3
\$\begingroup\$

To mount an MPXV7002 pressure sensor (SMT) on a PCB, it has to be raised above the board by about 3 mm to allow the plastic tubing to be attached to the pressure ports. This is an 8-pin device that normally surface mounts with the ports off the end of the board, however, restrictions dictate the ports (that are at the level of the bottom of the device case) have to be within the board. Thus the need for a way to elevate the sensor with something conductive that will surface mount to the board (or through hole) and allow the sensor to surface mount to it. Is there such an item available, other than standard straight male pin headers?

http://www.nxp.com/files/sensors/doc/data_sheet/MPXV7002.pdf

\$\endgroup\$
  • 1
    \$\begingroup\$ Whats wrong with internal holes/slots? \$\endgroup\$ – Erik Friesen May 4 '16 at 20:02
  • \$\begingroup\$ You could make adapter pcb, but it really sounds weird \$\endgroup\$ – Gregory Kornblum May 4 '16 at 20:04
  • \$\begingroup\$ If this is a production item and you have to do it that way, you might be able to find a PCB fab that would make a double-thickness board that you could use as a sub-module to hold the part, with castellated edge contacts like so many (typically RF) sub-modules use. A sub-module mounted on through hole pins could be done with ordinary 1.6mm or whatever PCB fabrication. \$\endgroup\$ – Chris Stratton May 4 '16 at 20:08
7
\$\begingroup\$

You could have a slot just wider than the tubing around an inch long just under the port and extending outwards.

Something like this: enter image description here

\$\endgroup\$
  • 1
    \$\begingroup\$ As far as I'm concerned, it's less could, and more should. Provided the no-edge is truely as hard a requirement as it is stated to be. +1 \$\endgroup\$ – Asmyldof May 4 '16 at 20:42
  • 3
    \$\begingroup\$ The question indicates that the ports must be level with the bottom of the device case, so the ports would be near the edge, just not (fully) overhanging. In this case, you should put a notch in the edge of the board. Basically the same thing as a slot, just not fully enclosed. \$\endgroup\$ – mbmcavoy May 4 '16 at 21:59
  • \$\begingroup\$ The sensors have to be located with the ports away from the edge of the board because the PCB fits next to, and in the same plane as, an Arduino micro-controller, and the tubing exits a preconfigured box at the other end of the Arduino so the sensors have to face the Arduino. Since an SOIC to DIP Adapter requires more real estate than is available, I guess the only option is a slot in the board to accept the tubing. Question: Will PCB manufacturers make slots inside the outer boundaries of a board as you suggested? \$\endgroup\$ – DavidCyr2000 May 12 '16 at 0:09
4
\$\begingroup\$

Three options:

  1. Mount at Edge - probably the most sensible option is to simply mount the part at the edge of the board. This way the ports overhang the edge of the board and you don't need to worry about height. You could also mount at the edge of a slot in the board for the same effect.

  2. SOIC to DIP Adapter - You can get SOIC to DIP adapters (or make one) which basically are a small PCB with pin headers for plugging in to a DIP IC socket. You would solder your sensor to the adapter so that the ports overhang the edge of the adapter PCB. Then you can position a DIP socket anywhere on your board and plug in the adapter. This will give the required height clearance. You don't necessarily have to use a DIP socket, if you design your own adapter you can use any board to board connector you want.

    You could design something like this:

    Adapter

  3. Cable Mount - Pretty similar to option (2). You have an adapter board with the sensor mounted on it. You then attach a cable to the adapter so that you can position your sensor at a useful place in whatever enclosure your design is put in.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.