The setup is fairly simple. I used the PPM adapter and the PPM USB-C cable, hooking this into one of my USB-C breakout boards, looping to a second breakout board that goes into the PPM itself. Only ground and CC1+CC2 pins are connected. Then I connected one of my multimeters between VBUS on breakout 1 and breakout 2, measuring the current. The second, less fancy, multimeter just measures the voltage between VBUS and ground. The voltage stays between 15.45V and 15.5V depending on the load (cable and connector resistive losses).
When plugging in the PPM fully charged it still starts the charger only to cut it out within a minute, turning the LED blue.
I wanted to compare the readout from the cheap USB-C meter to my multimeters and the USB-C power meter is clearly good enough for most usecases. The multimeter measures 233mA and the USB-C meter measured 235mA. I also did another measurement with lower current and it’s just as close.
I then removed the USB-C meter to get rid of the additional current consumption it draws, and remove additional losses, this is the measurement setup used for the modes below:
When the PPM is running on the home screen with the battery fully charged this is the current consumption:
Energy saver (average 1.459A x 15.5V = 22.6W):
Normal (average 1.847A x 15.5V = 28.6W):
Presentation (average 2.504A x 15.5V = 38.8W):
The numbers matches the quick measurements I did yesterday using the USB-C meter, so expect that the Android system will use an additional ~0.2A or around 2-3W when decoding video and transferring data over Wi-Fi.
At least my Sherpa 100AC (with up to 3A output) is able to power my PPM and charge it very slowly even in presentation mode. The battery charging can charge at around 30W according to my measurements, so the total power consumption seems like it could go above the 60W (theoretically 70W, but the input current from the USB-C port is limited by the charger chip, reducing charge current to stay below the max). I haven’t figured out exactly which current it limits to (the TI datasheet only shows that it’s possible to limit the total amount of current). I think it’s limiting to either 3A or 4A, likely depending on the negotiated PD contract. I haven’t scoped those signals out yet.
You’re better off if the “15V” output is slightly higher than 15V from your power bank, like the PPM adapter that outputs 15.5V. This is because the input limiter is purely limiting current, not power. The TI BQ chip used as the charger does have a maximum input voltage of 17V (@Philips_Support_P mentioned a while back that the PPM would refuse to negotiate a 20V contract because of some of the chips not handle it, and indeed the limit is 17V).
Interesting… I just noticed that if the PPM is plugged in to the PPM adapter, running in presentation mode and charging the battery at around 50% state of charge the unit still only pulls around 3.3A. This is the usecase where I would have expected the current limit to kick in at around 4A (~1.9A for battery charging and ~2.7A for the system would exceed the limit, but here it drops all the way down to 3.3, leaving only around 0.6A for the battery charging.
However if I plug the PPM into my Macbook Pro charger it pulls 3.5A and the voltage drops to 14.6V (the Macbook charger only supports 3A at 15V). When connecting the PPM to my Sherpa 100AC the Sherpa actually disconnects the output and restarts power contract negotiation periodically as the current consumption exceeds the negotiated contract (the PPM attempts to pull 3.5A from it as well despite the 3A contract).
There’s clearly something odd going on with the input current limiting as a USB-C PD consumer isn’t allowed to exceed the negotiated current (at least not by this much).
Just to share, I received my HyperJuice last night and was able to briefly test it. I think it is able to charge the PPMax. My test results are updated in my post. Thanks.
Thanks @wernerj for your analysis. The projector can actually draw up to 5A (75W) and the adapter can even supply 15V5A. Being outside spec, this isn’t mentioned, but the engineer told me this. For future products I’ve specced them up, to 20V, as that seems to offer better compatibility. Most people can also get away with 3A aftermarket cables then.
Since I wanted to use my picopix an bit farther from the wall, I tried connecting it to a phone charger (15W) and a long USB cable. It looks like the power supply should be sufficient for the picopix, but it does not even register that there is a cable plugged in. Is the supplied cable and adapter the only one that can be used for the PicoPix, or is there an alternative for power supply?
You need a USB-C PD charger that can at least handle 65W and 15V 4A. So both your cable and your charger should meet those requirements. Same holds for powerbanks.
I have been in a labyrinth of powerbanks for the past week to find something that will work, but most of them max out at 15V 3A, which might or might not work based on discussions in this topic.
The PPX can only be charged from the USB-C port labeled USB-C (POWER), and only using a charger that can provide 15V at least 3A. What you could do is use a single socket extension cord to plug your charger in, keeping the USB-C cable at a resonable length. If you find one with a switch it will also allow you to power off the charger when not in use.
I was having power issues with my ppx. I replaced my power adapter/charger with the following and it now works like charm. No power issues or whatsoever, unit charges up to 100% and never turns back to battery mode when connected.
Hi all
I am pretty tech sufficient but have really had trouble understanding the above! What I need is a powerbank that can just extend the output from the PPM ie If I start fully charged and have it plugged into a power bank to get more than the say 3 hours out of it, OR if it isn’t fully charged and I plug it in to a powerbank I can use it for several hours. Both scenarios assume no electric power available (eg using in backyard).
So what do I need to achieve this? If someone can link to an example on amazon Australia that would be amazing.
I know the PPM specifies 15V-4A, what about 15V-5A at 75W? Found this inexpensive charger on amazon only downside is the cable can not be detached as it’s hardwired permanently fixed to the charger with USB C on the other end,
Ok finally placed an order for a charger that hopefully will work, it’s not only a good price and offers an Australian adapter(others as well) but the smallest size I have found so far, because I plan to use this on the ceiling setup and leave it there and not have to unplug it every time I take the projector off, weight and gravity is a concern, I have already got a separate Fasgear 100w cable that works great so now I have 2 sets of charger and cable, 1 for ceiling in the living room and 1 for the bedroom, should be quick and easy to go from room to room now,
