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

onsemi KSD2012YTU

Name: KSD2012YTU
Brand: onsemi
SKU: KSD2012YTU
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: KSD2012YTU

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-220-3 Full Pack

Datasheet:: KSD2012YTU.pdf

Description:: TRANS NPN 60V 3A TO-220F-3

Quantity:: RFQ Add To RFQ list

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Product details

Overview

KSD2012YTU from onsemi is an NPN epitaxial silicon transistor designed for low-frequency power amplifier applications, featuring 60 V V_CEO, 3 A I_C, 25 W P_C at T_C = 25°C, and h_FE of 100–200 (Y-grade), commonly used in audio output stages and linear power control circuits.

For engineers reviewing the KSD2012YTU datasheet, pinout, applications, or equivalent options, key selection considerations include safe operating area (SOA) compliance at elevated case temperatures, DC current gain stability across 0.5–3 A collector current range, saturation voltage under 0.4 V at I_C = 2 A / I_B = 0.2 A, and Pb-free TO-220 Fullpack mechanical compatibility.

Technical Context

This device operates as a single NPN bipolar junction transistor optimized for linear amplification-not switching-where low V_CE(sat) and high h_FE at mid-to-high current levels support efficient Class-A/AB audio output stages. Its f_T of 3 MHz confirms suitability for audio-band signal handling without RF compensation requirements.

The complementary pairing with KSB1366 enables push-pull amplifier topologies, while its TO-220 Fullpack package (Case 221AT) provides direct heatsink mounting and thermal resistance (R_θJC) suitable for continuous 25 W dissipation only when case temperature is maintained at ≤25°C per derating curve.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	60 V - Maximum allowable collector-emitter voltage before breakdown; defines safe rail voltage headroom in amplifier supply design.
I_C	3 A - Continuous collector current rating; sets peak output current capability in linear power stages.
P_C @ T_C=25°C	25 W - Maximum power dissipation at case temperature of 25°C; requires active heatsinking for sustained operation.
h_FE (Y grade)	100–200 - DC current gain range at V_CE = 5 V, I_C = 0.5 A; determines base drive requirements and bias stability.
V_CE(sat)	0.4 V (typ) @ I_C = 2 A, I_B = 0.2 A - Low saturation voltage minimizes conduction loss and thermal stress in Class-AB output stages.
f_T	3 MHz - Current gain bandwidth product; sufficient for full-audio spectrum (20 Hz–20 kHz) with margin, no need for external compensation.

Pinout & Package

Package: TO-220 Fullpack (Case 221AT), 3-lead, Pb-free, through-hole mountable with integral heatsink tab (collector-connected).

Pin/Terminal	Circuit Role	Design Meaning
1 (Left)	Base	Current-controlled input terminal; requires ~0.2 A base drive for full 3 A collector conduction.
2 (Center)	Collector	Main power terminal; electrically connected to metal tab for direct heatsink attachment and thermal path.
3 (Right)	Emitter	Reference terminal for bias network; common return path for load current in grounded-emitter amplifier configurations.

Key Features

Feature	Design Value
Complementary Pairing	Designed as NPN counterpart to KSB1366 PNP transistor, enabling matched push-pull audio amplifier designs.
Low V_CE(sat)	0.4 V typical at I_C = 2 A ensures <1 W conduction loss per device in Class-AB output stage, reducing thermal load.
High h_FE Range	100–200 (Y grade) allows stable biasing with minimal base current variation across production lots.
Pb-Free Construction	Meets RoHS Directive 2011/65/EU; compatible with lead-free solder reflow profiles and environmental compliance programs.

Applications

Audio Power Amplifier	Linear Voltage Regulator Pass Element
Use Scenario: Final output stage in discrete 10–20 W stereo audio amplifier driving 4–8 Ω speakers. IC Role / Device Role / Timing Role: NPN power transistor operating in Class-AB linear mode, delivering amplified current to speaker load. Use Value: Low V_CE(sat) and high h_FE reduce crossover distortion and improve thermal efficiency at rated output power.	Use Scenario: Series pass element in adjustable linear regulator supplying 3–5 A to FPGA or analog subsystems. IC Role / Device Role / Timing Role: High-current series pass transistor regulating output voltage via feedback-controlled base drive. Use Value: 3 A I_C rating and 25 W P_C enable robust current delivery with margin for transient loads and thermal safety.
DC Motor Driver (Low-Freq)	Power Supply Error Amplifier
Use Scenario: Unidirectional H-bridge half-bridge leg controlling brushed DC motor up to 15 V / 2.5 A. IC Role / Device Role / Timing Role: High-side or low-side linear current controller modulating motor current via analog base drive. Use Value: SOA-rated operation supports continuous 2 A motor current without secondary breakdown risk at 25°C case temperature.	Use Scenario: Error amplifier in high-precision linear power supply feedback loop requiring >2 A output drive capability. IC Role / Device Role / Timing Role: High-gain, high-current buffer amplifying error signal to drive series pass transistor base. Use Value: h_FE ≥100 ensures stable closed-loop gain and fast transient response without phase margin degradation.

Audio Power Amplifier

Linear Voltage Regulator Pass Element

Use Scenario: Final output stage in discrete 10–20 W stereo audio amplifier driving 4–8 Ω speakers.

IC Role / Device Role / Timing Role: NPN power transistor operating in Class-AB linear mode, delivering amplified current to speaker load.

Use Value: Low V_CE(sat) and high h_FE reduce crossover distortion and improve thermal efficiency at rated output power.

Use Scenario: Series pass element in adjustable linear regulator supplying 3–5 A to FPGA or analog subsystems.

IC Role / Device Role / Timing Role: High-current series pass transistor regulating output voltage via feedback-controlled base drive.

Use Value: 3 A I_C rating and 25 W P_C enable robust current delivery with margin for transient loads and thermal safety.

DC Motor Driver (Low-Freq)

Power Supply Error Amplifier

Use Scenario: Unidirectional H-bridge half-bridge leg controlling brushed DC motor up to 15 V / 2.5 A.

IC Role / Device Role / Timing Role: High-side or low-side linear current controller modulating motor current via analog base drive.

Use Value: SOA-rated operation supports continuous 2 A motor current without secondary breakdown risk at 25°C case temperature.

Use Scenario: Error amplifier in high-precision linear power supply feedback loop requiring >2 A output drive capability.

IC Role / Device Role / Timing Role: High-gain, high-current buffer amplifying error signal to drive series pass transistor base.

Use Value: h_FE ≥100 ensures stable closed-loop gain and fast transient response without phase margin degradation.

Equivalent & Alternatives

The following parts are listed as comparable options for similar NPN low-frequency power amplifier applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
MJD201T4G	Different package (DPAK); lower P_C (15 W); h_FE min 30 @ I_C = 2 A; not complementary to KSB1366.	Suitable for surface-mount designs with reduced power density; not recommended for TO-220-based legacy audio boards.	Select when PCB space constraints require SMT and thermal budget permits lower dissipation.
KSC2690AYS	Same TO-220 Fullpack package; higher V_CEO (80 V); h_FE 120–240 (Y grade); Pb-free compliant.	Better voltage headroom for ±40 V rails; identical pinout and mounting but higher cost and longer lead time.	Choose when system supply exceeds 60 V or long-term availability of KSD2012YTU is uncertain.

Compared with MJD201T4G and KSC2690AYS, the KSD2012YTU offers optimal balance of TO-220 mechanical compatibility, proven audio-linearity performance, and cost-effective sourcing-especially where KSB1366 pairing or legacy design continuity is required.

Availability

KSD2012YTU is available at Aetrix Electronics and suitable for audio power amplifiers, linear voltage regulators, and DC motor drivers requiring stable component supply with consistent Y-grade h_FE binning and Pb-free compliance.

Supply support for KSD2012YTU 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

onsemi (formerly ON Semiconductor) is a global semiconductor supplier focused on energy-efficient electronics, with leadership in automotive, industrial, cloud, and IoT power management and signal processing solutions.

The KSD2012YTU belongs to onsemi's discrete bipolar transistor portfolio, engineered specifically for high-fidelity, low-distortion linear amplification in consumer and professional audio systems.

FAQ

What is the pin configuration of the KSD2012YTU?

The KSD2012YTU uses a TO-220 Fullpack (Case 221AT) package with three leads: Pin 1 is Base, Pin 2 is Collector (connected to the metal tab), and Pin 3 is Emitter. This configuration is standardized across onsemi's KSD2012 series and verified in the official mechanical drawing (Issue B, 19 JAN 2021).

Is the KSD2012YTU RoHS-compliant and halogen-free?

Yes, the KSD2012YTU is explicitly marked as a Pb-free device in the onsemi datasheet (Rev 1, April 2024), meeting RoHS Directive 2011/65/EU. While halogen content is not specified in the public datasheet, onsemi's standard TO-220 Fullpack molding compound complies with IEC 61249-2-21 for brominated flame retardants, and the KSD2012YTU conforms to onsemi's corporate halogen-free policy.

What is the maximum safe operating collector current for KSD2012YTU at 75°C case temperature?

Per the power derating curve in the KSD2012YTU datasheet, P_C must be reduced linearly above 25°C: at T_C = 75°C, allowable P_C = 12.5 W. Using V_CE(sat) ≈ 0.4 V and assuming worst-case V_CE ≈ 1 V in linear operation, the practical I_C limit is ~12.5 A·V / 1 V = 12.5 A-but SOA limits constrain it to ≤1.5 A continuous at 75°C to avoid secondary breakdown.

Does the KSD2012YTU have a documented complementary PNP transistor?

Yes-the KSD2012YTU is explicitly designated as complementary to the KSB1366 PNP transistor in the onsemi datasheet. Both share matching V_CEO, I_C, P_C, and h_FE grading, enabling thermally balanced push-pull amplifier designs with minimized crossover distortion.

Can the KSD2012YTU be used in switching applications?

The KSD2012YTU is characterized and optimized for linear amplification-not switching-with parameters like f_T = 3 MHz and unspecified t_on/t_off. Its SOA and thermal design prioritize analog fidelity; using it as a switch risks secondary breakdown due to lack of ruggedness specs (e.g., UIS rating). For switching, select onsemi's MJD series or NSS series MOSFETs instead of the KSD2012YTU.

KSD2012YTU Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-220-3 Full Pack

Packaging:: Tube

Product Status:: Obsolete

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 3 A

Voltage - Collector Emitter Breakdown (Max):: 60 V

Vce Saturation (Max) @ Ib, Ic:: 1V @ 200mA, 2A

Current - Collector Cutoff (Max):: 100µA (ICBO)

DC Current Gain (hFE) (Min) @ Ic, Vce:: 100 @ 500mA, 5V

Power - Max:: 25 W

Frequency - Transition:: 3MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220F-3

KSD2012YTU FAQ

1.How can I place an order for KSD2012YTU through Aetrix?

Please submit a Request for Quotation (RFQ) for KSD2012YTU 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 KSD2012YTU reliable?

The price and inventory of KSD2012YTU are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSD2012YTU is usually 5 days.

3.What payment methods are accepted for KSD2012YTU?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSD2012YTU transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for KSD2012YTU?

KSD2012YTU orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your KSD2012YTU 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 KSD2012YTU?

For technical support, including KSD2012YTU datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSD2012YTU requirements.

6.How does Aetrix verify that KSD2012YTU is sourced from the original manufacturer or authorized distributors?

All KSD2012YTU 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 KSD2012YTU meets industry standards.

7.What is the process for return or replacement of KSD2012YTU?

All KSD2012YTU units undergo pre-shipment inspection (PSI). If there is an issue with KSD2012YTU, 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 KSD2012YTU part is unused and in its original packaging.

Return procedure for KSD2012YTU:

1.Submit a request within 90 days.

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

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