[aureusy]

Good day,

I have my iPAQ cradle installed in my car. To power up the iPAQ, I use a car power adaptor (that plug into the cigarrete "lighter"). It works well initialy for the first few days. Now, it still charges well but only when the iPAQ is OFF (standby), when I turn it ON, the power LED behaves strangely. It blinks repetitively at a somewhat rapid rate. The iPAQ does not seems to be charged at all. I'm using a 5V output adaptor, althought the ampere is lower than the original charger adaptor. USB charging (with USB car adaptor) works well but only manage to "maintain" the battery level, that's why I prefer to use the car power adaptor.

By the way, no charging at all if I use a lower output voltage. What is going to happen if I use a higher voltage to charge the PDA (>5V)? Dare not to try yet..


Thanks..

[aureusy]

Good day,

I have my iPAQ cradle installed in my car. To power up the iPAQ, I use a car power adaptor (that plug into the cigarrete "lighter"). It works well initialy for the first few days. Now, it still charges well but only when the iPAQ is OFF (standby), when I turn it ON, the power LED behaves strangely. It blinks repetitively at a somewhat rapid rate. The iPAQ does not seems to be charged at all. I'm using a 5V output adaptor, althought the ampere is lower than the original charger adaptor. USB charging (with USB car adaptor) works well but only manage to "maintain" the battery level, that's why I prefer to use the car power adaptor.

By the way, no charging at all if I use a lower output voltage. What is going to happen if I use a higher voltage to charge the PDA (>5V)? Dare not to try yet..


Thanks..

[Sven]

Don't use higher voltage, though many PPC chargers actually list around 5.4v. That would be OK. Current on chargers is what the device can deliver, not what it does deliver. The current drawn is determined by the device. Typically car chargers have sufficient ummpf (the technical term for current capacity) to effectively charge PPCs while running. Normally the car adapters with a USB socket do too, as the difference is normally just the socket, allowing you to use a standard sync'n'charge USB cable.

Sounds like you said that it worked when you first got it. Is that right? Is the car charger specifically designed for PPCs? The iPAQ listed as supported? Seems that if it did work and now doesn't it might be broken. Yes, one failure mode can be reduced output capacity. PPCs do demand more charging current when on than when off, so if the charger is marginal, you could see what you see.

[Menneisyys]

Originally Posted by aureusy

Good day,

I have my iPAQ cradle installed in my car. To power up the iPAQ, I use a car power adaptor (that plug into the cigarrete "lighter"). It works well initialy for the first few days. Now, it still charges well but only when the iPAQ is OFF (standby), when I turn it ON, the power LED behaves strangely. It blinks repetitively at a somewhat rapid rate. The iPAQ does not seems to be charged at all. I'm using a 5V output adaptor, althought the ampere is lower than the original charger adaptor. USB charging (with USB car adaptor) works well but only manage to "maintain" the battery level, that's why I prefer to use the car power adaptor.

By the way, no charging at all if I use a lower output voltage. What is going to happen if I use a higher voltage to charge the PDA (>5V)? Dare not to try yet..


Thanks..

This question is a very complicated one.

1. most (cheap) car chargers only deliver 1 Amper (or even less), which isn't enough for charging a PDA if its battery is (deeply) depleted and particularly if it's switched on. Then, typically, the needed current is well over 1 Amper - around 1.5-1.7 Ampers with most current PDA's (no wonder the official HP/ Fujitsu-Siemens chargers are all 5V/2A, while the Dell Axim x50(v)/Asus 730(w) chargers are even 2.4A!).

For example, here is a real-world example of the Fujitsu-Siemens PL720's amperage requirements during (re)charging – pretty instructive if you want to know why for example USB/cheapo char chargers don't work with (deeply) discharged PDA's.

2. the more the power consumption, the less the voltage with all voltage converters/regulators, including car chargers. I really recommend this thread for some examples of this effect in practice.

That is, if the charger is forced to produce, say, 1A, its voltage may decrease to, say, 4.6-4.8 (or even less) Volts. Under a certain voltage threshold (about 4.8V for a 5V device like iPAQ's - unlike Dell Axims, which require 5.4V unless they're in the USB charge mode where they're charged with 5V only - see this blog entry), they will simply not charge.

3. the symptom you've described may be caused by two things:

a, something in the charger is dead/doesn't work as good as it used to.

This is highly probable, especially with cheaper ones – after all, during regulating (converting 12V DC to 5V DC) a LOT of heat is made and wear/tear done, which really pushes the regulator chip to its capabilities' end. No wonder some of them just burns out (one of them has also burned on me.)

b, the charge level of your iPAQ battery is considerably lower than in the first few days and this is why it's not more charged, unlike earlier.

If this is the case, you're lucky. Then, all you need to do is charging the PDA up in a wall charger or switch it off while it's on the char charger, it will top up and then, you won't have problems any more.

The most generic solution: get a car charger that has higher amperage output. (See the above-linked Dell blog entry for some Dell-specific examples.)

(Please note that the same stands for USB-based charging as well. The (same) problems with USB charging are even more known because USB hosts are only meant for providing 0.5 Ampers at 5V, which is barely enough for a PDA that is switched on and/or more than slightly depleted.)

(Also posted this post, slightly generalized, to my blog at http://www.pocketpcmag.com/blogs/ind...my_car_usb_cha )

[aureusy]

Swen, Menneisyys, thank you for ur replies.

Swen,

yeah I got it worked at first. The charger is not specifically designed for PPCs. It's for any electronics and allow adjustment of output voltage, selections available are 1.5V, 3.0V, 4.5V, 6V, and 12V. My charger stated 5V. Since there is no 5V to select, I use 4.5V instead. Probably this is what causes the problem..

one failure mode can be reduced output capacity

Ok, maybe I need a right one.

Menneisyys,

the charge level of your iPAQ battery is considerably lower than in the first few days and this is why it's not more charged, unlike earlier.

If this is the case, you're lucky. Then, all you need to do is charging the PDA up in a wall charger or switch it off while it's on the char charger, it will top up and then, you won't have problems any more.

I did a full recharge with original charger and this solve the problem. Thanks for the suggestion.

However, when I removed my PDA from the cradle for a while and then put it back, the abnormal blinking occured again. Full recharge again helps.

I couldn't remember what's the ampere the charger produces because it was only writen in the box (which is no longer here) but if I'm not mistaken it is 1+. My PDA requires 2A.

Since the charger now works well, despite with the somewhat incompatible voltage and ampere. Can I continue using it?

Is my PDA and its battery at risk of damage?

Thank you very much..

[Menneisyys]

Originally Posted by aureusy

I couldn't remember what's the ampere the charger produces because it was only writen in the box (which is no longer here) but if I'm not mistaken it is 1+. My PDA requires 2A.

Since the charger now works well, despite with the somewhat incompatible voltage and ampere. Can I continue using it?

Is my PDA and its battery at risk of damage?

Nope. It's just that 4.5V may be far too low - in cases, as you pointed out, it just won't 'kick in' charging. It won't cause any harm, though.

[Sven]

Originally Posted by aureusy

Since the charger now works well, despite with the somewhat incompatible voltage and ampere. Can I continue using it?

Is my PDA and its battery at risk of damage?

It's never going to work well at 4.5v. You have probably figured out it may only serve to keep a charged battery, full while running. Get one that does the right voltage. It is even posible that a 4.5v charger will accelerated discharge if the internal battery is low to begin with, so I wouldn't use it.

[aureusy]

it just won't 'kick in' charging

You have probably figured out it may only serve to keep a charged battery, full while running

O yeap, I just found out this. The charger did not really charge the pda, even when the indicator showed 100%, because when I brought it back to be charged with AC charger, it took a while (about 3-4 minutes) for the LED to become static again (I guessed it was not fully charged at all).

I've asked many local users in a local forum, they said a car charger of 5V output is very rare. Most available in incremental 1.5V.

HP car chargers are all "cable" type and not for use with cradle.

I have a USB car adaptor. This only "maintain" the battery level, even insufficient to maintain it when I run mapking or mp3s, and does not seems to serve any function when I have the backlight ON.

Since I wish very much to use the cradle in my car, my only option now is to use this USB car adaptor, at least to reduce the rate of power drops, maybe.

I'm wondering whether is it ok to use 6V?

By the way, Menneisys, I read ur article on storage card optimization. Very helpful. What a great work, indeed. I formatted my 1G tanscend 80X SD card with SKTool using FAT16 32K cluster size no backup table. I think got faster now, however, the card becomes "not instantly ready" when I turn my PDA ON. I can't access programs installed in storage card thru' assigned buttons when the PDA is OFF (I meant Standby). How can I solve his?

Thank you.

[Menneisyys]

Originally Posted by aureusy

By the way, Menneisys, I read ur article on storage card optimization. Very helpful. What a great work, indeed. I formatted my 1G tanscend 8 SD card with SKTool using FAT16 32K cluster size no backup table. I think got faster now, however, the card becomes "not instantly ready" when I turn my PDA ON. I can't access programs installed in storage card thru' assigned buttons when the PDA is OFF (I meant Standby). How can I solve his?

This can't be helped - that's a problem with the Windows Mobile operating system - the initialization of memory cards is delayed.

[Sven]

Originally Posted by aureusy

I'm wondering whether is it ok to use 6V?

No.

I am surprised that your Car USB converter doesn't work well. That should be 5 - 5.5v. Is it designed for PPCs or maybe intended for a cell phone. A car certainly has the ability to source sufficient current, but you can build a converter that doesn't handle enough. For the most part every such converter that I've bought, that is sold on a PPC based site, has worked fine.

[aureusy]

Errm, it's for my old TungstenT3. Aren't the voltages the same? Now I guess they might not. I'm not sure coz I gave the T3 to my nephew already. He's now oversea, I'm gonna ask him to check out.

I'll try to get another USB adaptor.

Thank you very much for ur expert info, Sven and Menneisyys. Thanks.