J509 TO-92 2L

Current Regulation - Diodes, Transistors Overview

The Linear Integrated Systems J509 is a two-lead current regulator diode designed for constant-current supply and current-limiting applications. It utilizes JFET techniques to maintain stable operation within a ±20% tolerance range. The device supports voltages up to 50V and operates across a temperature range of -55°C to 150°C junction temperature. Key electrical parameters include a forward current of 2.4mA (nominal), dynamic impedance of 0.09Ω, and knee impedance limiting voltage of 3.5V. It features excellent temperature stability and high circuit stability versus temperature.

Current Regulation - Diodes, Transistors Feature Summary

• Two-leaded plastic package design simplifies series circuitry without requiring separate voltage sources
• Utilizes JFET techniques to ensure tight guaranteed circuit performance and excellent temperature stability
• Provides high circuit stability versus temperature variations

Current Regulation - Diodes, Transistors Applications

• Constant-current supply circuits
• Current-limiting protection
• Timing circuits
• Low-voltage battery circuits
• High-voltage spike protection

Current Regulation - Diodes, Transistors Procurement Notes

Verify the specific manufacturer origin as Linear Integrated Systems or Micross Components, noting that Linear Systems replaced the discontinued Siliconix J500 line. Confirm the TO-92 package configuration matches the two-leaded requirement. Ensure the component meets the specified ±20% tolerance and 50V maximum operating voltage requirements for your application environment.

Current Regulation - Diodes, Transistors Selection Notes

Select the J509 when a nominal 2.4mA regulation current is required. Verify that the load voltage remains below the 50V absolute maximum rating. Consider the TO-92 package constraints for thermal management given the 150°C junction temperature limit. Ensure the application benefits from the simple two-terminal interface rather than complex biasing networks.

Current Regulation - Diodes, Transistors Part Context

The J509 belongs to the J500 series of current regulator diodes originally developed by Siliconix and later continued by Linear Integrated Systems. This series replaces older discrete solutions with integrated JFET-based regulators. The J509 specifically offers a higher current rating compared to lower-end models in the series, suitable for moderate current demands in instrumentation.

Current Regulation - Diodes, Transistors Replacement Considerations

The J509 serves as a direct replacement for the discontinued Siliconix J509. Verify pinout compatibility if substituting with other generic current regulator diodes, as the two-leaded TO-92 format is standard but internal configurations may vary between manufacturers.