jaypeche / ec-ph-temperature-shield Goto Github PK

EC, pH and temperature shield for arduino.

The pH sensor is inspired from phDuino. It is composed by an amplifier and a 2nd order low-pass filter (Rauch) The amplifier is designed to span the input range of a typical pH probe (-400 -> 400 mV) to the input range of an arduino ADC (0 -> 5V). pH = 0 gives 2.5V.

The EC sensor is composed by 3 main structures:

• A 2nd order low pass-filter (Rauch) in order to convert the PWM input into a +-200mV sin wave.
• A trans-impedance amplifier
• A crete detector.

The temperature sensor is just a 1-wire temperature sensor (DS18B20).