How interchangable are the mini-USB power connectors used for say a Garmin GPS and a Motorola Razr cell phone? I plugged my cell phone into my Garmin 12V DC car charger and it seemed to charge okay for a day or two, but now my cell phone crapped out on me. Wasn't charging it, hadn't charged it in several hours and it locked up on me. Was finally able to shut it down and now when it powers up I have no bars.
If the mini-usb format is a standard, shouldn't it deliver the same power to all devices??
USB charger/connections Garmin/Motorola
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[JiF]KellysHero
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USB charger/connections Garmin/Motorola
You've got to ask yourself a question: Do I feel lucky? Well, do ya, punk?
Re: USB charger/connections Garmin/Motorola
I do not know about the schematics of that charger thingy but i do know by own bad (i.e. destructive) experience that some mobile phones do not only need correct voltage but also correctly limited charging current.
On real USB, you will not get any more that exactly 5 VDC with a peak maximum current of about 2 ampere(until most mainboard USB fuses blow, that is
).
In car socket you may have any current and the voltage is up to the circuits quality in the charger.
If your garmin charger is the low cost design, there´s probably no current limiter in it but - if not that transistor/zener diode solution - a linear IC like that lm7805 or lm7805cv. These do work somehow good enough for most applications but first they do give out more that the rated 5 VDC (not so much more but output voltage is over the rating and is also depending on what power is drained) and then they tend to let the whole input voltage through when malfunctioning (this you could check. Once they blow, they keep blown).
From what you wrote i would guess that your car charger let through too much current and/or slightly too much voltage. Li-ion batteries do not like that and their built in electronic tends to play dead after such atrocities although the battery itself might still be in order.
Mobile batteries are a designed quality pain. NiCad/NimH cells are always designed so crappy that charging process is determined by energy state of one of the cells, Li-ion are black boxes,where nobody knows when and why they´ll play dead. What i did some times and did work some times is to recharge any of the first cells with every cell for its own in a modified computer charger and to dismantle and disconnect the electronic from the latter ones for a short period of time.
This is dangerous and will ruin any warranty so i do not suggest it but tell you before you read about that on less trustful sources that those possibilities exist.
One little hope might be to discharge the mobile battery by hand which also sometimes works. Abuse a small(!) toy motor and connect it to plus and minus of the battery until it stops turning. Then remove the connection, wait for about 10 minutes and reconnect again until motor stops. After this try charging with the original adapter. Worked with nokia battery don´t know if motorola is toy compatible.
On real USB, you will not get any more that exactly 5 VDC with a peak maximum current of about 2 ampere(until most mainboard USB fuses blow, that is
).In car socket you may have any current and the voltage is up to the circuits quality in the charger.
If your garmin charger is the low cost design, there´s probably no current limiter in it but - if not that transistor/zener diode solution - a linear IC like that lm7805 or lm7805cv. These do work somehow good enough for most applications but first they do give out more that the rated 5 VDC (not so much more but output voltage is over the rating and is also depending on what power is drained) and then they tend to let the whole input voltage through when malfunctioning (this you could check. Once they blow, they keep blown).
From what you wrote i would guess that your car charger let through too much current and/or slightly too much voltage. Li-ion batteries do not like that and their built in electronic tends to play dead after such atrocities although the battery itself might still be in order.
Mobile batteries are a designed quality pain. NiCad/NimH cells are always designed so crappy that charging process is determined by energy state of one of the cells, Li-ion are black boxes,where nobody knows when and why they´ll play dead. What i did some times and did work some times is to recharge any of the first cells with every cell for its own in a modified computer charger and to dismantle and disconnect the electronic from the latter ones for a short period of time.
This is dangerous and will ruin any warranty so i do not suggest it but tell you before you read about that on less trustful sources that those possibilities exist.
One little hope might be to discharge the mobile battery by hand which also sometimes works. Abuse a small(!) toy motor and connect it to plus and minus of the battery until it stops turning. Then remove the connection, wait for about 10 minutes and reconnect again until motor stops. After this try charging with the original adapter. Worked with nokia battery don´t know if motorola is toy compatible.