(Solved) microSD circuit not working - looking for ideas / tests

Other Hardware Storage
1

Hello Everyone,

I'm having an interesting problem with a microSD card circuit (custom pcb) and could use some help and / or additional troubleshooting ideas.

Here's the circuit (I know the pull-ups are probably unnecessary):

943×595 4 KB

For some reason, I'm unable to get the card to initialize on that circuit. It fails here:
if (!SD.begin(CARD_CS)) {
// we had some kind of error...
}

I also bought an adafruit SD breakout board, and when I hook it up to the same pins (mostly through an ISP header I use for programming), it works just fine. That board is here:

The biggest difference I can see is the level-shifter. I'm running directly on a 3.3V supply from an Arduino Due and have verified the voltage from Atmel Studio.

Am I missing something obvious? I've resoldered the microSD port once, and am about to replace it with a new one.

2

Resoldered a new socket on - still not working. No shorts between any of the pins. Also, the old microSD socket looks in good order.

3

…

solved it...

...

wasn't using enough solder on the socket SD pin pads and one of them pulled up and was disconnected.

I am apparently terrible at soldering...