On Thu, Oct 13, 2016 at 6:05 AM, Van Horn, David <david.vanh...@backcountryaccess.com> wrote: > To be fair here, phone chargers have almost no requirement to be quiet other > than conducted and radiated emissions limits. > It's charging a battery.
Not only that but, the 5 volts comping out of the larger is almost certainly the input to another DC/DC power supply and NOT used directly. You can't charge a Lithium battery with the 5 volts the charger outputs. If you don't know about LiPo batteries, they need a constant current power source and then as they get close to charged the charger switches to constant voltage (VERY roughly) at about 4V per cell. I have a project right here on my desk as I type. I'm using the output of a generic USB hub. The circuit is a cap from 5V to GND and then a low dropout regulator to get 3.3 volts. I don't care to much if there is huge ripple on the 5.0 volts coming in as long as it stays above the LDO limit. Also it looks like they tested the USB chargers with no load. A typical load might have a say, 0.01uf cap to short the noise to ground. So in use the power might be better? It was no surprise the counterfeit chargers were horrible. The manufacturers are by definition of "counterfeit" being dishonest slim balls. Why would he care about anything other then that he can fool some people into buying his product. There are third party chargers that are not trying to copy a well known brand, these are usually much better -- Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
