Vishayisocom transistordarlington output optoisolators toshiba tlp620 4 quad transistor output optoisolator consisting of a phototransistor optically coupled to 2 gaas infrared emitting diode connected in inverse parallel provides 4 isolated channels in a sixteen plastic dip can be used with programmable controllers acdc input modules and telecommunications toshiba tlp620 4 quad transistor optoisolator