Kevin48023)\ **Post date:** [15 December 2019 06:06 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995/1 "2019-12-15T06:06:07Z")
I am looking for a circuit for a UPS based on one or more 18650 batteries. The UPS must be capable of delivering 5V at, say, 500mA for, say, 30 minutes. Yeah, specs are a little hazy - and subject to change at my whim and fancy. 😉 What are people using? Off-the-shelf or custom made? Links? Yes, I’ve Google’d but haven’t found anything useful. tia ---
**Author:** ![Bryce](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/bryce/32/3631_2.png) [@Bryce](https://forum.core-electronics.com.au/u/Bryce)\ **Post date:** [18 December 2019 03:56 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995/2 "2019-12-18T03:56:59Z")
Hey Tia, If you’re looking for a power bank/UPS for 5V or USB devices I’d recommend a [Pi Juice](https://core-electronics.com.au/pijuice-zero-a-portable-power-platform-for-raspberry-pi-zero.html) setup as it can act as a standalone battery pack, solar or UPS-like power storage system. All the best with your projects! Bryce Core Electronics | Customer Support ---
**Author:** ![Kevin48023](https://avatars.discourse-cdn.com/v4/letter/k/c0e974/32.png) [@Kevin48023](https://forum.core-electronics.com.au/u/Kevin48023)\ **Post date:** [18 December 2019 04:13 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995/3 "2019-12-18T04:13:42Z")
Thx for the reply but the Pi Juice is well beyond my budget. ☹ BTW: tia := Thanks In Advance 😉 Kevin ---
**Author:** ![Bryce](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/bryce/32/3631_2.png) [@Bryce](https://forum.core-electronics.com.au/u/Bryce)\ **Post date:** [18 December 2019 04:30 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995/4 "2019-12-18T04:30:22Z")
Hey Kevin, All good, what’s the nature of the project the pseudo-UPS is being used for? I may be able to help you find something more appropriate. Bryce ---
**Author:** ![Kevin48023](https://avatars.discourse-cdn.com/v4/letter/k/c0e974/32.png) [@Kevin48023](https://forum.core-electronics.com.au/u/Kevin48023)\ **Post date:** [18 December 2019 05:18 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995/5 "2019-12-18T05:18:53Z")
Anything from a Pi4 to just a simple board with a power requirement of, say, 100mA. Of course, that would probably mean two different devices given the power a Pi4 draws. For the low power case I’ve used one of these in the past: [https://www.ebay.com.au/itm/UPS-Step-Up-Power-Supply-18650-Battery-Charging-Board-Undervoltage-Protection/153696735155](https://www.ebay.com.au/itm/UPS-Step-Up-Power-Supply-18650-Battery-Charging-Board-Undervoltage-Protection/153696735155) ---
**Author:** ![Bryce](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/bryce/32/3631_2.png) [@Bryce](https://forum.core-electronics.com.au/u/Bryce)\ **Post date:** [20 December 2019 04:06 UTC](https://forum.core-electronics.com.au/t/circuit-for-a-ups/6995/6 "2019-12-20T04:06:04Z")
Hey Kevin, I’d just go with a standard battery pack or a LiPo/NiMh battery pack with the 5V output you require. You can power a Pi 4 directly from the GPIO so you shouldn’t need more than one battery pack as if it has enough capacity you can simply run both devices in parallel using a splitter or a similar split connection. All the best with your project!