Prime Power Switching Adapter

[Skyblues]

I've been looking to get another Switching Adapter for my Prime. Does anyone know where I can get one? I did an internet search but didn't find anything similar. This is the adapter that comes with the Prime so you can plug it into the wall to recharge.

Info on adapter:

Switching Adapter
Model: DSA-5CAA-05 050100
INPUT = 100-240v 60Hz 0.2A
Output = +5V 1A
Level 3

Thanks,
Jim

[matthiaspaul]

(09-20-2015 03:52 AM)Skyblues Wrote:  Output = +5V 1A

While Hewlett-Packard was (among Apple, Sony, Samsung and a few others) one of the companies who have implemented their own proprietary and incompatible USB charging schemes in the past, the HP Prime was introduced in 2013, therefore I strongly assume that it follows the USB Battery Charging Specification (BCS) 1.2 (scanning the manual revealed nothing, though).

So, any USB power adapter compliant with the USB BCS 1.2 and capable to deliver 1.5A at 5V should work, regardless of manufacturer. While based on the label of your adapter the Prime does not seem to draw more than 1A while charging, I recommend to go for a DCP (Dedicated charging port) adapter providing not only 1A but up to 1.5A, so that the adapter can be used universally for any devices following the BCS. After all, the whole idea of the USB Power Delivery Specification (PDS) and the USB BCS is to finally have a universal power delivery, charging and power connector standard for an extremely wide range of consumer electronics devices regardless of manufacturer in order to avoid unnecessary environmental pollution by reducing waste.

While there should be an abundance of suitable DCP adapters available, it is also very easy to build your own: All you need is a power adapter delivering up to 1.5A at 5V and a suitable USB connector. Connect the +5V wire to VBUS (pin 1) of the connector and 0V to GND (pin 4). Then short the D+ (pin 2) and D- (pin 3) pins in the USB connector. A device supporting the BCS will find out that it is connected to a BCS compliant DCP by detecting the short between the otherwise floating (no pullups or pulldowns in the adapter!) D+ and D- lines. If the device is not BCS compliant, the short of the data lines will not cause any harm, but the device may charge very slowly (with 0.1A only) or not at all. (There are also dumb devices out there, which don't care about negotiation at all and just draw the power they need - however, such devices are not only not compliant with the optional BCS, but they actively violate the USB specification and would not be allowed to carry the USB logo. Therefore I don't assume that the Prime is one of them. Either way, in this particular case it would work anyway, for as long as the source provides enough current (at least 1A per your label).)

Greetings,

Matthias

[Tim Wessman]

Basically, *anything* that provides power from a usb port will work fine. I've not yet seen a charger that has a "usb port" not work properly. That includes some rather sketchy junk ones from markets in "questionable" places.

So as suggested, if you plan to use it with other devices that do require a much higher charge (tablets primarily) then you might want to pay a bit more. Else any old charger will work.

[matthiaspaul]

(09-20-2015 02:51 PM)Tim Wessman Wrote:  Basically, *anything* that provides power from a usb port will work fine.

This would suggest that the Prime does never draw more than 0.5A, as classical non-PD- and -BC-aware USB 1.x/2.x ports would allow only up to 0.1A without negotiation and up to 0.5A after successful negotiation with the host. Negotiation, however, implies that the data lines must not be shorted, but connected to a suitable USB host instead (or it would require a "smart" charger actively emulating an USB host).

The manual states that a full charge of the 1500mAh battery takes about 4 hours. With some safety factor this would suggest a charging current of not more than 0.5A as well.

One open question is if the Prime is BCS-aware and charges faster when it detects a charging downstream port (CDP) or dedicated charging port (DCP) allowing more than those 0.5A.

Another open question is how long it takes to charge the Prime if the power supply would only provide the 5V, but neither emulate an USB host nor short the data lines. If in this scenario the Prime would still draw more than 0.1A (taking less than 15 hours for a full recharge), it would violate the USB specification...

Tim, can you confirm or deny BCS compliancy? I might have overlooked it somewhere in the manual, but if the Prime would be BCS 1.2 compliant, I suggest to explicitly mention it in the technical data, as it would be good advertisement for the device.

Greetings,

Matthias

[Skyblues]

Thanks for the info.

I just searched amazon.com and found one that has an output of 5.3V, 2A. Would this work?

http://www.amazon.com/gp/product/B00N33Y...YX91Q086GN

I thought I read somewhere that you could use a higher amperage because the device would only use what it needs. Is this true? I'm also not sure about the extra 0.3V with this charger, though.

I couldn't find anything that has exactly 5V, 1.5A.

Also, what would one look for in a car charger for the Prime?
Would this work?

http://www.amazon.com/Universal-Capacity...2661618011

My wife and I are going to be doing some traveling soon and I want to take my Prime with me.

I just want to make sure I don't fry my Prime ... I can't afford another one, at least not yet :-)

Thanks,
Jim

[matthiaspaul]

(09-21-2015 01:42 AM)Skyblues Wrote:  I just searched amazon.com and found one that has an output of 5.3V, 2A. Would this work?

Strangely enough the link doesn't work for me, but 5.3V is outside the USB specification.

Quote:I thought I read somewhere that you could use a higher amperage because the device would only use what it needs. Is this true?

Of course. (Just to be sure, please note that this applies to currents ("amperage") only, not to voltages!)

The source (power supply) will have to cope with the maximum current the sink (device) will draw. So, based on your label of the existing adapter, anything larger or equal to 1A is fine, according to Tim's comment even anything larger or equal to 0.5A should be fine as well (but Tim's comment is unfortunately too vague to derive hard facts from it - I hope he'll find the time to clarify).

However, the USB BCS spec allows devices to draw up to 1.5A and unless you find an adapter with 1A for cheap/free, it is wise to go for an adapter which can provide 1.5A (or more) so that your investment will not only work with the Prime (and other devices needing only 1A or less), but with any devices covered by the spec, so that (in the foreseeable future) you will no longer have to care about if it will work or not.

Quote:I'm also not sure about the extra 0.3V with this charger, though.

The USB spec allows up to 5.25V, so strictly speaking 5.3V is too much. While it is unlikely to break anything, 0.3V is already quite a difference in microelectronics. The fact that it is not 5.0V indicates an unregulated adapter (that is: outdated and inefficient technology).

Quote:I couldn't find anything that has exactly 5V, 1.5A.

2A (or more) will work as well, of course.

Greetings,

Matthias

[Skyblues]

Thank you!

Jim

[retoa]

I charged it with the USB2 port of my PC and with any USB charger for my phone, tablet, GPS, photo.
ZTE, LG, Samsung, Garmin, Canon, third parties, I have many USB chargers, all work fine.

Greetings

Reto