nevermind the USB-C, power question

mardukes

Mfr Part#: LS-1920-C+A -- Inland 3A USB Type-A & USB Type-C Wall Charger

The spec says "Output Voltage- 1 x USB Type-A 18 W"

I thought the USB-A spec was limited to 3 amps therefore 15 watts but, my question is about the wire. Can any old USB-A to USB-mini handle 15 to 18 watts? And, of course, is this 18 watts (or even 15) accurate?

I'm wondering about powering small amplifiers. Probably rarely reaches max power consumption but, will be long running.

TIA

md

Vaganza

You are looking at a limit of 7.5 W (5V @ 1.5A) on standard USB-A, but that may just be what is provided by a USB bus on a motherboard. Chargers can likely pump through more using the same wire, take a look at this and see if it helps. https://hardwarerecs.stackexchange.com/questions/16164/what-is-the-max-usb-cable-type-a-male-to-type-c-male-volt-current-wattage-possib#:~:text=The%20maximum%20amount%20of%20power,voltage%20that%20they%20both%20support.

mardukes

This link is good information for USB-A to USB-C and the 7.5 watt statement may very well be true. However, this item says 18 watts. Someone in that thread wrote that he heard it could be a hack of putting juice on all 4 wires at the A end -- which would mean the circuitry would have to resolve it at the C end. But that would be a special cable i.e. not one we would expect to come with an iPhone or such nor one included with this product. So, I'm still looking for technical info.

thanks

md

PS- Inland folk, how are you putting 18 watts where 7.5 is supposed to be the limit?

PPS- I do have a wart over here that is USB-A and 2 amps.

Vaganza

This is my biggest complaint with USB-C. While the interface looks the same, what that port does depends heavily on the chipset it is connected to and which of the half dozen cable types you use. I vow to only carry at least the 20 gbps cables knowing that that cable will do nearly anything I ask it to. I have run into so many issues where people are trying to carry video over a charge/sync cable.

mardukes

It's not my biggest complaint but, Inland support directs us back to Microcenter and it appears my question will languish while these guys sit around with their thumbs up their asses.

Vaganza

Inland is Micro Center's brand which is why they would direct you there. The cable itself should support what amounts to essentially a power brick, the limitations in the specification are more directed to USB.

mardukes

I got a reply from support. Seems there is the possibility that a non-A-to-C cable might not be rated to carry that "high power" wattage. Funny -- isn't that the reason I asked the question. Anyway, I read another thread where someone says an A-to-Micro is spect to a max of 9 watts. So, even if I calculated some number according to the wire gauge, I don't know about the micro connector -- I have to figure the A connecter is rated for 18 watts as, well, there's the port.

mardukes

I got more information from support that cleared up a misconception of mine on Power Delivery. Now I understand this part of the spec:

Output Voltage: 1 x USB Type-A 18 W Power Delivery:

-- 3 A @ 5 VDC;

-- 2 A @ 9 VDC;

-- 1.5 A @ 15 VDC

So the first one, 5 volt, IS only 15 watts.

On the question of cable, PD only specifies certification for it at much higher amps. So, I think any old A-to-micro should work just fine. No promises.