5000Vrms isolation and 250ns switching for high-speed signal isolation
The onsemi HCPL4503SM is a single-channel optoisolator with a transistor-with-base output, rated for 5000Vrms isolation — enough for reinforced insulation in mains-connected circuits like PLC digital inputs, motor drive feedback, and medical patient-interface barriers. Typical turn-on and turn-off times of 250 ns and 260 ns respectively make it fast enough to pass 1 MHz logic signals cleanly, suiting it for high-speed data isolation in industrial fieldbus couplers or gate-drive feedback paths.
CTR range and output drive — design margin for aging
Current transfer ratio spans 19% minimum to 50% maximum at a forward current of 16 mA — the wide guard band between min and max lets the designer account for LED degradation over temperature and lifetime without losing logic threshold. Output is rated for 8 mA continuous at 20 V max, which drives standard TTL or 5 V CMOS loads directly; the base terminal allows external pull-up or speed-up networks for custom switching thresholds.
Surface-mount package and industrial temperature grade
Housed in an 8-pin SMD gull-wing package (8-SMD), the HCPL4503SM reflows with standard lead-free profiles and requires no through-hole staking — a drop-in for automated assembly lines.
Active lifecycle and compliance — no obsolescence risk
No stock-holding claim — availability verified per request.