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Questions relating to designing PCBs
By re4mat0r
#190315
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.
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By davep238
#190394
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?