Datasheet

There is no simple way to isolate an analog signal without converting it to something else;
this isolator uses pulse width modulation (PWM) to encode the analog pH readings.
The output of the analog isolator is a 10.6 Khz square wave. No matter what the reading
is, the frequency is always 10.6 kHz. The data is encoded in the width of each square wave,
PWM (pulse width modulation).
*
The frequency is always 10.6 kHz; it is only the width of each pulse that changes.
Example PWM Example Voltage
pH 4
pH 7
pH 10
Operating principle
PWM
Generator
Voltage
Isolator
Opto-Isolator
Block diagram of the analog isolator
3 Volts
1.5 Volts
0 Volts
pH 7
3 Volts
1.5 Volts
0 Volts
pH 10
3 Volts
1.5 Volts
0 Volts
pH 4