What this optocoupler does in the assembly
The Renesas PS9513-AX is a single-channel optocoupler with an open-collector output, designed to pass a DC logic-level signal across a 5000Vrms isolation barrier at up to 1Mbps. It fits applications like PLC digital inputs, motor-drive fault feedback, and isolated communication links where the receiving side needs a pull-up to a supply rail between 4.5V and 20V. The through-hole 8-DIP package suits boards that see rework or where a hand-solderable footprint is preferred over a surface-mount part.
At 1Mbps this part handles typical fieldbus rates for Modbus RTU, Profibus DP, and general-purpose isolated UART links. The open-collector output with a max propagation delay of 750ns (tpLH) and 500ns (tpHL) gives enough margin for a 1Mbps bit cell (1 µs) when the pull-up resistor is sized for the bus capacitance. The 15kV/µs common-mode transient immunity means the output stays clean when a motor drive or inverter switches a high-voltage rail — a spec that matters more than the data rate in noisy industrial environments.
Through-hole DIP: rework-friendly but plan the pad layout
The 8-DIP (0.300" row spacing, 7.62mm pitch) is a standard footprint that any through-hole soldering station handles. No thermal pad, no hidden leads — lift the part, not the pad, if a rework cycle comes. The 15 mA per-channel output current is enough to drive a logic input or a small relay coil through a transistor; for heavier loads, buffer it. The forward voltage is 1.65V typical, so a 3.3V or 5V logic rail drives the LED side directly with a series resistor sized for the 25mA max If.