Post
by abecedarian » Thu Dec 25, 2014 6:32 am
Yeah, I'm drawing in Eagle.
The board I'm thinking of doing would be a 2-layer, 5cm^2 module, maybe smaller once I start on and optimize layout. The thought here is many board fabs have price breaks and such, and that is a common size for many 'generic' modules, easy to panelize and such, and I am planning on having 3mm holes at each corner to facilitate secure mounting. My use would have this mounted on top of another board, secured at each corner, and with short pin headers between this and the parent board, not with off-board connectors. If I were going to do some sort of connector system, the board itself would probably only provide for wires to be soldered in, which would lead out to a female/male, 5 position, sealed connector, 14 AWG/1.63mm diameter wire, pigtail / harness pair similar to what many sensors would otherwise use in an automotive situation. Why 5 wires you ask? 5vdc in, baro-out, MAP-out, ground to ECU, local ground to chassis.
Another consideration for this would be that the two sensors are actually meant to be part of a sealed module and as such do not have barbed hose fittings so any hose attached may be prone to falling off. Solutions for this could be either chemical bonding or spin-welding a proper hose fitting to them, or having a bulk-head fitting directly over the inlet that holds a small section of hose/pipe securely to the sensor and also which exposes a barbed port externally; in particular the 6400, if it's used with a forced-induction engine, would require something for a better, mechanical connection.
Similarly, if not being used for forced induction, a 6115 could be used for MAP. One benefit of this is there are 3v3 versions of the 6115 available, and as such would be a better fit for many microcontrollers, making any op-amp configuration only require be to install resistors which configure it for unity-gain / buffer.
You can lead the horticulture but you can't make them think.