BUS PIRATE: USB Micro B connector test


USB Micro B is the connector of the moment, but we haven’t had a very good time working with it. The bog-standard Chinese generic Micro B connectors on Bus Pirate v5 and Bus Pirate NG1 break constantly. We tested a Micro B connector with through-hole support tabs on the latest Bus Pirate PCBs. It turned out really well.

Standard Chinese USB Micro B connector


A ton of mom and pop factories around Shenzhen churn these out by the bucket load. It seems like a great part: ubiquitous and cheap, doesn’t require a special board slot, versions with extended leads and centering pegs are easier to hand solder. Unfortunately, every connector soldered by every member of our team has eventually decided to exit the PCB.

This connector is optimized for paste stencil and reflow soldering. Most support should come from two solder pads under the connector that are impossible to reach with a soldering iron. Maybe it could be done with hot air, or the QFN “solder from the bottom of the board through a via” hack.

Connectors with supporting through-hole tabs


The generic Chinese connector (left) has six solder pads holding it to the PCB. Four can’t be reached with a soldering iron – the two under the front, and the two recessed pads at the back near the pins.

A Molex 47589-001 (right) with through-hole support tabs went into the next revision of the Bus Pirate boards. The tabs aren’t long enough to go completely through a 1.6mm PCB, but they can still be soldered in place from the top of the board. It’s much more expensive – essentially free vs $0.50 each – but we’re optimizing for hand assembly, not production.


Now we’re living the dream. The four tabs are really secure, and we don’t have to treat the prototype like glass. The next step is to find the most widely available Chinese equivalent.




Join the Conversation


  1. Could you put holes through the SMT pads of the Chinese connector and solder it from the back of the board?

    MicroUSB connectors have this problem a lot; even on professionally manufactured boards. They seem to really need a case around them with significant mechanical engineering applied for strain relief, and even then they’ve come off.

  2. Is the 1.6 mm PCB a “must have” or could you go to 1.2 mm, 1.0 mm, etc?
    (sorry, put this comment on wrong article before)

  3. Why not standard USB-B , it’s very robust and, sincerly, who can’t afford having a standard USB cable at his desk? how many time do you travel with your buspirate without having the cable with it? An USB-B just do the job and is very robust and doesn’t need a case to be reinforced.

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