in this video we'll look at how to design a breakout board from scratch in keycad for a differential pressure sensor combined with an stmNUMBER_TOKEN microcontroller we can use a differential pressure sensor on a drone for example to measure airspeed which in turn can be used for a closed-loop airspeed control system the differential pressure sensor measures static and dynamic pressure by a pitot-static tube and from the difference of these pressures we can estimate the aircraft's airspeed i'll leave a link in the description for further information on how this works and we'll also make a follow-up video for the software part of this board thank you to jlc pcb for sponsoring this video i had these breakout boards manufactured and assembled by them you can go to URL_TOKEN pmsNUMBER_TOKEN and look up the airspeed sensor board repository to find all design files manufacturing files and assembly files so you can order these boards from jlc pcb yourself alternatively i've recently launched a new phil's lab website at URL_TOKEN which includes a webshop where you can get fully assembled and tested boards shipped straight to you the links for this are in the description box below as usual another thank you to altium for sponsoring this video in my previous video i showed how to use altium designer to design a similar breakout board for an inertial measurement unit if you visit URL_TOKEN yt phil's lab you can check out autumn designer for yourself using their free trial i'll be featuring more of altum designer in upcoming videos on fpga design so stay tuned but for now let's get started with the keycad and this breakout board the main parts that i'm using for this design are found in the glc pcb parts library firstly the differential pressure sensor is through-hole and actually not that inexpensive we'll need the datasheet for the footprint information also at the programming stage in a later video then we also have the stmNUMBER_TOKEN microcontroller which is this very simple stmNUMBER_TOKENfNUMBER_TOKEN and this is very inexpensive but sufficient for this design and it serves a couple of purposes one is to read the differential pressure sensor data by i squared c then to filter that raw sensor data and convert it to an airspeed in meters per second squared measurement and lastly to provide the filter data to a master via spi including a data ready interrupt pin so let's move over to keycard and look at the schematic here i am in keycard looking at the finished schematic for this board there are roughly three sections first of all the power supply over here the microcontroller and sensor over here as well as the i o connector let's go through them one by one the power supply is fed by a plus five volt source provided to the board passes through a schottky diode for reverse polarity protection and goes into a low dropout or ldo regulator this steps the input voltage down to NUMBER_TOKEN volts which is used by the stmNUMBER_TOKEN and the sensor since this is a fairly low power design an ldo is more than sufficient and a diode good enough for protection the ldl requires an input as well as an output capacitor for stability of at least one microfarad which is stated in the datasheet but i've opted for larger NUMBER_TOKEN microfarad
START_SPONSOR_TOKEN thank you to jlc pcb for sponsoring this video i had these breakout boards manufactured and assembled by them you can go to URL_TOKEN pmsNUMBER_TOKEN and look up the airspeed sensor board repository to find all design files manufacturing files and assembly files so you can order these boards from jlc pcb yourself END_SPONSOR_TOKEN BETWEEN_SEGMENTS_TOKEN START_SPONSOR_TOKEN as usual another thank you to altium for sponsoring this video in my previous video i showed how to use altium designer to design a similar breakout board for an inertial measurement unit if you visit URL_TOKEN yt phil's lab you can check out autumn designer for yourself using their free trial i'll be featuring more of altum designer in upcoming videos on fpga design so stay tuned but for now let's get started with the keycad and this breakout board END_SPONSOR_TOKEN