rberek
Full Member level 6
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Hi
I am helping to add functionality to a product produced by a friend's company. The added functionality is some pretty simple and straightforward low-speed logic and would implemented as an additional PCB in the product itself.
This product has to endure a rough duty environment in extremes of temperature and must have a low EMI footprint. The product will be standards-tested to ensure it meets the requirements (MIL-spec).
Given that, I elected to produce the prototype with discrete logic rather than a microcontroller, to reduce EMI , and with all through-hole components for added mechanical strength. And it works as desired in testing.
Now, I have to think about productizing it. It is, to no surprise, bigger than I would like, so I was thinking about utilizing SMT devices as much as possible to shrink it. But I am worried about the board becoming more fragile. I should note that there is already an off-the-shelf electronic assembly in the current product that has SMT construction, so the overall man product will still have a surface mount assembly in it regardless of my choice. However, this commercial component has not yet been subjected to the rigorous testing required.
Ultimately I will produce an surface mount version of the board and test it long with the current one, but I thought I would ask in advance for opinions regarding the usage of SMT on rough duty environments. Perhaps the answer is "test it and see" but I thought I would poll the experts first.
My day job is a chip designer for equipment that sits in environmentally controlled rooms so this subject does come up much around the water cooler...
Thanks in advance.
r.b.
I am helping to add functionality to a product produced by a friend's company. The added functionality is some pretty simple and straightforward low-speed logic and would implemented as an additional PCB in the product itself.
This product has to endure a rough duty environment in extremes of temperature and must have a low EMI footprint. The product will be standards-tested to ensure it meets the requirements (MIL-spec).
Given that, I elected to produce the prototype with discrete logic rather than a microcontroller, to reduce EMI , and with all through-hole components for added mechanical strength. And it works as desired in testing.
Now, I have to think about productizing it. It is, to no surprise, bigger than I would like, so I was thinking about utilizing SMT devices as much as possible to shrink it. But I am worried about the board becoming more fragile. I should note that there is already an off-the-shelf electronic assembly in the current product that has SMT construction, so the overall man product will still have a surface mount assembly in it regardless of my choice. However, this commercial component has not yet been subjected to the rigorous testing required.
Ultimately I will produce an surface mount version of the board and test it long with the current one, but I thought I would ask in advance for opinions regarding the usage of SMT on rough duty environments. Perhaps the answer is "test it and see" but I thought I would poll the experts first.
My day job is a chip designer for equipment that sits in environmentally controlled rooms so this subject does come up much around the water cooler...
Thanks in advance.
r.b.