My Inquiry
My Account
NXP Semiconductors BF512,235
- Part No.:
- BF512,235
- Manufacturer:
- NXP Semiconductors
- Category:
- Single FETs, MOSFETs
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
BF512,235.pdf
- Description:
- RF MOSFET JFET 10V SOT23
- Quantity:
- Payment:
- Shipping:
Inventory:9,240
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
BF512,235 from NXP Semiconductors is an asymmetrical N-channel planar epitaxial junction field-effect transistor (JFET) in SOT23 package, designed for RF amplifier stages in mains-powered AM/FM radios. It delivers IDSS = 6 mA (typ), yfs ≥ 6 mS at 1 kHz, Crs = 0.3 pF (typ), F = 1.5 dB (typ) at 100 MHz, and operates up to 20 V VDS with 250 mW Ptot at Tamb ≤ 40 °C.
For engineers reviewing the BF512,235 datasheet, BF512,235 pinout, BF512,235 application, or BF512,235 equivalent, this page provides verified electrical parameters, SOT23 terminal mapping, noise performance at 100 MHz, gate cut-off voltage (−V(P)GS = 2.2 V typ), and validated alternatives for RF front-end design in consumer radio equipment.
Technical Context
The BF512,235 operates in common-source configuration with fixed-bias gate control and zero-gate-voltage drain current (IDSS) as primary operating point. Its low feedback capacitance (Crs = 0.3 pF typ) and optimized transconductance (yfs ≥ 6 mS at 1 kHz, ≥ 5.0 mS at 100 MHz) support stable gain in VHF-band amplifiers.
Thermal design relies on ceramic substrate mounting (8 mm × 10 mm × 0.7 mm), yielding Rth j-a = 430 K/W. Static operation requires VGS ≤ −2.2 V for pinch-off, with IGSS < 10 nA at VGS = −0.2 V and VDS = 0, ensuring minimal gate leakage in high-impedance bias networks.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VDS max | 20 V - maximum drain-source voltage before breakdown; sets safe DC supply headroom for RF amplifier rails. |
| IDSS | 6 mA (typ) - zero-bias drain saturation current; defines quiescent operating point without external gate bias. |
| yfs (1 kHz) | ≥6 mS - low-frequency transconductance; determines small-signal voltage gain in tuned amplifier stages. |
| Crs | 0.3 pF (typ) - feedback capacitance; minimizes Miller effect and ensures unconditional stability up to VHF. |
| F (100 MHz) | 1.5 dB (typ) - noise figure at optimum source admittance; enables high-SNR reception in mains radio IF/RF stages. |
| −V(P)GS | 2.2 V (typ) - gate-source pinch-off voltage; defines gate bias range for linear Class-A operation. |
| Ptot (Tamb ≤ 40 °C) | 250 mW - total power dissipation limit; requires thermal derating above 40 °C per Fig.4 curve. |
Pinout & Package
Package: SOT23 (TO-236AB), plastic surface-mounted, 3-lead miniature envelope per IEC 60134; dimensions: D = 2.8 mm, E = 1.4 mm, Lp = 1.2 mm, bp = 0.48 mm, c = 0.38 mm.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Gate | High-impedance control terminal; accepts DC bias or AC-coupled signal; requires <10 nA leakage path. |
| 2 | Drain | Output current node; connects to RF choke or tuned collector load; rated for 20 V and 30 mA DC. |
| 3 | Source | Reference node for gate bias; typically grounded via RF bypass capacitor or degeneration resistor. |
Key Features
| Feature | Design Value |
|---|---|
| Low feedback capacitance | Crs = 0.3 pF typ - reduces internal signal coupling, enabling stable >100 MHz gain without neutralization. |
| Low noise figure | F = 1.5 dB typ at 100 MHz - supports high-fidelity audio recovery in mains-powered broadcast receivers. |
| Asymmetrical JFET structure | Optimized for RF amplifier linearity - improves intermodulation distortion (IMD) performance in multi-channel radio front-ends. |
| Zero-gate-voltage operation | IDSS = 6 mA typ - eliminates need for negative gate supply; simplifies bias network in cost-sensitive consumer radios. |
Applications
| AM/FM Mains Radio RF Amplifier | FM Broadcast Tuner Front-End |
|---|---|
Use Scenario: First-stage RF amplifier in domestic tabletop AM/FM radio with ferrite rod antenna and 50–108 MHz tuning range. IC Role / Device Role / Timing Role: N-channel JFET configured as common-source voltage amplifier with fixed self-bias. Use Value: Delivers 1.5 dB noise figure and 6 mS transconductance to maximize weak-signal sensitivity without external gate bias circuitry. |
Use Scenario: Input stage of integrated FM tuner module receiving signals from rooftop or dipole antenna in 87.5–108 MHz band. IC Role / Device Role / Timing Role: Low-noise RF amplifier preceding mixer and IF chain; operated at ID ≈ 5 mA with VDS = 10 V. Use Value: 0.3 pF feedback capacitance ensures unconditional stability across full FM band, preventing oscillation in compact PCB layouts. |
| Portable Shortwave Receiver Preamp | RF Signal Generator Output Stage |
Use Scenario: High-impedance preamplifier for shortwave (3–30 MHz) receiver input, coupled to active whip antenna. IC Role / Device Role / Timing Role: JFET-based impedance transformer and gain block; source-follower or common-source topology. Use Value: Gate cut-off voltage of −2.2 V (typ) allows precise DC biasing for optimal dynamic range in wideband HF applications. |
Use Scenario: Final buffer amplifier in benchtop RF signal generator output path, driving 50 Ω load up to 100 MHz. IC Role / Device Role / Timing Role: Linear Class-A driver stage delivering stable gain with minimal harmonic distortion. Use Value: 250 mW power rating and 430 K/W thermal resistance enable continuous operation when mounted on ceramic substrate per spec note 1. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar RF JFET amplifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| BF511,235 | IDSS = 2.5 mA (typ), yfs ≥ 4 mS (1 kHz), −V(P)GS = 1.5 V (typ); lower gain and earlier pinch-off than BF512,235. | Better suited for car radio RF stages where lower IDSS reduces current draw from 12 V supply. | Select BF511,235 when designing for automotive 12 V systems requiring reduced quiescent current and moderate gain. |
| BF513,235 | IDSS = 10 mA (typ), yfs ≥ 7 mS (1 kHz), −V(P)GS = 3 V (typ); higher gain and later pinch-off than BF512,235. | Preferred for mixer-stage applications demanding higher transconductance and improved linearity under 5 mA bias. | Choose BF513,235 for mixer or broadband amplifier designs needing enhanced yfs and wider VGS control range. |
Compared with BF511,235 and BF513,235, the BF512,235 offers a balanced trade-off between gain (6 mS), noise (1.5 dB), and bias point (6 mA IDSS, −2.2 V V(P)GS), making it optimal for mains-powered AM/FM radio RF amplifiers where stable, low-noise gain at moderate current is required.
Availability
BF512,235 is available at Aetrix Electronics and suitable for RF amplifier stages in mains-powered AM/FM radios, FM broadcast tuners, portable shortwave receivers, and RF signal generator output buffers requiring stable component supply and long-term obsolescence management.
Supply support for BF512,235 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 specializing in high-performance mixed-signal and standard products, with leadership in RF, analog, and interface technologies.
The BF512,235 belongs to NXP's legacy discrete RF JFET family (BF510–BF513), engineered specifically for low-noise, high-stability VHF amplifier and mixer applications in consumer broadcast equipment.
FAQ
What is the typical drain current (IDSS) of the BF512,235?
The BF512,235 has a typical drain-source saturation current (IDSS) of 6 mA when VDS = 10 V and VGS = 0. This value defines its zero-bias operating point and is critical for setting quiescent current in self-biased RF amplifier configurations without external gate voltage sources.
What is the noise figure of the BF512,235 at 100 MHz?
The BF512,235 achieves a typical noise figure (F) of 1.5 dB at 100 MHz under optimum source admittance conditions (GS = 1 mS, −BS = 3 mS) with VDS = 10 V and ID = 5 mA. This low noise performance makes the BF512,235 especially suitable for sensitive RF front-end stages in mains-powered broadcast receivers.
Which package does the BF512,235 use, and what are its key mechanical dimensions?
The BF512,235 uses the SOT23 (TO-236AB) plastic surface-mount package. Key dimensions include body length D = 2.8 mm, body width E = 1.4 mm, lead pitch e1 = 1.9 mm, and overall height Lp = 1.2 mm - all compliant with IEC 60134 and suitable for automated assembly on consumer radio PCBs.
How does the BF512,235 differ from the BF513,235 in terms of transfer admittance?
The BF512,235 specifies yfs ≥ 6 mS at 1 kHz (VDS = 10 V, VGS = 0), while the BF513,235 delivers yfs ≥ 7 mS under identical conditions. At 100 MHz, BF512,235 maintains yfs ≥ 5.0 mS versus BF513,235's ≥ 5.0 mS - indicating comparable high-frequency gain but higher low-frequency drive capability in BF513,235.
What is the maximum allowable power dissipation for the BF512,235 at ambient temperature?
The BF512,235 has a maximum total power dissipation (Ptot) of 250 mW when ambient temperature (Tamb) is ≤ 40 °C, assuming mounting on an 8 mm × 10 mm × 0.7 mm ceramic substrate per specification note 1. Above 40 °C, power must be linearly derated using the curve in Figure 4 of the datasheet.
BF512,235 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
- Technology:
- JFET
- Configuration:
- N-Channel
- Frequency:
- 100MHz
- Gain:
- -
- Voltage - Test:
- 10 V
- Current Rating (Amps):
- 30mA
- Noise Figure:
- 1.5dB
- Current - Test:
- 5 mA
- Power - Output:
- -
- Voltage - Rated:
- 20 V
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23 (TO-236AB)
BF512,235 FAQ
1.How can I place an order for BF512,235 through Aetrix?
Please submit a Request for Quotation (RFQ) for BF512,235 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 BF512,235 reliable?
The price and inventory of BF512,235 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BF512,235 is usually 5 days.
3.What payment methods are accepted for BF512,235?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BF512,235 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BF512,235?
BF512,235 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BF512,235 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 BF512,235?
For technical support, including BF512,235 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BF512,235 requirements.
6.How does Aetrix verify that BF512,235 is sourced from the original manufacturer or authorized distributors?
All BF512,235 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 BF512,235 meets industry standards.
7.What is the process for return or replacement of BF512,235?
All BF512,235 units undergo pre-shipment inspection (PSI). If there is an issue with BF512,235, 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 BF512,235 part is unused and in its original packaging.
Return procedure for BF512,235:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BF512,235 Tags
-
3SK294(TE85L,F)
Toshiba Semiconductor and Storage
-
SAV-551+
Mini-Circuits
-
TAV2-501+
Mini-Circuits
-
CE3514M4-C2
CEL
-
AFT05MS004NT1
NXP USA Inc.
-
SAV-541+
Mini-Circuits
-
CE3512K2-C1
CEL
-
AFM907NT1
NXP Semiconductors
-
SKY65050-372LF
Skyworks Solutions Inc.
-
CE3520K3-C1
CEL
-
AFT09MS007NT1
NXP USA Inc.
-
AFT09MS015NT1
NXP USA Inc.
Tech Hub
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.
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…
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…
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…
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 …
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…
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…
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…
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…
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…
