Third Party > Repairing and Upgrading Rockbox Capable Players

bricked H320 (works as a flashlight now): help please?

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ej0rge:
if the charge controller includes a 'charge pump' type of circuit to boost the voltage it's receiving, having too low of a voltage would certainly make it work harder.

But i don't think there is any reason why more than 5.0 volts would be needed to charge a 3.7v lithium pack. Maybe I'm wrong on that point.

As for chargers with a lower amperage rating, it's possible that they simply meant to use a charger with an unusually high rating vs. the required charge current for the battery + everything needed to run the DAP simply to avoid getting an ugly jaggy waveform from the power supply under load.

Aside from their obvious capacitance and voltage tolerance ratings, capacitors are also rated for what frequency of repeated pulse they can service and how many miliamps can be drawn from the capacitor between each pulse. A badly jaggy power supply would certainly make the capacitors work much harder.

But we're talking - we hope - about voltage regulated chargers here. A linear regulated 5v 2a brick would weigh a couple pounds, so we're talking about a switching regulated power supply. Some of these are going to switch at much faster rates than others.

If i let the battery drain to the point of exhaustion and then hooked up an ammeter between the power brick and the h320, and then fired up something heavily cpu intensive like a video speed benchmark or a database rebuild, i doubt we'd see the h320 draw more than 4/5ths of an amp - and I'm being generous.

But better quality of the power it receives is more easily achieved by using a higher current rated supply than by using a lower rated but more aggressively regulated supply.

damasta:
gentlemen, i appreciate your feedback!

the charger i was using - while not original, complied to the same specs: 5V 2A. it is the original charger for my tomtom go700 automobile satnav system. i assumed that both devices would have similar demands on the PSU in terms of noise, hum, transient behavior etc...

well, i finally managed to grab a "new" h320 off ebay for 105,00 €! fourth attempt tho... i am surprised to see other h320s go for 150+ €, which is about half the original price! amazing. these are 3-5 year old devices and in this day and age of "throw away" personal electronics, i am impressed. seems to be becoming something of a collectors' item...

i guess it just confirms that iriver really landed a major milestone at the time, which even today is hard to top.
from personal experience i can say that after surfing for an alternative to the h3x0 series, still nothing else comes close to what i need from a personal mediaplayer...

thanks again guys!

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