> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt # Power Bank KeepAlive (Adjustable) **Type:** Product page · **SKU:** TPH-106339 · **Brand:** [The Pi Hut](https://core-electronics.com.au/brands/the-pi-hut) **Page:** https://core-electronics.com.au/adjustable-usb-power-bank-keepalive-device.html ([markdown](https://core-electronics.com.au/adjustable-usb-power-bank-keepalive-device.html.md)) Most power banks will automatically turn off their USB ports when the power/current being drawn is lower than a certain value. This makes it impossible to... ## Pricing - **Price:** $18.50 (inc GST) — $16.82 AUD, exc GST - **Quantity discounts:** 10+ $16.15 (exc GST) · 25+ $15.64 (exc GST) ## Availability & dispatch - In stock, ships same business day if ordered before 2PM (Australia/Sydney). - We can dispatch 13 today, and up to 500 more in 5–8 days. ## How to buy - **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=TPH-106339:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart. - **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/TPH-106339:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.) - **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there. - **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works) - **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt ## Description Most power banks will automatically turn off their USB ports when the power/current being drawn is lower than a certain value. This makes it impossible to run low-power devices on a power bank, such as a [Raspberry Pi Pico](https://core-electronics.com.au/raspberry-pi/microcontrollers.html), small [microcontrollers](https://core-electronics.com.au/collections/adafruit-development-boards) or even charge your AirPods. **...until now!** This is a **USB KeepAlive (adjustable version)** which does exactly that - it keeps your power bank 'alive' by pulsing a small amount of current (via a 555 timer - *neat*) through the USB port. The pulse combined with the keepalive's low-current draw from your end device will keep your power bank alive. This **adjustable version**has a very similar circuit to the assembled KeepAlive, however **comes with the ability to adjust the strength of the pulse** using the slide switch to three different set values. Whilst the standard assembled version has a resistor value that works for most projects and power banks, some of our customers asked for the ability to change the value easily, to cater for some awkward power banks*and*to potentially allow an even lower pulse power consumption. Plug one end of this into your power bank and the other end into your device, and there you have it - an easy, reliable mobile power source with an adjustable pulse! How does it work? The Keepalive works by periodically sending a small electrical pulse which, when combined with another device plugged into it drawing a small amount of power, is usually enough to keep a power bank from shutting down. By default, we would recommend you start on low and only try medium or high if your power bank does not stay powered on. Below are the approximate draws for each of the settings: - **Low**= 100mA - **Medium**= 145mA - **High**= 170mA Be aware that at **the highest setting, a small amount of heat will be generated** -**please ensure that you do not cover the unit** with fabric or similar and air is allowed to flow around the device when in use. ### Use cases Whilst we originally stocked the range of keepalives for small dev board purposes, there have been many interesting use cases that customers have shared with us. It's great to hear about the weird and wonderful places our keepalives are used! - Charging Hearing Aids - Charging earbuds - Timelapse photography - Running a mobile Raspberry Pi Pico/microcontroller ### Resources - [Documentation](https://docs.eplop.co.uk/USBKeepAliveADJ) ### FAQ - **Will it work with my power bank?** - As you may appreciate there are *thousands* of power banks out there which means it's impossible to be able to test and verify with every power bank. We have chosen a middle ground regarding how much power the device draws to balance out keeping a power bank alive while not affecting battery life too much. - **Can it keep a power bank alive on its own?** - No. The keepalive device is designed to work in conjunction with another small power source. - **Can it work with power delivery / QC** - No. The keepalive is only designed to work at 5v and so can only keep alive 5v devices. If you try to plug it into a PD power supply you risk damaging the keepalive and other hardware. ### Package Contents - 1x Power Bank KeepAlive (Adjustable) ## Images - [Product image 1](https://core-electronics.com.au/media/catalog/product/T/P/TPH-106339-1.jpg)