Cheap power bank with interesting circuitry.
Added 2019-05-23 19:45:20 +0000 UTCI got this in full expectation that the stated capacity of 2600mAh was a load of crap, which it is.
https://www.youtube.com/watch?v=3GXdXsIJPGs
On a plus note it has the simplest power bank circuitry I've seen with low quiescent current of only 11uA.
The downside of that is that the unit goes to sleep if the connected load is too low. It also glitches the output every second or so to see if a charger has been connected.
Comments
If it's the same type the output has to dip regularly so the chip can detect if an external power supply is present for recharging. A capacitor may result in odd behaviour.
Big Clive
2019-05-29 23:16:55 +0000 UTCI bought a couple of these chargers for 2 cells. They were sold for les than 1 Euro, without cells. I put in some Samsung Q30 cells to power some copper kable LED strings and they performance fine. The only problem is that they flicker once after every 10-20 seconds. If you regulate the current down with a resistance, the time between a flicker increases. Could a capacitor across the output reduce that effect?
Hub Rijcks
2019-05-28 21:38:50 +0000 UTCClive, these power banks are very interesting. They don't put all the cells in parallel, you get charge status for each cell and they seem to have reverse insertion protection/indication too. https://item.taobao.com/item.htm?spm=a1z09.2.0.0.2f5d2e8d7fHa5n&id=548790320889&_u=s1sfp74r0c99
2019-05-28 14:33:15 +0000 UTCTechnically speaking this device would do that since it has the in and out connectors paralleled together. I'm not sure if it would kick in instantly though.
Big Clive
2019-05-27 05:05:24 +0000 UTCI'd be interested to know whether you've come across any of these USB power banks that have what they seem to call a "UPS function", in that you can connect them to both a charger and a device at the same time, and they'll run the device off the charger and keep the battery topped up, but the moment the charger goes away they'll start supplying 5V with little to no interruption in the output, switching back with again no interruption once the charging current returns. I think these would be very useful to keep some 5V things like security cameras running uninterrupted through short power outages, but it's surprisingly difficult to find out whether a device has this functionality or not without actually testing it.
Berkeloid
2019-05-26 23:20:31 +0000 UTCI've just checked, it's 40mA.
Big Clive
2019-05-24 05:00:32 +0000 UTCPurple is just navy pink!
mikenco
2019-05-23 22:44:56 +0000 UTCAre you sure purple isn't just pink with blue impurities?
Scott Miller
2019-05-23 21:45:48 +0000 UTCPink is just a degenerate form of purple. Everybody knows that.
Mark Trombley
2019-05-23 20:23:18 +0000 UTC
