SparkFun Electronics Forum

Hi. I am trying to build a custom sensor board to connect several sensors to Atmega328p microcontroller.

If anyone can help me and look to the schematics, maybe point some errors, I would really appreciate it.

It is ADXL345 connected to Atmega328p, also a slot for DS18B20 digital thermometer. I have several pads connected to control LEDs with PWM and one pad for interrupt input.

No decoupling caps.

Where does "Res" go thats on R2? I cannot see another reference to it.

mattylad wrote:Where does "Res" go that's on R2? I cannot see another reference to it.

RES goes to C2. According to its datasheet,the ADXL345 can't have more than 3.9v max on its pins. The micro is a 5 volt part, so its output HI voltage (logic '1') will be 5 volts. The ADXL345 will be damaged or destroyed by connecting its pins directly to the micro. Can you lower the micro's power supply to 3.3volts?

So it does, if its only there why not simply connect it up lol