A general question..looking for the best route to solve it. USB/5V powerbanks are a great idea for charging cellphones or running medium wattage LED's while camping etc. However, there seems to be a minimum output load required, else they shut off after approx 15 seconds. The one i'm struggling with, uses a TP4333 (functionally very similar to the common TP4056 and clones), which can charge an 18650 battery well to 4.2V and also handle up to 800mA output too. 1 chip + an inductor and a couple of LED's, caps and resistors. Elegant, in it's own Chinese way. I bought 5 'kits', with the circuit, battery contacts and plastic cases. https://www.ebay.com/itm/H1-Portable-Power-Bank-USB-18650-External-Backup-Battery-with-Charger-Key-Chai/282434770730But, the whole problem is that the devices i'm trying to power don't draw enough current ! If you plug say an Arduino into a chargebank, it will run for a few seconds and then everything turns off. Minimums appear to be around 65mA, though that is just a regularly written figure on various websites and videos. Here's the only datasheet I could find: http://www.wendangku.net/doc/f3cc639e48d7c1c709a145a4.htmlIt's either a lot newer than the TP4056 or just not as often used. Have tried connecting Pin 5 (SWT) to Ground and the circuit did fire up, but went off again a few seconds later, even if the 10K resistor was still in place. I'd perhaps be best to put a switch and a resistor across the output rails for around 50mA short circuit type of load, then the actual load would send it above its switch off minimum. Is there a workaround ? it seems very wasteful and the batt won't run the device as long as it could.
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