Hi there!
I am working on a project where I want to fire a mini Push/Pull Solenoid and power it through the a USB-C Breakout board & the official Raspberry Pi Foundation USB-C power supply (which says it will support 3A @ 5V).
The problem I am having is that I am only able to draw 0.6A out of it -- and when I do I experience a voltage drop between VBUS and GND from 5.2V down to 4.25V. This is a problem because I want to also power a Raspberry PI Zero W on this same circuit and it requires 5V. The product details on the Adafruit page says I should be able to draw at least 1.5A from the USB-C breakout board and the power supply says it can supply 5V @ 3A.
The USB-C breakout board I am using is
this Adafruit one. I have also tried the sparkfun one and I am seeing the same limitation. I have tried both the Raspberry Pi power supply and an Apple USB C supply.
Here's my simplified circuit:

And here is the voltage drop that occurs when the solenoid is activated with the button:

Here is the draw in amps when activated:

The voltage drop is not temporary, it lasts as long as I keep the solenoid activated.
I suspect this is due to the default USB supplied power of 500mA @ 5V = 2.5W. This is suspiciously close to my measured amps * lowered voltage of 0.63A * 4.248V = 2.68W.
Here is a picture of the test setup I am using. I added and LED as a little indicator:

Here's what I've already attempted to troubleshoot:
- I've verified that there is 5.1k Ohms between CC1/CC2 and GND. The breakout board does this -- I just wanted to verify. The
USB app note linked by Adafruit on the board page says this will give at least 1.5A (Section 3.2, Table 7).
- I've measured the voltage between CC1 and CC2 and it's 1.77 volts. The above document indicates (SS 3.6; Table 9) that this means that the power supply is advertising up to 3A, which we expect. So.. why can't I draw that?
- I've tried shorting D+/D- as I've read online this can indicate desiring a higher current. It didn't work!
Can anyone help me figure out why this thing is not supplying more power? What am I doing wrong?
I am hoping one of the folks here is knowledgable enough in USB.