QT852

Overview

The QT852 is a high-power photodarlington optoisolator manufactured by QT Brightek (QTB). It features a single channel with DC input and transistor output, housed in a 4-DIP package. The device provides an isolation voltage of 5000Vrms and operates within a temperature range of -55°C to 100°C. Key electrical characteristics include a maximum current transfer ratio of 15000% at 1mA input current, with typical rise and fall times of 250µs and 95µs respectively. It is designed for applications requiring robust signal isolation and high gain.

Feature Summary

• High isolation voltage capability between input and output circuits
• Darlington transistor output configuration for high current gain
• Wide operating temperature range suitable for industrial environments

Applications

• Industrial control systems requiring galvanic isolation
• Power supply feedback loops
• Signal transmission across isolated grounds

Procurement Notes

Verify the specific datasheet version and mechanical dimensions against your PCB layout requirements. Confirm that the 4-DIP package spacing matches your footprint. Ensure the thermal management strategy accommodates the power dissipation characteristics under maximum load conditions. Check for RoHS compliance status if required by your manufacturing standards.

Selection Notes

Select this component when high current transfer ratio is critical for driving loads directly from the output side. The Darlington configuration offers significant amplification compared to standard transistor outputs. Consider the slower switching speeds inherent to Darlington structures when designing for high-frequency applications. Verify input current limits to ensure proper LED drive conditions.

Part Context

This part belongs to the optoisolator category, specifically utilizing a photodarlington output structure. It serves as a bridge for transferring digital or analog signals between electrically isolated circuits. The 4-pin DIP format facilitates through-hole mounting on printed circuit boards. It is distinct from photovoltaic or logic-output isolators due to its specific gain and speed characteristics.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.