As mentioned before I made a few mistakes on the first revision of the Quadcopter controller board. Although I was able to modify it and get it up and running, I decided to spin another board and do a second revision to fix the things I learned with the first revision.
The changes on this revision include:
- Change the 5V Regulator (U3) to a TO-220 package LM7805
- Increase the hole size on the power connection since the wire I used wouldn’t fit.
- Change the Accelerometers from the Invensense IDG-500 and ISZ-500 analog to the Invensense ITG-3200
- Change the Gyroscope from the Analog Devices ADXL 335 Anaglog gyroscope to the ADXL 345 Digital gyroscope
- Since the sensors are digital I was also able to remove the precision voltage reference for the ADC.
- I also fixed up the footprint on the compass. The newer version of the datasheet for the HMC5883 said that it required that no power traces run underneath the chip and that there in no copper planes underneath so I have removed both.
- I removed the level shifter on the PWM lines that control the motors since I found that the ESCs would work with 3.3V logic.
- I also added a few more testpoints and an LED that is controlled by the microcontroller
Once I build up the new boards I will post picture of the new board built up but here is a picture of thelayout an the schematics:
Schematic
Quadcopter Controller R1.0
Andrew