PC123

Overview

The PC123 is a single-channel transistor output optocoupler manufactured by Sharp Microelectronics. It features an infrared emitting diode optically coupled to an NPN phototransistor within a 4-pin DIP package. The device provides an isolation voltage of 5000 Vrms and supports a collector-emitter voltage of up to 70 V with a maximum collector current of 50 mA. Current transfer ratios range from 50% to 400% at an input current of 5 mA. Typical switching times include a rise time of 4 µs and a fall time of 3 µs. Operating temperatures span from -30°C to +100°C.

Feature Summary

• High isolation voltage capability for safe signal transmission between circuits
• Wide current transfer ratio range allowing flexible gain selection
• Reinforced insulation design with long creepage distance options

Applications

• Microcontroller unit I/O isolation
• Noise suppression in switching circuits
• Signal transmission between circuits with different potentials and impedances
• Overvoltage detection systems

Procurement Notes

Verify the specific suffix code on the component marking, as variations exist regarding lead spacing and packaging format. Confirm RoHS compliance status, as older production runs may not meet current environmental directives. Check availability carefully since this model is listed as obsolete or NRND in many distributor catalogs. Ensure the selected variant matches the required thermal and electrical specifications for the target application environment.

Selection Notes

Select variants based on required creepage distance and package type, such as wide-lead DIP or SMT gullwing configurations. Consider the specific CTR bin required for the circuit design, as ratios vary significantly between 50% and 400%. Verify that the 5000 Vrms isolation rating meets the safety standards of the end equipment. Ensure the operating temperature range covers the intended environmental conditions.

Part Context

This component belongs to the Sharp PC123 series of optocouplers, which are designed for general-purpose isolation applications. The series utilizes a dual-injection molding process for enhanced durability and reliability. These devices are widely recognized for their robust construction and compliance with European safety standards. The family includes various pin spacing and mounting options to accommodate diverse PCB layout requirements.

Replacement Considerations

Direct replacements should be sought from the same Sharp PC123 series with matching suffix codes. Verify that substitute components maintain the 5000 Vrms isolation rating and similar CTR ranges. Cross-reference pinouts and package dimensions to ensure mechanical compatibility without redesigning the footprint.