https://stream.echo6.co/videos/watch/ab79edaf-21b5-4c0d-8cb3-9c89d643e392 This little module is based on the classic USB boost converters that can supply various voltages, but in this case with the addition of a charge current monitor for charging status display. When i saw the LM358 dual op-amp I considered that it might be for current feedback to the boost chip, but sadly it's just for the charge status LEDs and the current regulation relies entirely on whatever the chip can handle when running at full tilt, as it will not receive any feedback signal until the battery is charged and the internal protection circuitry found on these jack-charged clones, ends the charge. Not sure what the reliability of these units will be, as they are pushing the little chip hard for potentially several hours at a time, and it gets hot fast. They could have added just a few components to the circuitry to lower the charge current in a controlled manner by providing feedback to the boost chip. They could even have used one of the op-amps for that purpose to keep the value of the sense resistor low. While these are novel and have their uses, I don't totally recommend them. But if you want to play around with one, then here's a link to the item on AliExpress (not a sponsor). This is an affiliate link, but that will not affect the price you pay. If you view this item or add it to your cart it may appear in the bundle deal section. https://s.click.aliexpress.com/e/_c3e3na0n Guide price around £1.50 With suitable resistor tweaking these can also be used as fixed voltage boosters for other uses. Supporting the channel with a dollar or two on Patreon helps keep it independent of YouTube's quirks, avoids intrusive mid-video adverts, gives early access, bonus footage and regular quiet Patreon live streams. https://www.patreon.com/bigclive Alternatively, for a single coffee contribution you can use PayPal:- https://www.paypal.com/paypalme/bigclive #ElectronicsCreators Wed, 15 Apr 2026 09:56:02 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/ab79edaf-21b5-4c0d-8cb3-9c89d643e392 All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.