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onsemi KSC5402DTF
- Part No.:
- KSC5402DTF
- Manufacturer:
- onsemi
- Category:
- Single Bipolar Transistors
- Package:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Datasheet:
-
KSC5402DTF.pdf
- Description:
- TRANS NPN 525V 2A TO-252AA
- Quantity:
- Payment:
- Shipping:
Inventory:2
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Product details
Overview
KSC5402DTF from ON Semiconductor is a high-voltage NPN planar silicon power transistor with built-in free-wheeling diode, rated for 450 V VCEO, 2 A DC collector current, and 50 W power dissipation in TO-220 package-designed for electronic ballast and high-speed switching applications in lighting control systems.
For engineers reviewing the KSC5402DTF datasheet, pinout, applications, or equivalent options, this page delivers verified electrical specs, thermal characteristics, switching timing data, safe operating area details, and validated alternative options for legacy design support and obsolescence mitigation.
Technical Context
This device integrates a monolithic NPN bipolar junction transistor with an integrated anti-parallel diode on a single die, enabling self-commutated inductive load switching without external diode placement. Its wide SOA supports operation at high voltage (up to 450 V) and moderate current (2 A DC) with controlled saturation behavior across temperature.
Switching performance is characterized by sub-microsecond turn-off time (0.95–1.25 μs at 25°C), low dynamic saturation voltage (e.g., 1.5 V at 3 μs under 1 A/200 mA drive), and fast forward recovery (480–540 ns), making it suitable for resonant and quasi-resonant electronic ballast topologies requiring precise timing and low conduction loss.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCEO | 450 V - Maximum sustainable collector-emitter voltage before breakdown; enables use in 277 V AC line-fed ballasts with margin. |
| IC (DC) | 2 A - Continuous collector current rating; defines steady-state power handling in linear or PWM-regulated stages. |
| PC (TO-220) | 50 W - Power dissipation limit at TC = 25°C; requires heatsinking for sustained operation above ~10 W ambient. |
| tOFF | 0.95–1.25 μs - Measured at 25°C with 1 A IC, 200 mA IB1, 150 mA IB2, 300 V VCC; critical for minimizing switching losses in 20–50 kHz ballast drivers. |
| hFE (IC=0.4 A) | 14–29 - DC current gain range at 25°C; determines base drive requirements for reliable saturation in hard-switched configurations. |
| VF (diode) | 0.86–1.5 V - Forward voltage of integrated diode at 1 A; reduces component count and PCB footprint vs. discrete diode solutions. |
| RθJC | 2.5 °C/W - Junction-to-case thermal resistance (TO-220); enables thermal modeling for heatsink selection and reliability prediction. |
Pinout & Package
Package: TO-220 (3-lead, straight lead form). Mounting surface is electrically connected to collector (Case = Collector).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Emitter) | Emitting terminal for majority carriers | Low-impedance return path; connects to ground or low-side switch node in half-bridge configurations. |
| 2 (Collector) | Current-sinking terminal | Electrically tied to package tab; must be isolated from heatsink unless heatsink is at same potential as collector rail. |
| 3 (Base) | Control input for minority carrier injection | Requires current-limited drive (max 1 A DC); base resistor selection must ensure full saturation while avoiding overdrive-induced storage delay. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated free-wheeling diode | Eliminates need for external flyback diode in inductive load circuits, reducing BOM count and layout complexity in compact ballast designs. |
| Wide Safe Operating Area (SOA) | Supports simultaneous high voltage (450 V) and moderate current (2 A) without secondary breakdown-enables robust operation during transient overload conditions. |
| Small variance in storage time | Ensures consistent turn-off behavior across production lots and temperature (25–125°C), improving timing predictability in frequency-controlled ballasts. |
| High-speed switching capability | Sub-microsecond tOFF and nanosecond-scale tON/tF enable efficient operation up to 50 kHz, matching typical electronic fluorescent lamp (EFL) driver frequencies. |
| Two-package availability | D-PAK and TO-220 variants allow trade-offs between thermal performance (TO-220: 50 W, RθJC = 2.5 °C/W) and board space (D-PAK: surface-mount compatibility). |
Applications
| Electronic Ballast Control | AC-DC Lighting Driver |
|---|---|
|
Use Scenario: Driving resonant LC tank in instant-start fluorescent lamp ballasts operating at 20–50 kHz. IC Role / Device Role / Timing Role: High-voltage NPN switch controlling primary current flow; integrated diode provides path for inductive energy recovery during off-cycle. Use Value: Reduces component count by eliminating external flyback diode while maintaining fast switching (<1.25 μs tOFF) and stable SOA under 450 V stress. |
Use Scenario: Half-bridge switching stage in LED driver power supplies with universal AC input (90–305 V AC). IC Role / Device Role / Timing Role: Low-side switch in asymmetrical half-bridge topology; handles 2 A continuous current with minimal VCE(sat) drift over temperature. Use Value: Enables compact thermal design via 50 W TO-220 power rating and 2.5 °C/W RθJC, supporting >85% efficiency at 35 kHz switching. |
| Inductive Load Switching | High-Voltage Relay Replacement |
|
Use Scenario: Solid-state replacement for electromechanical relays controlling solenoids or transformers in industrial control panels. IC Role / Device Role / Timing Role: Main power switch with built-in diode clamping; manages stored inductive energy during de-energization. Use Value: Eliminates snubber networks and external diodes, simplifying circuit design while ensuring <1.4 μs tOFF at 125°C for responsive control. |
Use Scenario: High-reliability switching of 277 V AC lighting circuits in commercial building automation systems. IC Role / Device Role / Timing Role: Isolated high-voltage switch replacing mechanical contactors; operates with galvanically separated gate drive. Use Value: Delivers 450 V VCEO margin over 277 V RMS line, enabling long-term reliability without derating in harsh thermal environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-voltage NPN power transistor applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| STN1050 | Higher VCEO (1050 V), lower IC (1.5 A DC), no integrated diode, TO-220 package. | Used in higher-voltage SMPS and motor drives where external diode is acceptable and voltage margin >1 kV is required. | Select when system requires >600 V blocking capability and can accommodate separate diode layout; not drop-in due to missing diode and different gain profile. |
| MJD122G | Lower VCEO (100 V), higher IC (8 A DC), no integrated diode, DPAK package. | Targeted at low-voltage, high-current switching (e.g., automotive solenoid drivers) where voltage stress is <100 V. | Choose only for <100 V applications needing higher current capacity; incompatible for 450 V ballast use due to insufficient voltage rating. |
Compared with KSC5402DTF, STN1050 offers greater voltage headroom but lacks the integrated diode and has reduced current capability, while MJD122G provides higher current but fails to meet the 450 V requirement-making KSC5402DTF uniquely suited for mid-voltage, diode-integrated ballast switching where both voltage and integration matter.
Availability
KSC5402DTF is available at Aetrix Electronics and suitable for electronic ballast control, AC-DC lighting drivers, inductive load switching, and high-voltage relay replacement requiring stable component supply amid legacy product transitions.
Supply support for KSC5402DTF 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 is a global semiconductor manufacturer specializing in power management, analog, sensor, and logic devices for automotive, industrial, cloud, and communications markets.
KSC5402DTF belongs to ON Semiconductor's legacy high-voltage bipolar power transistor family, originally developed by Fairchild for energy-efficient lighting control and designed to deliver robust switching performance in thermally constrained electronic ballast applications.
FAQ
What is the maximum collector-emitter voltage rating for KSC5402DTF?
The KSC5402DTF has a VCEO rating of 450 V, meaning it can sustain up to 450 V between collector and emitter with base open before breakdown occurs. This rating is confirmed in the Absolute Maximum Ratings table and applies at TA = 25°C. Derating is required above 25°C per the thermal curves in the datasheet, and actual system design must include safety margin for transients and ripple.
Does KSC5402DTF include an integrated diode, and what is its forward voltage?
Yes, the KSC5402DTF integrates a monolithic free-wheeling diode across collector and emitter. Its forward voltage (VF) is specified as 0.86–1.5 V at 1 A and 25°C, with lower values (0.6–0.65 V) observed at 125°C. This diode eliminates the need for an external flyback diode in inductive switching applications such as electronic ballasts.
Is KSC5402DTF still recommended for new designs?
No-KSC5402DTF is marked "DISCONTINUED" and "NOT RECOMMENDED FOR NEW DESIGN" in the official ON Semiconductor documentation. It remains available for legacy support and repair, but designers should consult ON Semiconductor for approved replacements or modern alternatives with enhanced efficiency, thermal performance, or integrated features.
What package options are available for KSC5402DTF?
KSC5402DTF is offered in TO-220 package (as indicated by the "TF" suffix), with thermal resistance RθJC = 2.5 °C/W and PC = 50 W at TC = 25°C. The related KSC5402D variant uses D-PAK packaging (RθJC = 4.17 °C/W, PC = 30 W). Pinout and internal structure are identical between packages; only mechanical and thermal characteristics differ.
How does the storage time of KSC5402DTF vary with temperature and current?
KSC5402DTF exhibits small variance in storage time (tSTG): 0.56–0.65 μs at 25°C and 1.1–1.2 μs at 25°C under higher drive (IC = 1 A, IB1 = 200 mA), increasing to 1.35 μs at 125°C. This tight spread ensures predictable turn-off timing across operating conditions-critical for stable frequency control in resonant ballast circuits.
KSC5402DTF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-252-3, DPAK (2 Leads + Tab), SC-63
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Transistor Type:
- NPN
- Current - Collector (Ic) (Max):
- 2 A
- Voltage - Collector Emitter Breakdown (Max):
- 525 V
- Vce Saturation (Max) @ Ib, Ic:
- 750mV @ 200mA, 1A
- Current - Collector Cutoff (Max):
- 250µA
- DC Current Gain (hFE) (Min) @ Ic, Vce:
- 6 @ 1A, 1V
- Power - Max:
- 30 W
- Frequency - Transition:
- 11MHz
- Operating Temperature:
- 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-252AA
KSC5402DTF FAQ
1.How can I place an order for KSC5402DTF through Aetrix?
Please submit a Request for Quotation (RFQ) for KSC5402DTF 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 KSC5402DTF reliable?
The price and inventory of KSC5402DTF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for KSC5402DTF is usually 5 days.
3.What payment methods are accepted for KSC5402DTF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for KSC5402DTF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for KSC5402DTF?
KSC5402DTF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your KSC5402DTF 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 KSC5402DTF?
For technical support, including KSC5402DTF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your KSC5402DTF requirements.
6.How does Aetrix verify that KSC5402DTF is sourced from the original manufacturer or authorized distributors?
All KSC5402DTF 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 KSC5402DTF meets industry standards.
7.What is the process for return or replacement of KSC5402DTF?
All KSC5402DTF units undergo pre-shipment inspection (PSI). If there is an issue with KSC5402DTF, 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 KSC5402DTF part is unused and in its original packaging.
Return procedure for KSC5402DTF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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