The IL300 linear optocoupler consists of an AlGaAs IRLED
irradiating an isolated feedback and an output PIN
photodiode in a bifurcated arrangement. The feedback
photodiode captures a percentage of the LEDs flux and
generates a control signal (IP1) that can be used to servo the
LED drive current. This technique compensates for the
LEDs non-linear, time, and temperature characteristics.
The output PIN photodiode produces an output signal (IP2)
that is linearly related to the servo optical flux created by the
The time and temperature stability of the input-output
coupler gain (K3) is insured by using matched PIN
photodiodes that accurately track the output flux of the LED.