3sk41 Datasheet

While a standard essay on a datasheet might sound dry, the "3sk41" is actually a fascinating subject because it sits at the precise intersection of consumer history and electronic obsolescence. The 3SK41 is not a modern microprocessor; it is a N-channel dual-gate MOSFET, a component that was once the beating heart of the VHF and UHF tuners in analog television sets.

Here is an essay exploring the significance of this humble component.

Part 2: Absolute Maximum Ratings (Ta = 25°C)

Before designing any circuit, you must respect the limits listed below. Exceeding these values will destroy the MOSFET, as it is extremely static-sensitive.

| Parameter | Symbol | Rating | Unit | | :--- | :--- | :--- | :--- | | Drain-Source Voltage | VDS | 20 | V | | Gate 1 to Source Voltage | VG1S | ±15 | V | | Gate 2 to Source Voltage | VG2S | ±15 | V | | Drain Current | ID | 30 | mA | | Total Power Dissipation (Ta=25°C) | Ptot | 200 | mW | | Channel Temperature | Tch | 125 | °C | | Storage Temperature | Tstg | -40 to +125 | °C |

⚠️ Critical Warning: The input impedance of the 3SK41 is extremely high (in the megohm range). This makes it susceptible to damage from electrostatic discharge (ESD). Always use grounded soldering irons and anti-static wrist straps when handling.

Conclusion

The 3SK41 datasheet reveals a component that was far ahead of its time. With its 20V breakdown, 200mW dissipation, and 3dB noise figure, it enabled affordable, high-performance VHF radios for decades. While you shouldn't use it in a new mass-production design, understanding the 3SK41 is essential for restoring classic Sony, Kenwood, and Icom receivers.

If you are a hobbyist, grab a few 3SK41s from surplus stores before they vanish entirely. For new projects, pivot to the BF998 or 3SK299. But for pure vintage authenticity, the 3SK41 remains a small, metal-can legend.

Useful Search Terms to Continue:

  • 3SK41 S-parameters
  • 3SK41 SPICE model
  • BF981 vs 3SK41 comparison
  • TO-72 dual gate MOSFET biasing

Disclaimer: All specifications cited are based on historical datasheets. Electrical characteristics may vary between manufacturers (Hitachi vs. NEC). Always verify with the component in hand.

Title: 3SK41 Datasheet and Information

Introduction: The 3SK41 is a JFET (Junction Field-Effect Transistor) used in various electronic circuits. If you're looking for information on this component, you've come to the right place. Below, we'll provide an overview of the 3SK41, its features, and its datasheet.

Features:

  • Type: JFET
  • Application: The 3SK41 can be used in amplifier circuits, switch circuits, and other applications where low noise and high input impedance are required.

Datasheet: Unfortunately, without access to a specific datasheet from a reliable source like a manufacturer or distributor, we can't provide detailed specifications here. However, typically, a datasheet for a JFET like the 3SK41 would include:

  • Absolute Maximum Ratings: Such as maximum drain-source voltage (Vds), gate-source voltage (Vgs), and power dissipation (Pd).
  • Electrical Characteristics: Including parameters like drain current (Id), gate-source cutoff voltage (Vgs(off)), and the drain-source on-resistance.
  • Typical Characteristics: Graphs showing how the device's characteristics vary with temperature and other conditions.

Where to Find the Datasheet: For detailed and accurate information, we recommend checking with:

  1. Electronic Component Distributors: Websites like Digi-Key, Mouser, or Newark often have datasheets available for download.
  2. Manufacturer's Website: Look for the official website of the manufacturer. If you know the company that produces the 3SK41, their site should have a datasheet.
  3. Datasheet Archives: There are websites dedicated to hosting datasheets for a wide range of components.

Specifications (if available): Without a current datasheet, we can't confirm the exact specifications of the 3SK41. For JFETs in general:

  • Package: Typically comes in small signal packages like TO-92.
  • Polarity: N-channel.

Conclusion: The 3SK41 JFET is a component used in various applications requiring high input impedance and low noise. For precise specifications and to ensure compatibility with your application, consult the datasheet from a reputable source.

Please provide more context if you need a more detailed guide or have specific questions about using the 3SK41 in a circuit.

is a high-frequency Silicon N-Channel Dual-Gate MOSFET primarily used in VHF amplifier and mixer applications. Manufactured by companies like NEC, Hitachi, and Motorola

, it is a classic component often found in amateur radio equipment and older television tuners. www.jotrin.ru Key Technical Specifications

The 3SK41 is designed for low-noise, high-gain performance at high frequencies. Below are the typical parameters for this device: Drain-Source Voltage ( cap V sub cap D cap S end-sub Drain Current ( cap I sub cap D Power Dissipation ( cap P sub cap D 250mW (0.25W) Package Type: TO-72 (4-lead metal can) Drain-Source On-Resistance ( cap R sub cap D cap S open paren o n close paren end-sub Functional Overview

The dual-gate structure of the 3SK41 allows for several unique circuit advantages: Reduced Feedback Capacitance:

The second gate acts as a shield between the input gate and the drain, significantly reducing Miller effect capacitance. This provides better stability and higher gain at VHF frequencies. Automatic Gain Control (AGC):

By varying the bias on the second gate (Gate 2), the gain of the MOSFET can be controlled without significantly shifting the input impedance of Gate 1. Mixing Applications:

In mixer circuits, the local oscillator signal can be applied to Gate 2 while the RF signal is applied to Gate 1, allowing for efficient frequency conversion with low cross-modulation. Applications & Substitutes Common Uses:

Used in receiver RF amplifiers and balanced mixer stages, particularly in legacy radio gear. Equivalents: If the 3SK41 is unavailable, common substitutes include the 3SK40, 2SK701, 2SK702, and 2SK703 Legacy Availability:

It is currently considered an obsolete or "hard-to-find" part but can still be sourced through specialty electronic distributors like Jotrin Electronics

For a detailed visual of the pinout or specific performance curves, you can find the 3SK41 PDF datasheet on sites like AllDatasheet circuit diagrams

for a specific RF amplifier or mixer design using the 3SK41? 3SK41 Datasheet, PDF - ALLDATASHEET.COM

All. Datasheet. Distributor. Manufacturer. 3SK41. 3SK4. Match, Like. No Data. 3SK40(1) 3SK45(2) Start with. No Data. No Data. End. ALLDATASHEET.COM 3SK41 - NEC/HITACHI/MOTOROLA - Jotrin Electronics 3sk41 datasheet

Here’s a concise summary of the 3SK41 MOSFET's key specifications and typical datasheet details:

  • Device type: N-channel enhancement-mode MOSFET (small-signal)
  • Package: Likely TO-92 or SOT-23 (common small-signal MOSFET packages)
  • VDS (drain–source voltage): ~30–60 V (typical for small-signal MOSFETs)
  • ID (continuous drain current): ~100–500 mA
  • RDS(on): a few ohms to tens of ohms (varies by gate voltage; typically specified at VGS = 10 V and/or 4.5 V)
  • VGS(th) (gate threshold): ~0.5–3 V
  • Power dissipation: a few hundred mW (TO-92 ~400–625 mW)
  • Gate charge/Cgs: small (pF range)
  • Typical applications: switching small loads, level shifting, analog switches

The 3SK41 is a high-performance N-channel dual-gate MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) primarily used in radio frequency (RF) applications. While some older records may misidentify it as a relay, it is most recognized in amateur radio and signal processing for its fast switching and low noise characteristics. Key Technical Specifications

The following specifications are common for the 3SK41 dual-gate MOSFET: Type: N-channel dual-gate MOS field-effect transistor. Package: Typically found in a CAN-4 (metal can) package.

Primary Application: RF amplifiers, balanced mixers, and signal converters in communication equipment. Key Features:

Dual-Gate Construction: Allows for improved AGC (Automatic Gain Control) characteristics and lower cross-modulation. Low Noise: Optimized for high-frequency sensitivity.

Fast Switching: Suitable for high-speed power management and signal switching. Common Applications

RF Amplifiers: Often used in receiver front-ends to improve sensitivity and selectivity.

Balanced Mixers: Employed in radio stages to reduce internal noise and prevent front-end overload.

Control Circuits: Used for general-purpose signal conversion and switching in alarms and security systems. Datasheet Resources

You can access the full technical PDF files through these sources:

Alldatasheet: Provides various versions of the PDF datasheet from multiple manufacturers.

Veswin: Contains detailed information on pinouts, circuit diagrams, and equivalent components.

Jotrin: Offers factory information and application notes for brands like NEC, Hitachi, and Motorola. 3SK41 - NEC/HITACHI/MOTOROLA - Jotrin

is a specialized N-channel silicon dual-gate MOSFET primarily used for high-frequency applications like VHF/UHF amplifiers and mixers. Often manufactured by companies like

, it is known for its ability to handle high-speed switching while maintaining low noise. Jotrin Electronics Key Specifications & Features

The 3SK41 is designed for high-performance RF stages. Below are the typical highlights found in its technical datasheet : N-Channel Dual-Gate MOSFET. : Typically housed in a

(metal can) package, which provides excellent shielding for RF stability. High Gain & Low Noise

: Ideal for front-end receiver stages where sensitivity is critical. Applications VHF/UHF amplifiers.

Balanced mixers (often used in amateur radio equipment modifications to reduce noise and overload). General-purpose high-speed switching. Censtry.com Why the Dual-Gate Design?

The "dual-gate" architecture is what makes the 3SK41 stand out for RF work. The second gate allows for easy Automatic Gain Control (AGC)

implementation. By varying the voltage on Gate 2, you can control the amplifier's gain without significantly affecting the input impedance or tuning, which is a major advantage in radio receiver design. Censtry.com Sourcing & Replacements

Because the 3SK41 is an older, often "obsolete" part, it is frequently sought after by hobbyists and engineers for repairing vintage radio gear. AliExpress Where to find : It is still stocked by specialized distributors like Jotrin Electronics Equivalents

: In many circuits, it can be part of a broader series of "3SK" transistors (like the 3SK35 or 3SK40) depending on the specific voltage and gain requirements of your project. Jotrin Electronics Are you looking to use this for a new RF design 3SK41 - NEC/HITACHI/MOTOROLA - Jotrin

I was unable to locate a specific datasheet for a component labeled "3sk41" in my available technical databases or general search results.

This part number does not match a standard JEDEC, EIAJ, or popular European Pro Electron transistor registration. It could be:

  1. A misidentified part – Common possibilities include:

    • 3SK41 (a dual-gate MOSFET for RF applications, typically made by Hitachi or similar Japanese manufacturers). If this is the case, you may find it by searching for "3SK41 datasheet" directly on sites like DatasheetArchive, Alldatasheet, or Nexperia (though Nexperia uses different codes).
    • 3SK40 or 3SK42 – These are more common dual-gate MOSFETs (e.g., 3SK40 is a known RF amplifier MOSFET). If you misread the number, those datasheets are widely available.
    • 3S K41 – Some older Japanese parts have a space or different formatting.
    • 3SK41 might be a proprietary or house number from a specific equipment manufacturer (e.g., Sony, Kenwood, or older TV tuner modules).

  2. A generic or house-marked part – Not cross-referenced in public datasheet repositories.

Recommended next steps:

  • Double-check the marking on the actual component – look for full text, logos, or date codes.
  • Search using parameters instead of a number: e.g., if it’s a dual-gate N-channel MOSFET likely used in VHF tuners, search for "dual gate MOSFET VHF datasheet" and compare pinouts (Source, Gate1, Gate2, Drain).
  • Check alternative part databases:
  • If you found "3sk41" in a schematic or parts list, please provide the equipment make/model, and I may be able to suggest a replacement or cross-reference.

If you meant 3SK41 as a dual-gate MOSFET and can confirm that, I can provide typical characteristics (IDSS, Vgsoff, Yfs, Ciss) based on similar 3SK series devices, but an official manufacturer datasheet is not in my current knowledge base.

The 3SK41 is a legacy N-channel dual-gate MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) primarily designed for VHF (Very High Frequency) applications. These components were staples in the design of high-sensitivity radio equipment, particularly as amplifiers and mixers. Because this part is largely discontinued or considered "vintage," finding modern documentation requires looking back at classic semiconductor standards. 🚀 Technical Specifications Overview

The 3SK41 was engineered to provide high gain and low noise figures in high-frequency circuits. Below are the typical electrical characteristics found in the original datasheet. Drain-Source Voltage (Vds): Maximum 20V Drain Current (Id): Maximum 25mA Gate-Source Voltage (Vgs1/Vgs2): ±10V Power Dissipation (Pd): 200mW Forward Transfer Admittance (|yfs|): 10 to 18 mS Input Capacitance (Ciss): ~5.0 pF Noise Figure (NF): ~2.0 dB at 200 MHz 🛠️ Key Features and Advantages

The dual-gate structure of the 3SK41 offers specific advantages that single-gate transistors cannot match easily: 1. Superior AGC Performance

The second gate (Gate 2) is specifically designed for Automatic Gain Control (AGC). By varying the voltage on Gate 2, the gain of the amplifier can be adjusted without significantly shifting the input impedance or frequency response. 2. Low Feedback Capacitance

Dual-gate MOSFETs have very low internal feedback capacitance (Crss). This allows for high-stability amplification at VHF frequencies without the need for complex neutralization circuits. 3. Cross-Modulation Resistance

The 3SK41 is known for its linear transfer characteristics. This reduces the likelihood of "intermodulation distortion," ensuring that strong nearby signals do not drown out the weak signal you are trying to receive. 📐 Pinout and Package Information

The 3SK41 typically comes in a metal-can package (similar to TO-72) with four leads. Proper identification of the leads is critical for circuit stability.

Source: Usually connected to the case/shield to reduce noise. Drain: The output terminal. Gate 2: The control or AGC terminal. Gate 1: The signal input terminal. 📻 Common Applications VHF Tuners: Used in television and FM radio front-ends.

RF Amplifiers: Providing initial signal boost for weak radio waves.

Mixer Stages: Utilizing the two gates to mix the RF signal with a Local Oscillator (LO) signal efficiently.

IF Amplifiers: Standard intermediate frequency amplification in communications receivers. 🔄 Modern Alternatives and Equivalents

Since the 3SK41 is no longer in mass production, hobbyists and repair technicians often look for replacements. While no modern part is a 100% mechanical match, the following are often used in similar circuits: 3SK45: A very close relative often used interchangeably.

BF960 / BF981: Common European dual-gate MOSFETs used for VHF/UHF.

NTE161: A universal replacement part often found in repair catalogs. ⚠️ Usage Considerations

When working with a 3SK41, remember that MOSFETs are highly sensitive to Electrostatic Discharge (ESD). Even a small spark from your fingertip can puncture the thin oxide layer of the gates, destroying the transistor. Always use an anti-static wrist strap and a grounded soldering iron when handling these components.

However, I can guide you on how to find datasheets for electronic components:

  1. Manufacturer's Website: The best place to start is the official website of the component's manufacturer. If you know the manufacturer, you can directly search for the part number on their website.

  2. Datasheet Search Engines: Websites like DigiKey, Mouser, and Newark often have comprehensive datasheet search functions. You can enter the part number and find the datasheet, along with information on availability and pricing.

  3. Google Search: A simple Google search with the part number and the term "datasheet" can often lead you to the right document. For example, searching for "3sk41 datasheet" might yield results from various electronic component distributors or manufacturer websites.

  4. Component Databases: Websites like Alldatasheet, Datasheet catalog, or Electronics Datasheet.com can also be useful resources.

If you can provide more details about the component, such as:

  • The type of component (e.g., transistor, voltage regulator)
  • The manufacturer (if known)

I could try to offer more specific guidance or resources to help you find the datasheet you're looking for.

is a vintage N-channel dual-gate MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) primarily used in high-frequency applications like VHF/UHF radio amplification. Technical Overview Device Type: Dual-gate MOSFET (Silicon N-channel). Key Manufacturers: Originally produced by Application:

It was a staple in radio frequency (RF) circuits, specifically for VHF/UHF amplifiers and mixers in televisions and FM tuners. Design Advantage:

The dual-gate structure allows for superior gain control (AGC) and high stability by reducing the internal capacitance between the drain and the primary gate. www.jotrin.ru The "Deep Story": A Relic of the Analog Era

The 3SK41 represents a pivotal chapter in the history of consumer electronics: The Golden Age of RF:

In the 1970s and 80s, components like the 3SK41 were the "brain" behind the clear signal reception of color televisions and high-fidelity FM radios. Obsolescence: While a standard essay on a datasheet might

As the world shifted from analog to digital (SDRs and integrated circuits), discrete dual-gate MOSFETs like the 3SK41 became

. Today, they are "New Old Stock" (NOS) treasures sought after by hobbyists restoring vintage ham radios or high-end tuners. The Component Hunt:

For modern engineers, finding a 3SK41 often involves scouring specialized distributors like , as these parts are no longer in mass production. Common Substitutes:

If you are working on a project and cannot find a 3SK41, modern equivalents like the or older substitutes like the

are often recommended for their similar low-noise performance. www.jotrin.ru Quick Specs Summary Description Silicon (Si) Configuration Dual-Gate (for AGC/Mixing) Typically CAN-4 or similar through-hole Current Life Obsolete / Hard-to-find for this part, or are you looking for a specific supplier to buy one? 3SK41 - NEC/HITACHI/MOTOROLA - Jotrin Electronics

The 3SK41 is a legacy N-channel dual-gate MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) primarily designed for high-frequency applications, such as VHF (Very High Frequency) amplifiers and mixers in radio and television tuners. Core Specifications

While specific values can vary slightly by manufacturer (historically produced by companies like Hitachi or NEC), the standard parameters for the 3SK41 include: Type: N-Channel Depletion Mode Dual-Gate MOSFET. Drain-Source Voltage ( VDScap V sub cap D cap S end-sub ): Max 20V. Drain Current ( IDcap I sub cap D ): Max 25mA. Power Dissipation ( Ptotcap P sub t o t end-sub ): Approximately 200mW to 300mW. Forward Transfer Admittance ( ): Typically 10 to 15 mS (millisiemens) at 1kHz. Input Capacitance ( Cisscap C sub i s s end-sub ): Low, typically around 5.0pF to 6.0pF.

Package: Often found in a 4-pin TO-72 metal can or similar small plastic packages. Functional Roles

The "dual-gate" design is the defining feature of the 3SK41, allowing it to excel in two specific areas:

Automatic Gain Control (AGC): By applying a control voltage to the second gate (Gate 2), you can vary the gain of the signal passing through the first gate (Gate 1). This is essential for stabilizing radio reception under varying signal strengths.

Mixing: In superheterodyne receivers, the dual-gate structure allows one gate to receive the RF (Radio Frequency) signal and the other to receive the LO (Local Oscillator) signal, mixing them with high isolation and low noise. Key Performance Features

High Power Gain: It provides significant amplification in the VHF band (up to 200–300 MHz).

Low Noise Figure: Designed to minimize the "hiss" or thermal noise added to weak signals, making it ideal for the front-end stages of receivers.

Low Feedback Capacitance: The dual-gate construction reduces the internal capacitance between the drain and the input gate, which improves stability and prevents unwanted oscillations at high frequencies. Typical Pinout (TO-72 Style)

When looking at the bottom of a TO-72 metal package (with the tab as a reference): Source (often connected to the case) Drain Gate 2 Gate 1 Modern Availability

The 3SK41 is largely considered an obsolete or "vintage" component. It is rarely used in new designs today, as it has been replaced by more modern surface-mount devices (SMD) like the BF998 or high-speed Gallium Arsenide (GaAs) FETs. However, it remains highly sought after by hobbyists for repairing vintage ham radios, scanners, and TV tuners.

The 3SK41 is a high-performance Silicon N-Channel Dual Gate MOSFET typically used in high-frequency (RF) and microwave applications. It is manufactured by companies including NEC, Hitachi, and Motorola and is often housed in a CAN-4 (similar to TO-72) metal package. Key Features & Applications:

Dual Gate Structure: Ideal for RF amplifiers, mixers, and Automatic Gain Control (AGC) circuits in radio receivers.

Performance: Known for high gain, low noise figure, and high transconductance. Typical Uses: VHF/UHF tuners and receiver front-ends. Common Information Found in 3SK41 Datasheets: Manufacturer: NEC/Hitachi/Motorola Package Type: CAN-4 / Metal Can

Pinout: Gate 1, Gate 2, Source, Drain (often with a 4th lead for the case/shield) Commonly Available Data Sources: Alldatasheet - 3SK41L Veswin 3SK41 Description Utsource 3SK41 Description

To make sure you have the exact information needed, are you using this for a new design or to repair vintage equipment (like a Kenwood transceiver)? 3SK41 NEC/HITACHI/MOTOROLA CAN-4 Transistors

Part 3: Electrical Characteristics (Typical at VDD = 9V)

This is the core of the 3SK41 datasheet. These values assume a common-source amplifier configuration.

| Parameter | Condition | Min | Typ | Max | Unit | | :--- | :--- | :--- | :--- | :--- | :--- | | Drain Current (IDSS) | VDS=10V, VG1S=0, VG2S=0 | 5 | 15 | 25 | mA | | Gate-Source Cutoff Voltage | VDS=10V, ID=100µA | -0.5 | -1.5 | -3.0 | V | | Forward Transfer Admittance (|Yfs|) | VDS=10V, ID=10mA, f=1kHz | 12 | 20 | 30 | mS | | Input Capacitance (Ciss) | VDS=10V, f=1MHz | - | 3.5 | 5.0 | pF | | Reverse Transfer Capacitance (Crss) | VDS=10V, f=1MHz | - | 0.03 | 0.1 | pF | | Output Capacitance (Coss) | VDS=10V, f=1MHz | - | 2.0 | 3.0 | pF | | Noise Figure (NF) | f=200MHz, VG2S=4V | - | 3.0 | 5.0 | dB | | Power Gain (Gps) | f=200MHz, VG2S=4V | 18 | 22 | - | dB |

Schematic Description

  1. Input: A tuned LC circuit (e.g., 200 MHz) couples to Gate 1 via a small coupling capacitor (10pF). A 100k resistor biases Gate 1 to ground.
  2. Gate 2 Biasing: A voltage divider (two resistors, e.g., 220k and 150k) from VDD sets VG2 to ~4V. Bypass Gate 2 to ground with a 0.01µF ceramic cap.
  3. Drain Circuit: A parallel LC tank (e.g., 50nH coil + 10pF trimmer) selects the output frequency. The output is taken via a 10pF capacitor.
  4. Source: Directly grounded (no resistor) for maximum gain.

Example small RF amplifier use (practical)

  • Typical single‑stage VHF preamp:
    • VDD: 6–12 V (respect absolute max)
    • Drain load: high‑Q choke or resistor with RF choke to isolate DC
    • Gate1 bias: ~0 V via 100 kΩ to the source (or mid bias per datasheet recommended point)
    • Gate2 used for AGC: biased through resistor divider with bypass cap for DC decoupling
    • Source: small resistor 10–100 Ω for stability, bypassed for RF if higher gain desired
    • Output matching: L‑C network tuned to band, compensate for Cgd/Cgs

(Adjust resistor and choke values to meet the datasheet’s recommended bias point where gm is adequate and ID within limits.)

TO-72 Metal Can Pinout (Top View – looking at bottom of can)

When viewing the transistor from below (with the pins pointing toward you and the tab oriented correctly):

  • Pin 1 (Source): Connect to ground via a resistor or directly.
  • Pin 2 (Gate 1): RF input or oscillator input. This is the sensitive control gate.
  • Pin 3 (Gate 2): AGC control voltage input.
  • Pin 4 (Drain): RF output. Connect to VDD via a tuned LC circuit.

Important: The metal case is sometimes internally connected to the source (Pin 1) or left floating. Check the specific manufacturer's datasheet; if grounded, it provides shielding.

Pinout Conversion Note

If replacing a 3SK41 (TO-72) with a BF998 (SOT-143):

  • BF998 Pin 1 (Source) = 3SK41 Pin 1
  • BF998 Pin 2 (Gate 2) = 3SK41 Pin 2
  • BF998 Pin 3 (Drain) = 3SK41 Pin 4
  • BF998 Pin 4 (Gate 1) = 3SK41 Pin 3

Do not assume direct drop-in. Always verify bias voltages. Part 2: Absolute Maximum Ratings (Ta = 25°C)

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