Four-channel isolation in a single SOIC
The Renesas PS2801C-4-F3-A is a 4-channel phototransistor optocoupler providing 2500 Vrms of galvanic isolation between a DC input LED and a transistor output. With a current transfer ratio (CTR) guaranteed between 50% and 400% at 5 mA forward current, it is designed for logic-level interfacing, PLC I/O modules, and isolated sensor feedback in industrial and telecom equipment.
CTR spread and drive margin
The 50% to 400% CTR range at 5 mA is the headline design parameter. A minimum CTR of 50% means the output transistor will saturate with as little as 5 mA LED drive, but the 8:1 spread means the actual gain varies widely across units. For a 5 V logic-level shift, the typical forward voltage is 1.2 V, and the output can sink up to 30 mA per channel at a maximum Vce saturation of 300 mV. The 80 V output rating gives headroom for 24 V or 48 V industrial buses. Rise time is 5 µs, fall time 7 µs, turn-on 10 µs, turn-off 7 µs.
Package and footprint
The part is offered in a 16-SOIC (0.173", 4.40 mm width) package, with the supplier device package listed as 16-SSOP. The 4-channel layout consolidates four optocouplers into one IC, saving board area versus four single-channel parts in SOIC-4 or DIP-4 packages.
