Nexperia USA Inc. BF824W,135

Overview

BF824W,135 from Nexperia is a PNP medium-frequency transistor in SOT323 package, rated for −30 V V_CEO, −25 mA I_C, and 250–400 MHz f_T, designed for RF amplification in FM front-end common-base configurations.

For engineers reviewing the BF824W,135 datasheet, BF824W,135 pinout, BF824W,135 application, or BF824W,135 equivalent, this device serves as a low-current, low-voltage RF gain element with verified thermal resistance (625 K/W), Crb ≤ 0.3 pF, and h_FE ≥ 25 at −1 mA.

Technical Context

The BF824W,135 operates as a PNP bipolar junction transistor optimized for medium-frequency RF amplification, using common-base topology to achieve high f_T (up to 400 MHz at −4 mA) and low feedback capacitance (C_rb ≤ 0.3 pF).

Its design targets stable small-signal gain in FM receiver front-ends, with V_BE = −900 mV at −4 mA/−10 V and ICBO ≤ −50 nA at −30 V, ensuring low leakage and predictable biasing under ambient temperatures from −65 °C to +150 °C.

Key Specifications

Pinout & Package

SOT323 plastic surface-mount package (3-lead, SC-70 compatible), dimensions: 2.2 × 1.35 × 0.95 mm (L × W × H), with gull-wing leads and exposed die pad not electrically connected.

Key Features

Applications

Availability

BF824W,135 is available at Aetrix Electronics and suitable for FM radio front-ends, portable audio tuners, and ISM band receiver preamplifiers requiring stable component supply and long-term obsolescence management.

Supply support for BF824W,135 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

Nexperia is a global leader in discrete, logic, and PowerMOS semiconductors, formed in 2017 from the former NXP Standard Products division, serving automotive, industrial, computing, and consumer markets.

The BF824W,135 belongs to Nexperia's RF bipolar transistor product line, engineered specifically for medium-frequency small-signal amplification in cost-sensitive, space-constrained FM and ISM band receivers.

FAQ

Is BF824W,135 suitable for common-emitter RF amplifier designs?

No - the BF824W,135 is characterized and optimized for common-base operation, with specified f_T, C_rb, and gain data only under common-base conditions (e.g., IC = −4 mA, V_CE = −10 V). Its low h_FE and high C_rb-limited stability make it unsuitable for common-emitter RF stages requiring high input impedance or phase inversion.

What is the maximum allowable PCB copper area for thermal relief on the SOT323 footprint?

The datasheet specifies R_{th j-a} = 625 K/W for mounting on standard FR4 with no added copper. Adding 10 mm² of 1 oz copper connected to pin 3 (collector) reduces R_{th j-a} by ~150 K/W per mm²; however, Nexperia does not publish derating curves for extended copper, so thermal validation is required for designs exceeding 200 mW.

Does BF824W,135 have a qualified AEC-Q101 rating for automotive use?

No - the BF824W,135 is not AEC-Q101 qualified. It is specified for industrial and consumer applications, with operating ambient temperature range −65 °C to +150 °C but without automotive-grade stress testing, failure rate reporting, or PPAP documentation per AEC-Q101 requirements.

Can BF824W,135 replace BF199 in existing FM front-end designs?

Not directly - while both are PNP RF transistors, BF199 uses TO-92 package (higher R_{th j-a}), has higher f_T (≥600 MHz), and different pinout (E-B-C vs. B-E-C). Layout, thermal, and matching network redesign would be required; BF824W,135 offers lower cost and smaller footprint but reduced bandwidth margin.