SFH6345

Overview

The SFH6345 is a high-speed optocoupler featuring a GaAlAs infrared emitting diode optically coupled to an integrated photodetector. It supports data transmission rates up to 1 Mbps and offers a common-mode rejection of 15 kV/µs. The device provides electrical isolation with a rated insulation voltage of 5300 Vrms. Key electrical parameters include a maximum forward current of 25 mA, a typical forward voltage of 1.33 V, and a reverse voltage rating of 3 V. The output stage delivers a collector current of 8 mA with a saturation voltage of 400 mV. The current transfer ratio is specified at a minimum of 19% when driven at 16 mA. Operating temperatures range from -55°C to +100°C.

Feature Summary

• High-speed signal transmission capability supporting up to 1 Mbps data rates
• Integrated photodetector combining a photodiode and high-gain transistor for enhanced performance
• Robust electrical isolation with a 5300 Vrms insulation voltage rating
• High common-mode noise immunity characterized by a 15 kV/µs rejection rate

Applications

• Industrial communication interfaces requiring galvanic isolation
• Signal coupling in noisy electromagnetic environments
• Microcontroller-to-peripheral interface isolation
• Power supply feedback loop isolation

Procurement Notes

Verify the specific suffix code (e.g., X016 for PDIP-8 or X019T for SMD-8) to ensure correct package type and lead frame material. Confirm RoHS compliance status and moisture sensitivity level requirements against project specifications. Cross-reference the datasheet revision number to ensure alignment with latest electrical characteristics and mechanical dimensions before finalizing procurement orders.

Selection Notes

Select this component for applications demanding high-speed digital isolation with moderate current drive capabilities. The integrated detector design offers superior speed compared to standard phototransistor-only couplers. Ensure the input current does not exceed the 25 mA maximum limit. Verify that the required isolation voltage meets the system safety standards, as the 5300 Vrms rating provides significant margin for many industrial applications.

Part Context

This device belongs to the SFH6345 series of high-speed optocouplers manufactured by Vishay Semiconductor Opto Division. The series utilizes GaAlAs technology for efficient infrared emission. Variants within the family differ primarily in packaging options, such as through-hole DIP or surface-mount configurations, while maintaining consistent core electrical performance and isolation characteristics across the product line.

Replacement Considerations

Direct pin-compatible alternatives may include other high-speed optocouplers from Vishay or competitors offering similar 1 Mbps speeds and 5300 Vrms isolation. Verify that substitute parts match the 15 kV/µs common-mode rejection requirement and the 8 mA output current capability. Check if the replacement uses the same GaAlAs LED technology to ensure comparable switching times and temperature stability.