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nerys · 09-01-2007, 12:30 PM

HarryT it works fine. in fact its how I have been charging my reader for the past 6 months. I lost the AC charger a long time ago. My cord has a USB Plug on one end and a "psp" plug on the other end. Charges up just fine on the computer and on the "dumb" charges I have all over the place. I have AC and DC version (AC plug with a USB port on it and 12v plug with a USB port on it)

On a charger like this its impossible for it NOT to work as long as the voltage etc.. is correct. there are only 2 conductors no "signal" wire so there is no way for the reader to make a determination as to what is sending the juice. if its the right juice it just accepts it. ie the sony charger is a "dumb charger" it just puts out 5.2v +tip 1amp power.

How you derive that power is not relevant so long as its correctly formatted power.

On another note I just put a meter to all my USB ports and they do put out constant power regardless of whats plugged into them.

On further reading it seems to depend on the DEVICE circuitry. ie there are 2 ways to "charge" via USB it seems. you can shunt the positive and negative from the USB pin outs to the charging jack (ie dumb charge) in which case plugging it in will work on either the barrel plug or the mini a usb plug.

OR you can route the power through a separate circuit in the device. in this case THAT circuit will need to "turn on" to do its job. this is a case where it may be required to have the sony software (only for the miniA jack not the barrel jack) since that circuit may need "conditions" to turn on such as a valid computer connection.

This is possible in the case of the reader since when FULLY dead the USB port my not provide enough amps to charge the device (90% of them will) but to play it safe this extra circuit would be designed to not accept the voltage if the amps are too low to not risk damaging the Lithium cells.

Every dumb charger I have seen puts out over 1amp which is why they all work fine. Plus there going through the Barrel Plug.

NOW if you took a MINI A plug into that dumb charger into the reader it MIGHT not work - I have never tried. I will try it later on and let you all know. but if you use PSP USB plug (get the one with JUST the barrel plug some have the barrel and MINIA) it will work just fine from any DUMB usb charger.

Again BARREL plug should work fine (I use over a half dozen of them all work) USB JACK (ie the MINI A port on the Reader) that might not work.

Chris Taylor
http://www.nerys.com/

09-01-2007, 12:30 PM	#26
nerys Addict Posts: 243 Karma: 48 Join Date: Dec 2006 Device: PRS 500 - REB 1200	HarryT it works fine. in fact its how I have been charging my reader for the past 6 months. I lost the AC charger a long time ago. My cord has a USB Plug on one end and a "psp" plug on the other end. Charges up just fine on the computer and on the "dumb" charges I have all over the place. I have AC and DC version (AC plug with a USB port on it and 12v plug with a USB port on it) On a charger like this its impossible for it NOT to work as long as the voltage etc.. is correct. there are only 2 conductors no "signal" wire so there is no way for the reader to make a determination as to what is sending the juice. if its the right juice it just accepts it. ie the sony charger is a "dumb charger" it just puts out 5.2v +tip 1amp power. How you derive that power is not relevant so long as its correctly formatted power. On another note I just put a meter to all my USB ports and they do put out constant power regardless of whats plugged into them. On further reading it seems to depend on the DEVICE circuitry. ie there are 2 ways to "charge" via USB it seems. you can shunt the positive and negative from the USB pin outs to the charging jack (ie dumb charge) in which case plugging it in will work on either the barrel plug or the mini a usb plug. OR you can route the power through a separate circuit in the device. in this case THAT circuit will need to "turn on" to do its job. this is a case where it may be required to have the sony software (only for the miniA jack not the barrel jack) since that circuit may need "conditions" to turn on such as a valid computer connection. This is possible in the case of the reader since when FULLY dead the USB port my not provide enough amps to charge the device (90% of them will) but to play it safe this extra circuit would be designed to not accept the voltage if the amps are too low to not risk damaging the Lithium cells. Every dumb charger I have seen puts out over 1amp which is why they all work fine. Plus there going through the Barrel Plug. NOW if you took a MINI A plug into that dumb charger into the reader it MIGHT not work - I have never tried. I will try it later on and let you all know. but if you use PSP USB plug (get the one with JUST the barrel plug some have the barrel and MINIA) it will work just fine from any DUMB usb charger. Again BARREL plug should work fine (I use over a half dozen of them all work) USB JACK (ie the MINI A port on the Reader) that might not work. Chris Taylor http://www.nerys.com/ Last edited by nerys; 09-01-2007 at 12:33 PM.