Optocoupler ORPC817SC

Updated: 2026-07-18

Overview

The ORPC817SC is a widely used photocoupler that consists of an infrared LED optically coupled to a phototransistor. This device provides electrical isolation between input and output circuits while allowing signal transmission through light. As a fundamental component in many electronic systems, the ORPC817SC helps prevent noise transmission and protects sensitive components from voltage spikes. Its compact DIP-4 package makes it suitable for various PCB designs.

Structure and Working Principle

The ORPC817SC contains two main components: a GaAs infrared LED and a silicon phototransistor. When current flows through the LED, it emits infrared light that activates the phototransistor on the output side. This optical coupling method ensures complete electrical isolation between input and output circuits, typically providing isolation voltages of 5kV or more. The device operates without any physical connection between the circuits it separates.

Key Features

The ORPC817SC offers several important characteristics including high isolation voltage (typically 5kV rms), current transfer ratio (CTR) ranging from 50% to 600%, and fast response times. Additional features include wide operating temperature range (-55°C to +110°C), compact DIP-4 package, and compliance with various international safety standards. These characteristics make it versatile for different industrial applications.

Application Areas

This photocoupler finds extensive use in power supply feedback circuits, industrial control systems, and communication equipment where signal isolation is critical. Other common applications include microprocessor interface circuits, medical equipment, and home appliances. It's particularly valuable in situations requiring protection against high voltage transients or electrical noise.

Maintenance and Precautions

When using the ORPC817SC, avoid exceeding the absolute maximum ratings for input current, power dissipation, and isolation voltage. Proper PCB layout is important to maintain isolation performance. Storage should be in dry conditions below 40°C with relative humidity under 70%. During soldering, follow recommended temperature profiles to prevent damage to the plastic package.

B2B Procurement Guide

For bulk purchases, verify the manufacturer's authenticity as counterfeit components are common in the market. Consider ordering samples for testing before large-scale procurement. Key specifications to confirm include current transfer ratio range, isolation voltage rating, and package type. Lead time typically ranges from 4-8 weeks for large orders, so plan accordingly.