IL251

Transistor, Photovoltaic Output Optoisolators Overview

The IL251 is a single-channel transistor output optocoupler manufactured by Vishay Semiconductor Opto Division. It features bidirectional AC input capability with built-in reverse polarity protection, eliminating the need for external diodes. The device provides high isolation voltage of 5300 Vrms and operates within a temperature range of -55°C to +100°C. Key electrical parameters include a maximum forward current of 60 mA, a maximum forward voltage of 1.5 V, and a minimum current transfer ratio of 20%. It utilizes a through-hole DIP-6 package.

Transistor, Photovoltaic Output Optoisolators Feature Summary

• Bidirectional input design supporting AC or polarity-insensitive signals
• Integrated reverse polarity protection on the input side
• High insulation voltage rating for robust circuit isolation
• Improved current transfer ratio symmetry for consistent performance

Transistor, Photovoltaic Output Optoisolators Applications

• Industrial control systems requiring reliable signal isolation
• Power supply feedback loops with AC input characteristics
• Solid-state relay driver circuits
• Microcontroller interface isolation for noisy environments

Transistor, Photovoltaic Output Optoisolators Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm package type matches DIP-6 requirements. Check datasheet revisions for any updates regarding RoHS compliance status, as historical data indicates non-compliance in some contexts. Ensure storage conditions align with moisture sensitivity levels if applicable. Validate supplier documentation against official Vishay specifications before procurement.

Transistor, Photovoltaic Output Optoisolators Selection Notes

Select the IL251 when bidirectional input functionality is required without additional external components. Consider its high isolation voltage for applications demanding significant potential difference between input and output circuits. Evaluate the minimum 20% current transfer ratio against load requirements. Compare thermal dissipation limits against expected operating temperatures. Choose this part over standard optocouplers where AC input compatibility simplifies circuit design.

Transistor, Photovoltaic Output Optoisolators Part Context

The IL251 belongs to the IL25x family of single-channel optocouplers from Vishay. It shares architectural similarities with the IL250 and IL252, differing primarily in current transfer ratio selection. The family includes dual-channel variants like the ILD251. These devices are designed for general-purpose isolation tasks, offering industry-standard packaging and proven reliability in industrial and commercial electronics applications.

Transistor, Photovoltaic Output Optoisolators Replacement Considerations

Direct substitutes include IL250 and IL252 from the same Vishay series, which share identical pinouts and mechanical dimensions but differ in current transfer ratio specifications. Verify that alternative parts meet the specific CTR requirements of the application. Cross-reference datasheets to ensure compatibility with existing PCB layouts and thermal management strategies.