Parts: microSD memory card holders
posted Oct 6th 2008 12:24pm by Ian Lesnetfiled under: news, parts

SD cards add cheap persistent memory to your project, but the holder takes a lot of board space. A smaller option is the microSD flash format. MicroSD cards are compatible with regular SD cards, and most come with a free adapter. We looked at four holders for our mini web server. Which should you choose? Read about our experience below.

Here’s a breakdown of the microSD card holders illustrated above:
Alps SCHA1B0100 $1.27 – Can you see pins through the holes in the first holder? They ‘re hard to see, and almost inaccessible. We didn’t find this holder very useful for prototyping.
JAE ST6S008V4AR1500 $1.46 – This is another model with pins located at the front, but these are further forward for easier access. It’s still going to be a pain to solder, avoid if possible.
SparkFun PRT-00127 $3.95 – Finally, a holder with pins at the back. This is a fairly easy-to-solder part, but it’s not ideal. The soldering tabs are very small and slightly recessed under the shield. It’s also the most expensive microSD holder we’ve seen. SparkFun has a Cadsoft Eagle footprint for this part in their library. We think Molex 538-502702-0891 ($3.58) is probably very similar. We used this holder with the mini web server.
Alps SCHA2B0300 – $1.27 – The long pins along both sides of this holder are easy to solder. The holder is reversed, meaning the card inserts upside-down. Reversed holders seem weird on an all surface mount board, but they fit nicely in through-hole designs. There’s no Eagle footprint yet, but we’ll send an SCHA2B0300 to the first person who makes one; here’s the datasheet (pdf).
Check out our previous parts posts: 0.1uF decoupling capacitors, the LM317 adjustable regulator, and tactile switches.

Does it have to be Cadsoft Eagle? I’ve used this part before and have the footprint for ExpressPCB.
Posted at 12:38 pm on Oct 6th, 2008 by Matthew