onsemi FOD8802 OptoHiT™ Phototransistor Optocouplers utilize onsemi’s leading-edge proprietary process technology. This achieves a high operating temperature performance of up to 125°C. The optocouplers consist of two aluminum gallium arsenide (AlGaAs) infrared light-emitting diodes optically coupled to two phototransistors. They are housed in a small outline, 8-pin SOIC package. The devices deliver a consistent current transfer ratio at a very low input current over temperature.