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My challenge is, how can mount a SMD component in a 45 degree angle raised from the PCB.

I am doing a temperature sensing device, which is intended to be mounted on a wall, hence the PCB will be parallel to the wall, but is going to measure the temeprature on the surface of the floor. The temperature sensor for this device is an IR sensor TMP007 from TI.

So what I need is a genius way on how can I mount the sensor, so it points towards the floor, with an angle between 45 and 60 degrees in relation to the PCB (0 degree will be mounted on the PCB) so it is pointing towards the floor.

The mounting method should preferably be suitable for mass production, so not something to labor intensive.

Hope some one have some good ideas or solutions.

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    \$\begingroup\$ Use a gold reflector to re-direct the beam. \$\endgroup\$ – Andy aka Jun 6 '15 at 10:27
  • \$\begingroup\$ Well, I'd try to mount the PCB itself at 45 degrees... For example, having a triangular enclosure (a cube cut into half diagonally) would make this easy. \$\endgroup\$ – Laszlo Valko Jun 6 '15 at 10:30
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You do not want to mount the SMD component in any manner except for flat on its pads as the package was intended to be mounted. This is especially true of the TMP007 device since it is in a mini BGA package.

If you need unique mounting orientations of the component then you should be considering how to orient the circuit medium upon which the component is mounted. There are known - production feasible - methods for joining two PC boards at right angles. One method interposes the two boards using a connector of some sort. Another method has the main board slotted with the sensor board inserted into the slot and then adjacent copper lands are hand soldered together. Yet another method would have the sensor mounted on a flex circuit and then the flex joined to the main board via an FFC type connector.

The FFC flex circuit is likely to give you the overall best solution. You mount the component on one end of the FFC and a small board to flex connector on the other end. This gives you a solution that can be built up as a subassembly without having to do soldering at final assembly.

enter image description here enter image description here

I could even envision that you make your device package have a fold out arm that has the flex inside with the sensor captured at the end of the arm. The user would hinge the arm out to place the sensor at a suitable position to make useful measurements.

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  • \$\begingroup\$ Sorry, didn't see you included flex circuits in there before I posted my answer. Edge soldering the boards together is an excellent low cost idea, though one needs to make sure the boards are supported by something else (even if it's glue) to avoid stressing the solders. +1. \$\endgroup\$ – Mister Mystère Jun 6 '15 at 11:28
  • \$\begingroup\$ Yes was aware the TMP007 should be mounted flat on a PCB. The idea with a slot in the "main" PCB which would fit a small PCB for the TMP007 was what I had in mind myself, but was not sure if this could work, of course it means someone has to do some soldering, but maybe the best and easiest way, and I have a plastic frame attached to the main PCB which support an OLED display, and could easily be extended to also support the PCB for the TMP007. \$\endgroup\$ – JPRV Jun 6 '15 at 15:59
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Usually this is done via flexi-rigid boards: a multilayer PCB where some parts of the PCB have no layer but the layer where flexible insulated traces are, effectively linking several PCBs with a flexible ribbon. Some of those don't even have the standard PCB materials, components are directly soldered on top of the flexible combo (flexi boards). enter image description here

However those circuits are not cheap. The quick and easy way would be to mimic that by making a dedicated PCB for your sensor (or buying a breakout board off e.g. sparkfun if you want to save on the costs), mounted on a bracket, and use some sort of connector (or even flying wires soldered directly to the breakout board) to connect it with your motherboard.

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  • \$\begingroup\$ Was thinking of the flexible PCB, but then I need an easy way to keep the part with the component in a fixed position, and the same osition for every print I do. Not an esay task I think. \$\endgroup\$ – JPRV Jun 6 '15 at 16:01
  • \$\begingroup\$ Set aside the obvious 90° that can be achieved with edge terminals (like RAMs on motherboards), you will have to make a bracket of some sort to ensure the sensor is at the angle you want it to be, regardless of your choice regarding connection technology. \$\endgroup\$ – Mister Mystère Jun 6 '15 at 23:50

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