Isolation barrier and signal transfer
The CNY174 provides 5300Vrms galvanic isolation between input and output, certified for safety barrier applications in industrial controls, PLCs, and power supply feedback loops where the primary-to-secondary isolation voltage must withstand transient overvoltages per IEC 60950-1 reinforced insulation requirements. Current transfer ratio spans 160% minimum to 320% maximum at 10mA forward current, giving the designer a guaranteed gain window for logic-level translation — a CTR floor of 160% ensures the output transistor saturates with standard TTL or CMOS input thresholds even with LED aging or temperature drift. Switching timing is specified at 1µs rise and 2µs fall typical, with turn-on at 2µs and turn-off at 3µs — fast enough for 100kHz PWM isolation or serial data at moderate baud rates, but not suited for high-speed digital buses where digital isolators with 100Mbps data rates are required.
Output drive and temperature range
Output transistor handles up to 70V collector-emitter voltage and 50mA continuous current per channel — enough to drive a relay coil, a logic gate input, or a small DC load directly without a buffer transistor. Operating temperature covers -55°C to 100°C, placing it in the industrial temperature grade — suitable for motor drive cabinets, telecom outdoor enclosures, and factory floor panels where ambient heat and cold start are design constraints. Vce saturation is clamped at 300mV maximum, keeping the output voltage drop low when the transistor is fully on — important for maintaining logic-low levels below 0.8V in TTL-compatible circuits.
Housed in a 6-DIP through-hole package with 0.300-inch (7.62mm) body width and standard 2.54mm pin pitch — the same footprint as industry-standard dual-in-line optocouplers, allowing drop-in replacement on existing PCB layouts without board spin. Through-hole mounting suits prototype builds, rework-friendly designs, and high-vibration environments where a soldered lead provides stronger mechanical retention than surface-mount packages. Supplied in tube packaging — the standard anti-static tube for DIP devices, compatible with automatic insertion equipment and manual assembly.
Available through independent distribution channels as new-old-stock or surplus inventory. Each lot is sourced and quoted against an RFQ, with traceability and authenticity verified before shipment. For BOM positions requiring this exact isolation rating and CTR window, the obsolete status means the part is a single-source line item — no pin-compatible replacement from onsemi is documented, so board-level qualification of any alternative is the buyer's responsibility.