NXP Semiconductors BF510,215

Overview

BF510,215 from NXP Semiconductors is an asymmetrical N-channel planar epitaxial junction field-effect transistor (JFET) in SOT23 package, designed for RF amplification up to VHF range. It delivers IDSS > 0.7 mA, yfs > 2.5 mS at 1 kHz, Crs = 0.3 pF (typ), F = 1.5 dB (typ) at 100 MHz, and operates with VDS ≤ 20 V - making it ideal for RF front-end stages in FM portable radios.

For engineers reviewing the BF510,215 datasheet, BF510,215 pinout, BF510,215 application, or BF510,215 equivalent, key selection criteria include low-noise RF gain, ultra-low feedback capacitance, gate-source cutoff voltage of −V(P)GS ≈ 0.8 V (typ), thermal resistance Rth j-a = 430 K/W, and compatibility with hybrid thick/thin-film circuit assembly.

Technical Context

The BF510,215 operates as a depletion-mode N-channel JFET with fixed gate bias via zero-VGS operation. Its asymmetrical structure optimizes high-frequency performance by minimizing Crs and maximizing yfs at 100 MHz (3.5 mS typ), while maintaining low noise figure under matched source admittance (GS = 1 mS, −BS = 3 mS).

It is characterized under VDS = 10 V, VGS = 0 for static parameters and uses common-source configuration for dynamic measurements. Thermal derating begins above Tamb = 40 °C, with Ptot linearly reduced to zero at 160 °C per the published power derating curve.

Key Specifications

Pinout & Package

BF510,215 is housed in the SOT23 (TO-236AB) plastic surface-mounted package - a 3-lead miniature outline measuring 2.9 mm × 1.3 mm × 1.0 mm (L × W × H), optimized for high-density RF hybrid circuits.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar RF JFET amplifier applications.

Compared with BF511,215 and 2N5484, the BF510,215 offers the lowest IDSS and smallest Crs in the BF510–513 family - making it uniquely suited for low-current, ultra-stable VHF amplifiers where bias stability and minimal parasitic coupling are critical.

Availability

BF510,215 is available at Aetrix Electronics and suitable for FM portable radios, automotive infotainment RF front-ends, and hybrid thick-film communication modules requiring stable component supply and long-lifecycle support.

Supply support for BF510,215 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor company delivering high-performance mixed-signal and standard products, with leadership in RF, analog, and interface technologies.

The BF510,215 belongs to NXP's legacy RF JFET product line, engineered specifically for low-noise, high-frequency amplification in consumer audio and broadcast receivers - emphasizing manufacturability in hybrid thick/thin-film circuits.

FAQ

What is the maximum drain-source voltage rating for BF510,215?

The BF510,215 has a maximum drain-source voltage (VDS) rating of 20 V, as specified in the Absolute Maximum Ratings table. This limit applies under both DC and RF conditions and must not be exceeded to prevent junction breakdown. Operation near this limit requires careful attention to peak RF voltage swings and thermal derating above Tamb = 40 °C.

Does BF510,215 require external gate biasing?

No - the BF510,215 is a depletion-mode N-channel JFET and conducts with zero gate-source voltage (VGS = 0). It is typically operated with the gate grounded or held at DC ground via a high-impedance path, relying on its intrinsic −V(P)GS ≈ 0.8 V (typ) to establish the quiescent IDSS > 0.7 mA. External negative bias is only needed for precise current control or Class-AB operation.

What is the typical noise figure of BF510,215 at 100 MHz?

The BF510,215 exhibits a typical noise figure (F) of 1.5 dB at 100 MHz when operated at VDS = 10 V, VGS = 0, with optimum source admittance (GS = 1 mS, −BS = 3 mS). This value is confirmed in both the Quick Reference Data and Dynamic Characteristics sections of the December 1997 datasheet and is central to its use in sensitive VHF receiver front-ends.

Is BF510,215 compatible with reflow soldering processes?

Yes - the BF510,215 uses the SOT23 (TO-236AB) plastic surface-mount package, which is qualified for standard lead-free reflow profiles per JEDEC J-STD-020. Its maximum junction temperature rating of 150 °C and thermal resistance of 430 K/W allow robust processing on FR-4 and ceramic substrates when mounted per the recommended 8 mm × 10 mm × 0.7 mm ceramic layout.

How does BF510,215 differ from BF512,215 in RF performance?

The BF510,215 differs from BF512,215 primarily in IDSS (>0.7 mA vs >6 mA), yfs (>2.5 mS vs >6 mS), and intended application: BF510,215 targets low-current FM portable RF amplifiers, whereas BF512,215 is optimized for mains-powered radios needing higher gain and drive. Both share identical Crs (0.3 pF) and F (1.5 dB), but BF512,215 achieves higher yfs at ID = 5 mA rather than VGS = 0.