Multiple sensors. I need help with schematic

Projects General Guidance
1

For the first time, I am creating a schematic for a biofeedback device I will be working on. So far my device has a temperature sensor and pulse sensor that will display both output on the 16x2 LCD. I also have an EMG sensor that will be an auditory feedback. I have a pushbutton so that when pushed down, it uses the body temperature sensing function, when pushed again it does the pulse sensor, and when pushed again it uses the EMG sensor.

While creating the schematic, it made me realize that I don't know a lot and I have more to learn about.

I have looked into the data sheet of each of my sensor and the LCD. All i understood is that:

  1. the temp sensor (LM35) operates from 4V to 30V
  2. pulse sensor only states that it can be plugged in into a 3 or 5V on arduino (lacks datasheet) link of pulse sensor Pulse Sensor - SEN-11574 - SparkFun Electronics
  3. similar to the pulse sensor, EMG sensor states that it can be plugged into the 3.3V or 5V on arduino https://media.digikey.com/pdf/Data%20Sheets/Sparkfun%20PDFs/MyoWare_Muscle_Sensor_Kit_Guide.pdf

I wanted some help to look at my schematic to see if I am doing connections correctly. It doesn't seem right to me that all my sensors, LCD, 3.5mm jack are all connected to the 5V from Arduino. I considered that doing this, it might fry up the Arduino :confused:

I have read that I might need to use an external power for sensors but I am not completely sure how to implement that to my circuit.

Please enlighten me if you see any mistakes.

Thank you very much!!!

-L

biofeedback schematic.JPG
biofeedback schematic.JPG734×494 70.1 KB

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You need to know the current consumption of Your sensors and the LCD. How do You intend to power the Arduino? The Arduino has some +5 outlets but You must not exceed the capability of the Arduino if You want to power Your sensors that way and the Arduino is powered by the 7 - 12 volt plug. If the Arduino is powered via the USB plug things look easier.