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

onsemi KSC5603D

Name: KSC5603D
Brand: onsemi
SKU: KSC5603D
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: KSC5603D

Manufacturer:: onsemi

Category:: Single Bipolar Transistors

Package:: TO-220-3

Datasheet:: KSC5603D.pdf

Description:: TRANS NPN 800V 3A TO-220-3

Quantity:: RFQ Add To RFQ list

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Product details

Overview

KSC5603D from ON Semiconductor is a high-voltage NPN silicon planar transistor in TO-220 package, rated for 800 V V_CEO, 3 A DC collector current, and 100 W power dissipation at T_C = 25°C. It integrates a built-in freewheeling diode and delivers fast switching with t_STG as low as 0.60 μs under inductive load, making it suitable for electronic ballast and high-speed power switch applications.

For engineers reviewing the KSC5603D datasheet, pinout, applications, or equivalent options, key selection criteria include its 1600 V V_CBO rating, wide SOA, low storage time variance, and compatibility with 15–125 V switching rails in fluorescent lamp control and industrial SMPS designs.

Technical Context

The KSC5603D employs a planar epitaxial structure optimized for high-voltage switching with robust secondary breakdown immunity. Its integrated freewheeling diode enables self-contained inductive energy recirculation without external components.

Switching performance is characterized under both resistive (20 μs pulse, <10% duty) and inductive (V_Z = 300 V, L_C = 200 μH) conditions, with validated t_F down to 140 ns and t_C as low as 170 ns at T_J = 25°C - critical for minimizing cross-conduction losses in half-bridge topologies.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CEO	800 V - supports operation in 600 V AC line-derived bus systems with margin for transient overvoltage
I_C (DC)	3 A - enables continuous conduction mode operation in 100–200 W electronic ballasts
P_C @ T_C=25°C	100 W - allows direct mounting to heatsink without forced air cooling in compact fixtures
t_STG (inductive)	0.60–1.00 μs - reduces stored charge delay during turn-off, improving efficiency in high-frequency (>25 kHz) lamp ignition
R_θJC	1.25 °C/W - ensures junction temperature stays ≤150°C with case temp ≤125°C under full load
h_FE @ I_C=0.4 A	20–35 - provides stable base drive design margin across temperature (25°C to 125°C)
V_F (diode)	0.76–1.50 V @ I_F=0.4–1 A - minimizes freewheeling conduction loss in flyback recovery paths

Pinout & Package

Package: TO-220 three-lead plastic package with isolated tab (pin 2 = Collector, electrically connected to tab). Standard JEDEC TO-220AB footprint, 16.51 mm × 10.16 mm × 4.10 mm body dimensions, 1.25 °C/W junction-to-case thermal resistance.

Pin/Terminal	Circuit Role	Design Meaning
1	Base	Low-impedance control input requiring 50–250 mA peak drive for full saturation in switching applications
2	Collector	Main high-voltage power terminal; electrically tied to metal tab - requires insulated mounting in non-ground-referenced topologies
3	Emitter	Reference node for base drive and load return; carries full switched current and must be routed with low-inductance layout

Key Features

Feature	Design Value
Built-in freewheeling diode	Eliminates need for external catch diode in inductive load circuits, reducing BOM count and PCB area in ballast drivers
Wide Safe Operating Area (SOA)	Supports linear-mode operation up to 800 V × 3 A with no second breakdown limitation - essential for dimmable ballast soft-start
Small variance in storage time	±0.1 μs variation across production lot ensures consistent timing in synchronized multi-lamp systems
High-speed switching	Sub-microsecond t_STG and t_F enable >50 kHz operation while maintaining <5% switching loss in 100 W systems

Applications

Electronic Ballast Control	Industrial SMPS Primary Switch
Use Scenario: Driving resonant LC tank in instant-start fluorescent lamp ballasts operating at 25–65 kHz. IC Role / Device Role / Timing Role: Main high-voltage switching transistor handling 800 V bus and 3 A peak lamp current. Use Value: Integrated freewheeling diode and low t_STG reduce component count and improve lamp ignition reliability across temperature.	Use Scenario: Primary-side switch in 150 W offline flyback converter for industrial control power supplies. IC Role / Device Role / Timing Role: High-voltage NPN switch controlling energy transfer from 800 V DC bus to transformer primary. Use Value: 1600 V V_CBO rating and 1.25 °C/W R_θJC allow robust operation with minimal derating in sealed enclosures.
AC Motor Starter Circuit	Induction Heater Half-Bridge
Use Scenario: Phase-controlled start-up circuit for single-phase induction motors in HVAC blowers. IC Role / Device Role / Timing Role: High-voltage switch enabling zero-crossing-triggered voltage ramp to limit inrush current. Use Value: Wide SOA and stable h_FE across temperature ensure predictable gate drive requirements during extended start cycles.	Use Scenario: Low-side switch in 20–50 kHz half-bridge resonant inverter for small-appliance induction heating. IC Role / Device Role / Timing Role: Fast-turnoff NPN transistor managing high di/dt currents with integrated diode clamping. Use Value: Sub-μs t_STG and t_F minimize dead-time losses while built-in diode prevents reverse recovery spikes.

Electronic Ballast Control

Industrial SMPS Primary Switch

Use Scenario: Driving resonant LC tank in instant-start fluorescent lamp ballasts operating at 25–65 kHz.

IC Role / Device Role / Timing Role: Main high-voltage switching transistor handling 800 V bus and 3 A peak lamp current.

Use Value: Integrated freewheeling diode and low t_STG reduce component count and improve lamp ignition reliability across temperature.

Use Scenario: Primary-side switch in 150 W offline flyback converter for industrial control power supplies.

IC Role / Device Role / Timing Role: High-voltage NPN switch controlling energy transfer from 800 V DC bus to transformer primary.

Use Value: 1600 V V_CBO rating and 1.25 °C/W R_θJC allow robust operation with minimal derating in sealed enclosures.

AC Motor Starter Circuit

Induction Heater Half-Bridge

Use Scenario: Phase-controlled start-up circuit for single-phase induction motors in HVAC blowers.

IC Role / Device Role / Timing Role: High-voltage switch enabling zero-crossing-triggered voltage ramp to limit inrush current.

Use Value: Wide SOA and stable h_FE across temperature ensure predictable gate drive requirements during extended start cycles.

Use Scenario: Low-side switch in 20–50 kHz half-bridge resonant inverter for small-appliance induction heating.

IC Role / Device Role / Timing Role: Fast-turnoff NPN transistor managing high di/dt currents with integrated diode clamping.

Use Value: Sub-μs t_STG and t_F minimize dead-time losses while built-in diode prevents reverse recovery spikes.

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage NPN switching transistor applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
ST13007D	V_CEO = 400 V, I_C = 8 A, no integrated diode, TO-220 package	Limited to lower-voltage (<400 V) SMPS; requires external flyback diode	Select when higher current and lower V_CEO suffice and diode integration is not required
MJE13009	V_CEO = 400 V, I_C = 12 A, no integrated diode, TO-220 package	Higher current capability but insufficient for 600 V AC line-derived 800 V bus applications	Prefer for high-current, medium-voltage motor drives where KSC5603D's voltage rating exceeds requirement

Compared with ST13007D and MJE13009, the KSC5603D uniquely combines 800 V V_CEO, integrated freewheeling diode, and sub-microsecond storage time - making it irreplaceable in high-voltage electronic ballast and resonant converter designs where voltage margin and diode integration are mandatory.

Availability

KSC5603D is available at Aetrix Electronics and suitable for electronic ballast control, industrial SMPS primary switching, and AC motor starter circuits requiring stable component supply and long-term manufacturing continuity.

Supply support for KSC5603D 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

ON Semiconductor (formerly Fairchild Semiconductor) is a global semiconductor supplier specializing in power management, analog, sensor, and logic devices for automotive, industrial, and consumer applications.

The KSC5603D belongs to ON Semiconductor's high-voltage bipolar transistor product line, engineered specifically for energy-efficient lighting control and rugged industrial switching where high breakdown voltage, fast switching, and integrated protection are essential.

FAQ

What is the maximum collector-emitter voltage rating for the KSC5603D?

The KSC5603D has a guaranteed minimum V_CEO of 800 V, with typical values reaching 870 V at I_C = 5 mA and T_A = 25°C. This rating allows safe operation in 600 V AC line-derived DC bus applications with sufficient margin for surge transients per IEC 61000-4-5.

Does the KSC5603D include an integrated freewheeling diode?

Yes, the KSC5603D integrates a built-in freewheeling diode as explicitly stated in its features and confirmed by electrical test data for V_F (0.76–1.50 V). This diode is monolithically formed within the same die and shares the emitter and collector terminals - eliminating need for external diode placement in inductive load circuits.

What is the thermal resistance from junction to case for the KSC5603D?

The KSC5603D has a specified R_θJC of 1.25 °C/W, measured under standard JEDEC conditions. This value enables accurate junction temperature estimation when mounted to a heatsink with known thermal interface resistance, supporting reliable thermal design for continuous 100 W power dissipation at T_C = 25°C.

Can the KSC5603D be used in inductive switching applications like motor control?

Yes, the KSC5603D is qualified for inductive load switching, with published t_STG, t_F, and t_C data at V_Z = 300 V and L_C = 200 μH. Its wide SOA and built-in diode make it suitable for AC motor starter circuits and other inductive switching applications where voltage overshoot and stored charge management are critical.

What is the DC current gain (h_FE) range of the KSC5603D at room temperature?

At T_A = 25°C, the KSC5603D exhibits h_FE = 20–35 when tested at V_CE = 3 V and I_C = 0.4 A. This range is confirmed in the Electrical Characteristics table and supports stable base drive design for linear and switching modes without requiring gain binning.

KSC5603D Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: TO-220-3

Packaging:: Bulk

Product Status:: Obsolete

Transistor Type:: NPN

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

Voltage - Collector Emitter Breakdown (Max):: 800 V

Vce Saturation (Max) @ Ib, Ic:: 2.5V @ 200µA, 1A

Current - Collector Cutoff (Max):: 100µA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 20 @ 400mA, 3V

Power - Max:: 100 W

Frequency - Transition:: 5MHz

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220-3

KSC5603D FAQ

1.How can I place an order for KSC5603D through Aetrix?

Please submit a Request for Quotation (RFQ) for KSC5603D 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 KSC5603D reliable?

The price and inventory of KSC5603D are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSC5603D is usually 5 days.

3.What payment methods are accepted for KSC5603D?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSC5603D transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for KSC5603D?

KSC5603D orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your KSC5603D 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 KSC5603D?

For technical support, including KSC5603D datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSC5603D requirements.

6.How does Aetrix verify that KSC5603D is sourced from the original manufacturer or authorized distributors?

All KSC5603D 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 KSC5603D meets industry standards.

7.What is the process for return or replacement of KSC5603D?

All KSC5603D units undergo pre-shipment inspection (PSI). If there is an issue with KSC5603D, 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 KSC5603D part is unused and in its original packaging.

Return procedure for KSC5603D:

1.Submit a request within 90 days.

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

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