15 Mbps open-collector optocoupler for industrial isolation
The Renesas PS9821-1-F3-AX is a single-channel, DC-input optocoupler from the NEPOC series with an open-collector output rated for 15 Mbps data rate and 2500 Vrms isolation. Key distinguishing features include a 15 kV/µs common-mode transient immunity (CMTI) and symmetrical 75 ns max propagation delays (tpLH / tpHL), making it suited for isolating high-speed digital signals in noisy industrial environments such as PLC I/O modules, motor drive interfaces, and fieldbus communication links.
Data rate of 15 Mbps supports Profibus, DeviceNet, and other industrial fieldbuses running at 12 Mbps or lower. The open-collector output requires an external pull-up resistor to the receiver's supply rail; the 25 mA per-channel output current drives standard logic families or small relays directly. Isolation rating of 2500 Vrms covers basic insulation for 240 VAC mains-powered equipment. The 15 kV/µs CMTI ensures the output stays clean when the input side experiences fast voltage transients from IGBT switching or relay coil kickback — a common failure point in motor drives and inverters. Forward voltage (Vf) typical 1.65 V with a 20 mA max forward current means the LED side can be driven directly from a 3.3 V logic output through a current-limiting resistor. Rise/fall times of 20 ns and 5 ns respectively, combined with the 75 ns propagation delay, give enough timing margin for most 15 Mbps NRZ serial links. The 8-SSOP package (0.154" body width) saves board space compared to DIP-8 optocouplers.
Active lifecycle — no EOL risk for new designs
This part is suitable for both new design-ins and ongoing production builds without supply-chain disruption.