BSR56

Overview

The BSR56 is an N-channel Junction Field-Effect Transistor (JFET) designed for low-power chopper or switching applications. It operates within a Drain-Gate Voltage of 40 V and a Gate-Source Voltage of -40 V, with a total power dissipation of 250 mW up to 40°C ambient temperature. The device features a Gate-Source Cut-off Voltage ranging from 4 V to 10 V and a Drain-Source On Reverse resistance of 25 Ω at zero gate voltage. Electrical characteristics include a maximum Zero-Gate Voltage Drain Current of 50 mA and a reverse transfer capacitance of 5 pF. The component supports junction temperatures up to 150 °C and storage ranges from -55 °C to 150 °C.

Feature Summary

• Designed specifically for low-power chopper and switching applications sourced from process 51
• Provides low-frequency low-noise amplification capabilities in an N-channel configuration
• Features fast switching performance with defined delay, rise, and turn-off times

Applications

• Low-power chopper circuits
• Switching applications
• Low-frequency low-noise amplifiers

Procurement Notes

Verify the current ordering designation on the official manufacturer website before purchasing. Due to the integration of Fairchild Semiconductor into ON Semiconductor, legacy part numbers containing underscores may have been updated to use dashes. Confirm that the specific package variant matches the required SOT-23 form factor and ensure compliance with RoHS standards applicable to the target region.

Selection Notes

Select this component when designing circuits requiring low-noise amplification or precise switching at low frequencies. Ensure the application stays within the 250 mW power dissipation limit at ambient temperatures above 40°C by implementing appropriate thermal management. Verify that the required Gate-Source Cut-off Voltage falls within the specified 4 V to 10 V range for the intended biasing conditions.

Part Context

The BSR56 belongs to the JFET category of discrete semiconductors, historically manufactured by Fairchild Semiconductor before its acquisition by ON Semiconductor. It utilizes the SOT-23 surface-mount package, providing a compact footprint suitable for portable and space-constrained electronic designs. The device represents a transition point in the manufacturer's portfolio following corporate restructuring.

Replacement Considerations

Consult the official ON Semiconductor database for direct equivalents, as legacy Fairchild part numbers may require suffix updates. When substituting, verify that the replacement JFET maintains compatible Drain-Source On Reverse resistance and Gate-Source Cut-off Voltage specifications to ensure circuit stability.