PGA2040 not connecting via USB

Recently I bought a PGA2040 to experiment for a simple GPS Tracker project. I am currently trying to connect it via Micro USB to my computer to flash firmware. The PGA2040 doesn’t appear on the computer as a device.

Here are some pictures of the soldered PGA2040 and USB breakout board:

Does anyone have any ideas for why this may be happening?

Poor soldering may be the culprit. I see at least one cold solder joint in the picture.
The Ultimate Guide to Soldering (

It’s a bit difficult to see what the wires are connected to in your photo, especially at the USB breakout end, but it doesn’t look like the VBUS pin on your USB breakout is connected to anything - it should be connected to VB on PGA2040.

You’ll need to temporarily connect the BS pin to ground while plugging in the cable for it to show up in BOOTSEL/mass storage mode - that’s what the red jumper is doing in the photo.

Sorry for the bad photo quality, the blue cable in the photo is connected to VBUS. For connecting BOOTSEL to GND, should I do it after plugging the USB cable and then disconnect the BOOTSEL from GND?

On a PICO it’s
Press and hold Boot Select
Plug in USB cable
Wait a few seconds and release Boot Select.

So for you it’s
Ground Boot Select
Plug in USB cable
remove ground.

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