Test WIIM pro+ with different power supplies

I'll try to simplify. Many people are trying linear power supplies instead of the provided noisy switch mode power supply. But linear power supplies are dumb, whereas Wiim uses a USB C power connector. A USB C power connector negotiates with the power supply the voltage and current available. So if someone uses a dumb linear power supply, it may not be communicating its capability to the Wiim to provide more than .5A current and may degrade the performance of the Wiim instead of improving it. That is what I am trying to ascertain. Halfway thru this, only conclusion so far is that the Wiim does negotiate voltage levels with the power supply. I am trying to find out if the Wiim also negociates the current level as well and uses that information to limit the current used.

You do bring up a point I neglected. I tested the included charger with the Wiim but I did not test the charger with the included cable.
thank you ;-)
(my modest "a 0.6a" tests were only in aac radio mode not 192k24... after upgrade , what are the overconsumption situations observed?)
 
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You do bring up a point I neglected. I tested the included charger with the Wiim but I did not test the charger with the included cable.
Included cable doesn't allow any negotiation, it has probably both D+/- unwired. So it will be dumb.
I don't think that the Pro relies on the charger capabilities.
 
The most common scenario which I've seen when using dumb LPS or SMPS chargers, was identifying itself as DCP1.5A when a correct usb cable (or barrel to usb adaptor) is used.
 
Since this supply is a PD supply, it clearly negotiated with the Wiim to supply 5V and the supply advertised 2.4A was available. Why would this be important? Because the default is 5V at .5A.
Default current of 0.5A is for SDP and computer usb ports. In case of the chargers it will be rather DCP and 1.5A when possible, for backward compatibility without any negotiation.
 
Default current of 0.5A is for SDP and computer usb ports. In case of the chargers it will be rather DCP and 1.5A when possible, for backward compatibility without any negotiation.
Can you point me to documentation that states that? So far all the documentation I have read about USB C protocols with D+ and D- unwired state that 5V .5A is default.
 
Can you point me to documentation that states that? So far all the documentation I have read about USB C protocols with D+ and D- unwired state that 5V .5A is default.
I didn't say that this is for unwired D pins. It's for shorted ones just like it is for the stock PSU, common chargers and barrel to USB adapters.
 
I didn't say that this is for unwired D pins. It's for shorted ones just like it is for the stock PSU, common chargers and barrel to USB adapters.
Are u sure? I compared several and the D pins are open. I think that is the common situation. How did you determine this? Would be very interested to see if I missed something. I have several barrel to USB adapters and the Dpins are all open. I had to make a custom cable to short the D pins.
 
Are u sure? I compared several and the D pins are open. I think that is the common situation. How did you determine this? Would be very interested to see if I missed something. I have several barrel to USB adapters and the Dpins are all open. I had to make a custom cable to short the D pins.
I am sure. I've tested 2 adapters, one coming with Sbooster and another with Nirvana SMPS, using a breadboard and multimeter - D pins were shorted. The same thing with the stock Pro charger and few other wall chargers.
 
In all these cases the charge mode was identified as at least DCP1.5A (or Apple 2.4A when voltages were indicating it) by my Ruideng TC66C tester. It won't work like this when the stock Pro cable is used due to the lack of D wires, charge mode is reported as 'unknown'.
 
Thank you. I got a cheap tester RD TC64 and for all the dumb type supplies it read Samsung, whatever that means. With an appl charger it read Apple 2.4A and with my custom cable where D cables shorted it read QC2.0. I have on order a Finsri tester, which is supposed to be much better.. When I test with barrel to USB C adapters, it reads Samsung. It never reads DCP1.5A

It seems from what you say, many companies short the D cables. But if you use the stock pro cable, with the stock power adapter it doesnt report as 1.5A?
 
"plus"-charger samsung 2.4 after reconnection dcp1.5a
tc-66c
ps all of transformer i try is "dcp1.5".. and same thing with an old a 1A!
 

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No, stock Pro cable has no D wires at all.
This makes me confused because if one connects the stock charger with the stock cable to the Wiim Pro, then according to what you say, there are no D wires and therefore it defaults to 5V .5A connected to the Wiim Pro. Why would Wiim have a 1.5A charger but only have it communicated to the Wiim to provide only .5A?
 
"plus"-charger samsung 2.4 after reconnection dcp1.5a
tc-66c
ps all of transformer i try is "dcp1.5".. and same thing with an old a 1A!
I never get DCP1.5 except at the beginning before reverting to Samsung.
 
there are no D wires and therefore it defaults to 5V .5A connected to the Wiim Pro
There are no D wires so the Pro is not aware of PSU capabilities. I assume it simply tries to receive the current it needs.

Why would Wiim have a 1.5A charger but only have it communicated to the Wiim to provide only .5A?
Because the Pro obviously doesn't care about any communication with the charger? Its usb port acts like a simple 2 wires barrel port.
 
This makes me confused because if one connects the stock charger with the stock cable to the Wiim Pro, then according to what you say, there are no D wires and therefore it defaults to 5V .5A connected to the Wiim Pro. Why would Wiim have a 1.5A charger but only have it communicated to the Wiim to provide only .5A?
yes i think @onlyoneme is right. they recommend (and provide 1.5A) because of tolerances they don't want someone to buy a 0.6A rated charger (that only delivers say 4.2V at load for example) to then have issues with the wiim unit not receiving enough power
 
According to the USB protocols, if there is no D wires the protocol defaults to 5V .5A. There is no protocol under USB where it acts as a simple 2 wire barrel port. That was the whole point of my exercise, to determine if the Wiim negotiated under USB protocols the voltage and current it receives. I am sure it negotiates the voltage and therefore does not act as a simple 2 wire barrel port. If Wiim wanted to do that, they would have put a 2 wire barrel port instead of a USB C connector.
 
I am sure it negotiates the voltage
What makes you so sure here? There are devices on the market which use the USB port for charging only and they lack any data wires. You've never seen a USB c ports for DIY with 2 wires only?


If Wiim wanted to do that, they would have put a 2 wire barrel port instead of a USB C connector.
If WiiM wanted a voltage negotiation, they wouldn't attach a cable without D wiring.
 
What makes you so sure here? There are devices on the market which use the USB port for charging only and they lack any data wires. You've never seen a USB c ports for DIY with 2 wires only?



If WiiM wanted a voltage negotiation, they wouldn't attach a cable without D wiring.
Here is the logic (which could be faulty) - I attached a PD power supply and it connected up as a AAPL 2.4A, 5V supply. How would it know to put out 5V if it wasnt polled to do so? My conclusion was that the Wiim Pro was polling the capability. That was the logic.

That said, there was a sure fire way to make sure, I opened up the case and started looking for a USB C controller power chip like the TI TPS2511. Something that was a USB charging port controller and current limiting switch near the USB C port. It would be a 8 pin SMD. There was no chip nearby the USB C port. That supports your theory in part. If I look at the USB port traces on the board, D+ and D- are connected to some components marked ED, so there are connections to the data wires (lines 7 and 8), but are passive. If I measure the resistance between the D+ and D- pins with the Wiim unpowered, I read an open. If I measure the voltage between D+ and D- with th Wiim powered, using the USB C meter and a dumb supply with a barrel it reads D+ is 1.17V. I have no idea where the D+ voltage comes from if the D lines are open!

BTW, thanks for your input. i am trying to learn what is going on, so your comments are helpful!
 

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What makes you so sure here? There are devices on the market which use the USB port for charging only and they lack any data wires. You've never seen a USB c ports for DIY with 2 wires only?
I have never seen a commercial device (non-DIY) that uses a USB port with 2 wires only and does not negotiate any protocols. That is why I am confused, I did not know these existed. These certainly do not follow the USB-IF standards.
 
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