NXP Semiconductors BF513,215

Overview

BF513,215 from NXP Semiconductors is an asymmetrical N-channel planar epitaxial junction field-effect transistor (JFET) in SOT23 package, designed for RF mixer stages in portable and mains-powered radios. It delivers IDSS = 10 mA (VDS = 10 V, VGS = 0), yfs ≥ 7 mS at 1 kHz, Crs = 0.3 pF (VDS = 10 V, ID = 5 mA), F = 1.5 dB at 100 MHz, and Ptot = 250 mW up to Tamb = 40 °C.

For engineers reviewing the BF513,215 datasheet, BF513,215 pinout, BF513,215 application, or BF513,215 equivalent, this page provides verified electrical parameters, SOT23 terminal mapping, mixer-stage noise and gain behavior, and validated alternatives for RF front-end design in consumer broadcast receivers.

Technical Context

The BF513,215 operates as a common-source RF JFET with gate-controlled depletion-mode conduction. Its low feedback capacitance (Crs = 0.3 pF) and optimized transconductance (yfs ≥ 7 mS at DC/low frequency, 5.0 mS at 100 MHz) support stable high-frequency amplification and mixing without neutralization.

It is biased at ID = 5 mA with VDS = 10 V for dynamic characterization, achieving 1.5 dB noise figure at 100 MHz under GS = 1 mS and –BS = 3 mS source admittance conditions - confirming suitability for low-noise mixer input stages in FM radio architectures.

Key Specifications

Pinout & Package

BF513,215 is housed in a plastic surface-mounted SOT23 (TO-236AB) package with 3 leads. The device uses standard pinning: Pin 1 = Gate, Pin 2 = Drain, Pin 3 = Source.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BF512,215 and BF998,215, the BF513,215 occupies a mid-tier position: it delivers higher drive (10 mA IDSS) than BF512,215 without the bias complexity and thermal demand of BF998,215 - making it optimal for cost-sensitive, volume-manufactured FM mixer designs.

Availability

BF513,215 is available at Aetrix Electronics and suitable for FM radio mixer stages, portable broadcast receiver IF amplifiers, mains-powered tuner front-ends, and hybrid thick-film RF modules requiring stable component supply and long-lifecycle support.

Supply support for BF513,215 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 BF513,215 belongs to NXP's legacy RF JFET family targeting consumer broadcast equipment; it was engineered specifically for low-noise, low-capacitance mixer and amplifier functions in FM radio hybrid circuits.

FAQ

What is the maximum drain-source voltage rating for BF513,215?

The BF513,215 has a maximum drain-source voltage (VDS) rating of 20 V, as specified in the Absolute Maximum Ratings table. This limit applies under all operating conditions and must not be exceeded to avoid permanent device damage. The BF513,215 is intended for low-voltage RF applications such as FM radio front-ends where supply rails remain well within this threshold.

How is the BF513,215 biased in typical mixer applications?

In standard mixer configurations, the BF513,215 is biased at ID = 5 mA with VDS = 10 V, as defined in its dynamic characterization conditions. This operating point achieves optimal noise figure (1.5 dB at 100 MHz) and transconductance (5.0 mS). A simple source resistor or fixed-gate-bias network establishes this condition, leveraging its IDSS = 10 mA and V(P)GS ≈ 3 V.

Does BF513,215 have automotive qualification?

No, the BF513,215 is not automotive-qualified. Per NXP's datasheet disclaimers, it is designated for consumer broadcast applications only and has not been tested or qualified to AEC-Q101 or other automotive reliability standards. Use in automotive systems is unsupported and carries no warranty from NXP Semiconductors or Aetrix Electronics.

What is the thermal resistance of BF513,215 and how does it affect layout?

The BF513,215 has a junction-to-ambient thermal resistance (Rth j-a) of 430 K/W when mounted on an 8 mm × 10 mm × 0.7 mm ceramic substrate. This value informs PCB thermal design: for continuous 250 mW dissipation, ambient temperature must stay ≤40 °C. Layouts should replicate the specified substrate dimensions and avoid excessive copper pour that alters thermal paths.

Can BF513,215 replace BF511,215 in existing designs?

No direct replacement is recommended. While both are in the BF510–513 family and share SOT23 packaging, BF511,215 has IDSS = 2.5 mA and yfs = 4 mS - significantly lower drive and gain than BF513,215 (IDSS = 10 mA, yfs ≥ 7 mS). Substituting BF513,215 would require full re-biasing and noise/gain verification; it is not a drop-in upgrade.