The IL74/ ILD74/ ILQ74 is an optically coupled pair with a GaAIAs infrared LED and a silicon NPN photo-transistor. Signal information, including a DC level, can be transmitted by the device while maintaining a high degree of electrical isolation between input and output.
The IL74/ILD74/ILQ74 family are optically coupled devices with a GaAlAs infrared LED and a silicon NPN phototransistor, intended for medium‑speed logic isolation, ground‑loop elimination, and replacement of relays or transformers in digital and analog applications.
The datasheet lists features, absolute maximum ratings, electrical characteristics, switching performance, package dimensions, and regulatory approvals, along with ordering options and legal notices.
| Typical Transfer Ratio | 35 % (typical) |
|---|---|
| Coupling Capacitance | 0.5 pF |
| Input Forward Continuous Current | 60 mA |
| Input Peak Reverse Voltage | 3.0 V |
| Collector‑Emitter Breakdown Voltage | 20 V |
| Isolation Test Voltage (1 s) | 5300 V |
| Package Power Dissipation (IL74) | 200 mW |
| Storage Temperature Range | -55 °C to +150 °C |
| Operating Temperature Range | -55 °C to +100 °C |
The typical current transfer ratio is 35 % for the IL74/ILD74/ILQ74 devices.
It is rated for an isolation test voltage of 5300 V for a 1‑second duration.
The maximum continuous forward current is 60 mA.
IL74 is offered in a single‑channel DIP‑6, ILD74 in a dual‑channel DIP‑8, and ILQ74 in a quad‑channel DIP‑16, with additional SMD options.