Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Transistors > Bipolar (BJT) > Bipolar RF Transistors

NXP Semiconductors BFS17,235

Name: BFS17,235
Brand: NXP Semiconductors
SKU: BFS17,235
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: BFS17,235

Manufacturer:: NXP Semiconductors

Category:: Bipolar RF Transistors

Package:: TO-236-3, SC-59, SOT-23-3

Datasheet:: BFS17,235.pdf

Description:: RF TRANS NPN 15V 1GHZ TO236AB

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:8,764

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

BFS17,235 from NXP Semiconductors is an NPN silicon RF transistor in SOT23 package, rated for 1 GHz transition frequency (f_T), 15 V V_CEO, 25 mA I_C, and 4.5 dB noise figure at 500 MHz - optimized for mixer and oscillator stages in TV tuners and RF communications equipment.

For engineers reviewing the BFS17,235 datasheet, BFS17,235 pinout, BFS17,235 application, or BFS17,235 equivalent, key selection criteria include its 1 GHz f_T, low 4.5 dB noise figure at 500 MHz, SOT23 thermal resistance of 260 K/W, and verified performance in 50 Ω RF signal paths with V_CE = 5 V bias.

Technical Context

The BFS17,235 operates as a high-frequency NPN amplifier with f_T up to 1.6 GHz at I_C = 25 mA and V_CE = 5 V, supporting wideband RF gain across 100–1000 MHz bands. Its low C_c (0.8–1.5 pF) and C_re (0.65 pF) minimize feedback and enable stable oscillator design.

Designed for Class-A small-signal operation, it delivers h_FE = 25–90 over I_C = 2–25 mA and maintains F = 4.5 dB minimum at I_C = 2 mA, V_CE = 5 V, R_S = 50 Ω - critical for low-noise front-end amplification in broadcast receivers.

Key Specifications

Parameter	Value and Actual Design Meaning
f_T	1.6 GHz at I_C = 25 mA - enables stable amplification up to UHF band without external neutralization
Noise Figure	4.5 dB at 500 MHz - meets low-noise requirement for TV tuner IF/RF stages
V_CEO	15 V - supports standard 12 V supply rails in consumer RF modules with margin
I_C max	25 mA DC - defines maximum linear output power in small-signal amplifier configurations
C_c	0.8–1.5 pF at V_CB = 10 V - ensures minimal Miller effect in broadband amplifier designs
R_{th j-s}	260 K/W - limits junction temperature rise under 300 mW P_tot in SOT23 PCB layout

Pinout & Package

Package: SOT23 (TO-236AB), plastic surface-mounted, 3-lead, marking code E1p. Dimensions per IEC/JEDEC outline: D = 2.8 mm, E = 1.4 mm, L_p = 1.2 mm, e = 1.9 mm.

Pin/Terminal	Circuit Role	Design Meaning
1	Base	Control electrode for current amplification; requires 50 Ω impedance match in RF input networks
2	Emiter	Common reference node in common-base configuration; grounded for RF stability in oscillator circuits
3	Collector	RF output node with soldering-point thermal path; primary heat dissipation route in SOT23 layout

Key Features

Feature	Design Value
High f_T bandwidth	1.6 GHz at full rated current - supports direct amplification in VHF/UHF receiver front-ends without cascading
Low noise figure	4.5 dB at 500 MHz - enables high SNR in weak-signal TV tuner applications
Stable SOT23 thermal path	R_{th j-s} = 260 K/W - allows continuous 300 mW operation with controlled junction temperature rise
Low feedback capacitance	C_re = 0.65 pF - reduces risk of oscillation in high-gain amplifier stages

Applications

TV Tuner Mixers	UHF Oscillators
Use Scenario: Local oscillator injection and RF-to-IF mixing in analog/digital terrestrial TV tuners. IC Role / Device Role / Timing Role: NPN active device in common-emitter mixer core and Colpitts oscillator tank circuit. Use Value: 1.6 GHz f_T and 4.5 dB noise figure ensure clean LO generation and low-conversion-loss mixing at 470–862 MHz.	Use Scenario: Compact voltage-controlled oscillator (VCO) for channel selection in cable/satellite set-top boxes. IC Role / Device Role / Timing Role: Gain element in LC-tuned feedback oscillator with varactor tuning diode. Use Value: Low C_c (0.8–1.5 pF) and C_re (0.65 pF) minimize frequency drift and improve phase noise performance.
RF Communications Receivers	FM Radio Front-Ends
Use Scenario: First-stage LNA in portable two-way radios operating at 136–174 MHz or 400–470 MHz bands. IC Role / Device Role / Timing Role: Low-noise amplifier in common-emitter configuration with emitter degeneration. Use Value: 4.5 dB noise figure at 500 MHz scales favorably to sub-500 MHz bands, preserving receiver sensitivity.	Use Scenario: RF amplifier and detector stage in mono/stereo FM radio ICs for automotive and portable audio. IC Role / Device Role / Timing Role: Small-signal amplifier driving quadrature detector or PLL-based demodulator. Use Value: h_FE = 25–90 over 2–25 mA enables stable gain control across battery voltage range (4.5–12 V).

TV Tuner Mixers

UHF Oscillators

Use Scenario: Local oscillator injection and RF-to-IF mixing in analog/digital terrestrial TV tuners.

IC Role / Device Role / Timing Role: NPN active device in common-emitter mixer core and Colpitts oscillator tank circuit.

Use Value: 1.6 GHz f_T and 4.5 dB noise figure ensure clean LO generation and low-conversion-loss mixing at 470–862 MHz.

Use Scenario: Compact voltage-controlled oscillator (VCO) for channel selection in cable/satellite set-top boxes.

IC Role / Device Role / Timing Role: Gain element in LC-tuned feedback oscillator with varactor tuning diode.

Use Value: Low C_c (0.8–1.5 pF) and C_re (0.65 pF) minimize frequency drift and improve phase noise performance.

RF Communications Receivers

FM Radio Front-Ends

Use Scenario: First-stage LNA in portable two-way radios operating at 136–174 MHz or 400–470 MHz bands.

IC Role / Device Role / Timing Role: Low-noise amplifier in common-emitter configuration with emitter degeneration.

Use Value: 4.5 dB noise figure at 500 MHz scales favorably to sub-500 MHz bands, preserving receiver sensitivity.

Use Scenario: RF amplifier and detector stage in mono/stereo FM radio ICs for automotive and portable audio.

IC Role / Device Role / Timing Role: Small-signal amplifier driving quadrature detector or PLL-based demodulator.

Use Value: h_FE = 25–90 over 2–25 mA enables stable gain control across battery voltage range (4.5–12 V).

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN RF transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BF199,112	f_T = 1.2 GHz (max), higher V_CEO = 25 V, but higher noise figure (6 dB at 500 MHz)	Better suited for higher-voltage RF amplifier stages where noise is secondary to breakdown margin	Select when >15 V supply or higher collector swing is required; verify layout for increased C_c (1.2 pF)
BFR92A,215	f_T = 5 GHz, lower noise figure (2.5 dB), but tighter bias sensitivity and higher cost	Used in high-performance GPS/LTE front-ends requiring ultra-low noise and wide bandwidth	Choose only if system-level noise budget demands <3 dB NF and f_T > 3 GHz; requires precise bias network tuning

Compared with BF199,112 and BFR92A,215, the BFS17,235 offers optimal balance of 1.6 GHz bandwidth, 4.5 dB noise, and SOT23 manufacturability for cost-sensitive TV tuner and consumer RF designs - neither highest f_T nor lowest NF, but best overall fit for mainstream broadcast applications.

Availability

BFS17,235 is available at Aetrix Electronics and suitable for TV tuner mixers, UHF oscillators, and RF communications receivers requiring stable component supply and long-term obsolescence management.

Supply support for BFS17,235 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 product solutions, with leadership in RF, analog, and interface technologies.

The BFS17,235 belongs to NXP's legacy RF transistor family designed specifically for consumer broadcast equipment - emphasizing manufacturability in SOT23, consistent noise performance, and compatibility with automated TV tuner assembly lines.

FAQ

What is the maximum operating frequency of the BFS17,235?

The BFS17,235 has a transition frequency (f_T) of 1.6 GHz at I_C = 25 mA and V_CE = 5 V, confirmed in the NXP product specification. This defines its usable upper limit for small-signal amplification; practical RF gain remains effective up to ~800 MHz in tuned amplifier configurations. The BFS17,235 is not rated for switching or power amplification above this range.

Can the BFS17,235 be used in a common-base configuration?

Yes, the BFS17,235 supports common-base operation, as confirmed by its specified V_CB rating (25 V) and low C_re (0.65 pF), which minimizes feedback instability. In TV tuner oscillator designs, the emitter is typically grounded - making the BFS17,235 function in common-base mode. Its h_FE and f_T characteristics remain valid under this bias arrangement.

What is the thermal resistance of the BFS17,235 and how does it affect PCB layout?

The BFS17,235 has a junction-to-soldering-point thermal resistance (R_{th j-s}) of 260 K/W, measured at the collector pin solder joint. This means a 300 mW power dissipation causes ~78 °C junction-to-solder-point rise. To maintain T_j ≤ 150 °C, the PCB must keep the collector pad temperature ≤ 72 °C - achieved via ≥ 10 mm² copper pour and minimal thermal via isolation.

Is the BFS17,235 suitable for automotive applications?

No, the BFS17,235 is not automotive-qualified. Per NXP's 1995 product specification and disclaimers, it is designated for consumer broadcast and general RF applications only. It lacks AEC-Q101 qualification, extended temperature validation beyond –65 to +150 °C, and automotive-grade reliability testing. For automotive use, consider NXP's later-generation RF transistors explicitly marked "automotive qualified".

How does the noise figure of the BFS17,235 vary with collector current?

The BFS17,235 achieves minimum noise figure of 4.5 dB at I_C = 2 mA, V_CE = 5 V, and 500 MHz, per Figure 5 in the datasheet. Noise rises to ~6 dB at I_C = 25 mA due to increased shot noise. For low-noise amplifier design, biasing the BFS17,235 near 2 mA optimizes SNR - a key consideration in TV tuner front-end stages where signal integrity is critical.

BFS17,235 Specifications

Product attributes: Attribute value

Manufacturer:: NXP Semiconductors

Series:: -

Package/Case:: TO-236-3, SC-59, SOT-23-3

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Transistor Type:: NPN

Voltage - Collector Emitter Breakdown (Max):: 15V

Frequency - Transition:: 1GHz

Noise Figure (dB Typ @ f):: 4.5dB @ 500MHz

Gain:: -

Power - Max:: 300mW

DC Current Gain (hFE) (Min) @ Ic, Vce:: 25 @ 2mA, 1V

Current - Collector (Ic) (Max):: 25mA

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: SOT-23 (TO-236AB)

BFS17,235 FAQ

1.How can I place an order for BFS17,235 through Aetrix?

Please submit a Request for Quotation (RFQ) for BFS17,235 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for BFS17,235 reliable?

The price and inventory of BFS17,235 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BFS17,235 is usually 5 days.

3.What payment methods are accepted for BFS17,235?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BFS17,235 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BFS17,235?

BFS17,235 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BFS17,235 order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for BFS17,235?

For technical support, including BFS17,235 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BFS17,235 requirements.

6.How does Aetrix verify that BFS17,235 is sourced from the original manufacturer or authorized distributors?

All BFS17,235 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that BFS17,235 meets industry standards.

7.What is the process for return or replacement of BFS17,235?

All BFS17,235 units undergo pre-shipment inspection (PSI). If there is an issue with BFS17,235, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The BFS17,235 part is unused and in its original packaging.

Return procedure for BFS17,235:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-03 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-01 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…