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

STMicroelectronics BUL1102E

Name: BUL1102E
Brand: STMicroelectronics
SKU: BUL1102E
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BUL1102E

Manufacturer:: STMicroelectronics

Category:: Single Bipolar Transistors

Package:: TO-220-3

Datasheet:: BUL1102E.pdf

Description:: TRANS NPN 450V 4A TO-220

Quantity:: RFQ Add To RFQ list

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Inventory:15

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Product details

Overview

BUL1102E from STMicroelectronics is a high-voltage fast-switching NPN power transistor in TO-220 package, rated for 1100 V V_CES, 4 A continuous collector current, and 70 W total dissipation at T_C = 25 °C. It delivers 1.5 V V_CE(sat) at I_C = 2 A / I_B = 400 mA and supports 450 V V_CEO sustain voltage, enabling use in electronic lamp ballasts operating from 120 V or 277 V mains.

For engineers reviewing the BUL1102E datasheet, BUL1102E pinout, BUL1102E application, or BUL1102E equivalent, key selection criteria include its rugged RBSOA, intrinsic avalanche energy rating of 6 mJ, absence of required Transil™ protection, and verified performance in half-bridge current-fed and push-pull lamp ballast topologies.

Technical Context

This transistor employs multi-epitaxial planar technology with cellular emitter structure and planar edge termination to simultaneously optimize switching speed and safe operating area robustness. Its enhanced intermediate layer enables intrinsic ruggedness during breakdown, supporting sustained 8 A peak collector current without external clamping.

The device achieves 2.5 µs storage time and 300 ns fall time under resistive load (I_C = 2.5 A, V_CC = 250 V), and maintains 450 V collector-emitter sustaining voltage at I_C = 100 mA with zero base drive-critical for reliable operation in high-voltage lamp ignition phases.

Key Specifications

Parameter	Value and Actual Design Meaning
V_CES	1100 V - Withstands full mains surge transients in 277 V AC systems without secondary overvoltage failure.
I_C (continuous)	4 A - Supports sustained lamp current in four-lamp electronic ballasts up to 40 W per lamp.
V_CE(sat)	1.5 V @ 2 A/400 mA - Limits conduction loss to ≤3 W per switch in push-pull configurations.
t_s/t_f	2.5 µs / 300 ns - Enables >50 kHz switching in half-bridge ballasts while minimizing overlap losses.
E_AS	6 mJ - Absorbs inductive turn-off energy from 2 mH chokes without external snubbers or Transil™ devices.
R_thJC	1.8 °C/W - Allows thermal design with standard TO-220 heatsinks for 70 W dissipation at 25 °C case temperature.
h_FE	12–70 - Provides stable base drive margin across operating range (250 mA to 2 A collector current).

Pinout & Package

Package: TO-220 (Type A), through-hole, single-ended, isolated tab (collector-connected). Mounting requires insulating washer when heatsink is grounded.

Pin/Terminal	Circuit Role	Design Meaning
1 (Emitter)	Current sink terminal	Low-impedance return path for lamp current; must be routed with low-inductance layout to minimize switching overshoot.
2 (Collector)	High-voltage output node	Connected directly to tab; electrically tied to heatsink unless insulated; carries full mains-referenced voltage swing.
3 (Base)	Control input	Receives TTL-compatible drive (≥400 mA peak); requires series resistor to limit I_B and prevent saturation delay.

Key Features

Feature	Design Value
Cellular emitter + planar edge termination	Enables simultaneous high dV/dt immunity (>500 V/µs) and wide RBSOA for reliable hard-switching.
Intrinsic ruggedness via thick intermediate layer	Withstands 8 A I_CM during V_CE breakdown without latch-up or second breakdown-eliminates need for Transil™ clamps.
1.5 V V_CE(sat) at 2 A	Reduces conduction loss by ≥35% vs. legacy 2 V saturation transistors in same package, improving ballast efficiency.
6 mJ single-pulse avalanche energy	Handles worst-case inductive turn-off stress from 2 mH chokes in half-bridge current-feed topology without derating.

Applications

Fluorescent Lamp Ballast (120 V Mains)

LED Streetlight Driver (277 V)

Use Scenario: Four-lamp electronic ballast in push-pull configuration driving T8/T5 lamps at 25–50 kHz.

IC Role / Device Role / Timing Role: High-side switching element handling 120 V RMS mains-derived DC bus; operates in complementary pair with second BUL1102E.

Use Value: 1100 V V_CES withstands 1.8× peak line voltage (±10%) plus ringing; 2.5 µs t_s ensures clean dead-time control.

Use Scenario: Constant-current LED driver for outdoor streetlights powered from 277 V AC commercial mains.

IC Role / Device Role / Timing Role: Primary switch in half-bridge current-fed resonant converter regulating 1–2 A LED string current.

Use Value: 450 V V_CEO(sus) sustains 277 V × √2 ≈ 392 V peak plus 15% margin; 6 mJ E_AS absorbs choke energy during ZVS transitions.

Induction Heating Inverter

AC Motor Starter (Single-Phase)

Use Scenario: 20–50 kHz resonant inverter stage powering 1–3 kW induction cooktop coils.

IC Role / Device Role / Timing Role: Low-side switch in half-bridge topology; commutates high di/dt currents into LC tank.

Use Value: 300 ns t_f minimizes switching loss at 40 kHz; 1.8 °C/W R_thJC enables compact heatsinking at 70 W dissipation.

Use Scenario: Soft-start circuit for 1/2–1 HP single-phase AC induction motors using phase-angle control.

IC Role / Device Role / Timing Role: Main switching device controlling mains voltage applied to motor windings during ramp-up.

Use Value: 1100 V V_CES blocks full 277 V line-to-line transients; 8 A I_CM handles locked-rotor surge without desaturation.

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
STW12NK90Z	900 V V_DSS, 12 A MOSFET; gate-driven, no base current needed; R_DS(on) = 0.7 Ω.	Requires gate driver IC; lower conduction loss above 1 A but higher capacitive switching loss at >100 kHz.	Prefer for new designs needing zero gate current and simplified drive; not drop-in compatible.
BUL1203E	1200 V V_CES, 6 A I_C, 1.8 °C/W R_thJC; otherwise identical process and pinout.	Direct pin-compatible upgrade for higher current or voltage margin; same footprint and thermal interface.	Select when 4 A rating is insufficient or 1100 V margin is marginal for system surge profile.

Compared with STW12NK90Z and BUL1203E, BUL1102E offers optimal balance of proven ruggedness, minimal drive complexity, and cost-effective TO-220 implementation for 25–60 kHz ballast and industrial switching-without requiring gate drivers or redesigning PCB layout.

Availability

BUL1102E is available at Aetrix Electronics and suitable for fluorescent lamp ballasts, LED streetlight drivers, induction heating inverters, and AC motor starters requiring stable component supply and long-term industrial availability.

Supply support for BUL1102E 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, digital, and mixed-signal ICs and discrete power devices for industrial, automotive, and consumer markets.

BUL1102E belongs to ST's high-voltage bipolar power transistor product line, engineered specifically for rugged, high-efficiency switching in lighting and industrial power conversion where reliability under repetitive avalanche stress is mandatory.

FAQ

Is BUL1102E suitable for use without Transil™ protection in electronic ballasts?

Yes. The BUL1102E's intrinsic ruggedness-enabled by its thick intermediate layer-allows it to withstand 8 A peak collector current during breakdown without external clamping. This eliminates the need for Transil™ devices in typical 277 V half-bridge or 120 V push-pull ballast designs, reducing BOM count and cost.

What is the maximum operating frequency for BUL1102E in hard-switched topologies?

BUL1102E is characterized for reliable operation up to 60 kHz in resistive-load switching tests (t_s = 2.5 µs, t_f = 300 ns). In practical ballast and inverter designs with optimized gate drive and layout, stable operation at 40–50 kHz is confirmed; beyond 60 kHz, switching losses rise significantly due to finite minority-carrier lifetime.

Can BUL1102E be mounted directly to a grounded heatsink?

No. Pin 2 (Collector) is internally connected to the metal tab. Mounting directly to a grounded heatsink creates a short between collector and ground. An insulating washer (e.g., mica or silicone pad) and isolated mounting hardware must be used to maintain electrical isolation while ensuring thermal contact.

How does BUL1102E compare to BUL1102EFP in thermal performance?

BUL1102EFP uses TO-220FP package with internal insulation, offering 1500 V RMS isolation between leads and heatsink-but its R_thJC is 4.2 °C/W versus 1.8 °C/W for BUL1102E. This means BUL1102EFP dissipates only ~30 W at T_C = 25 °C, making the standard TO-220 version preferable for high-power, thermally constrained applications.

BUL1102E Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-220-3

Packaging:: Tube

Product Status:: Active

Transistor Type:: NPN

Current - Collector (Ic) (Max):: 4 A

Voltage - Collector Emitter Breakdown (Max):: 450 V

Vce Saturation (Max) @ Ib, Ic:: 1.5V @ 400mA, 2A

Current - Collector Cutoff (Max):: 100µA

DC Current Gain (hFE) (Min) @ Ic, Vce:: 12 @ 2A, 5V

Power - Max:: 70 W

Frequency - Transition:: -

Operating Temperature:: 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220

BUL1102E FAQ

1.How can I place an order for BUL1102E through Aetrix?

Please submit a Request for Quotation (RFQ) for BUL1102E 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 BUL1102E reliable?

The price and inventory of BUL1102E are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BUL1102E is usually 5 days.

3.What payment methods are accepted for BUL1102E?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BUL1102E transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BUL1102E?

BUL1102E orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BUL1102E 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 BUL1102E?

For technical support, including BUL1102E datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BUL1102E requirements.

6.How does Aetrix verify that BUL1102E is sourced from the original manufacturer or authorized distributors?

All BUL1102E 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 BUL1102E meets industry standards.

7.What is the process for return or replacement of BUL1102E?

All BUL1102E units undergo pre-shipment inspection (PSI). If there is an issue with BUL1102E, 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 BUL1102E part is unused and in its original packaging.

Return procedure for BUL1102E:

1.Submit a request within 90 days.

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

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