BF556B,215

Overview

The BF556B is an N-channel symmetrical silicon junction field-effect transistor housed in a SOT23 plastic surface-mounted package. It features a drain-source voltage rating of ±30 V and a total power dissipation of 250 mW at 25 °C ambient temperature. The device exhibits a forward transfer admittance of at least 4.5 mS. For the BF556B variant, the drain current (IDSS) ranges from 6 mA to 13 mA when VGS is 0 V and VDS is 15 V. The gate-source cut-off voltage (VGSoff) spans from -0.5 V to -7.5 V under specified conditions.

Feature Summary

• Low leakage level
• High gain
• Low cut-off voltage

Applications

• Impedance converters in electret microphones
• Impedance converters in infrared detectors
• VHF amplifiers in oscillators
• VHF amplifiers in mixers

Procurement Notes

Verify the specific part number suffix against official documentation to confirm manufacturing origin and compliance status. Confirm that the component matches the required pinout and marking codes for integration. Ensure handling procedures account for ElectroStatic Discharge sensitivity during transport and assembly. Validate that the sourcing channel provides authentic product data sheets consistent with NXP Semiconductors specifications.

Selection Notes

Select the BF556B when application requirements specify a drain current range between 6 mA and 13 mA at zero gate-source voltage. Consider this device for circuits requiring low cut-off voltages and high gain characteristics. Evaluate thermal resistance constraints, as the junction-to-ambient thermal resistance is 500 K/W. Ensure the design accommodates the ±30 V drain-source voltage limit and the 250 mW power dissipation capability.

Part Context

The BF556B belongs to the BF556A, BF556B, and BF556C series of N-channel silicon junction field-effect transistors. These components share identical physical packaging and general electrical limits but are distinguished by their specific drain current and cut-off voltage parameters. The series is designed for applications demanding symmetrical operation and low noise performance in small form factors.

Replacement Considerations

BF556A and BF556C are documented variants within the same family. Substitution requires verification that the alternative's drain current and cut-off voltage parameters align with the circuit design requirements.