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Taiwan Semiconductor Corporation BZW04-256
- Part No.:
- BZW04-256
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
BZW04-256.pdf
- Description:
- TVS DIODE 256VWM 414VC DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:5,770
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Product details
Overview
BZW04-256 from Taiwan Semiconductor is a unidirectional transient voltage suppressor (TVS) diode designed for high-energy surge protection in DC power rails and signal lines. It features a 256 V working stand-off voltage (VWM), 285–315 V breakdown voltage (VBR) at 1 mA, 400 W peak pulse power (10/1000 μs), clamping voltage of 414 V at 1 A peak impulse current, and operates across –55 °C to +175 °C junction temperature range - deployed in automotive lighting control modules and industrial PLC I/O protection.
For engineers reviewing the BZW04-256 datasheet, BZW04-256 pinout, BZW04-256 application, or BZW04-256 equivalent, key selection criteria include verified clamping performance at rated IPP, DO-41 package thermal derating behavior, unidirectional polarity marking, and AEC-Q101 qualification status for automotive-grade reliability validation.
Technical Context
The BZW04-256 operates as a silicon avalanche diode with fast response time (<1 ns) and low dynamic impedance during transient events. Its unidirectional configuration provides reverse-biased clamping only, requiring correct cathode-band orientation in PCB layout to protect downstream ICs from positive-going surges on supply lines.
It complies with ANSI/IEEE C62.35 for transient suppression testing and delivers 400 W peak pulse power under standardized 10/1000 μs waveform. Thermal performance is defined by RθJL = 60 °C/W and RθJA = 100 °C/W (on 10 mm lead length), supporting sustained operation up to 175 °C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 256 V - maximum continuous DC or RMS voltage the device blocks without clamping |
| VBR @ IT=1 mA | 285–315 V - guaranteed avalanche initiation range, defining minimum overvoltage threshold before conduction |
| VC @ IPP=1 A | 414 V - clamped voltage seen by protected circuit during 1 A transient, limiting stress on downstream components |
| PPK | 400 W - peak surge power handling capability per 10/1000 μs waveform, critical for ISO 7637-2 pulse 5a/b compliance |
| ID @ VWM | ≤1 μA - ultra-low leakage ensures minimal standby power loss and no false triggering near operating voltage |
| TJ max | +175 °C - extended junction temperature rating enables use in under-hood automotive environments and high-ambient industrial enclosures |
| Polarity | Cathode band marked - mandates correct orientation in series with protected line to ensure proper reverse-bias clamping action |
Pinout & Package
Package: DO-204AL (DO-41), axial-leaded, epoxy-molded case meeting UL 94V-0 flammability rating; terminals are pure tin-plated for J-STD-002 solderability.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Positive reference terminal | Connected to system ground or low-side return path; forms cathode-to-anode forward path during clamping |
| Cathode (banded end) | Surge input terminal | Connected to protected line (e.g., 24 V rail); conducts avalanche current to ground when voltage exceeds VBR |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified option available | Validated for automotive applications including engine control units and body electronics requiring stress-tested reliability |
| 400 W peak pulse power (10/1000 μs) | Meets ISO 7637-2 Pulse 5a (load dump) and IEC 61000-4-5 surge immunity requirements for industrial and transportation systems |
| Clamping voltage ≤414 V at 1 A | Ensures protected ICs (e.g., microcontrollers, CAN transceivers) remain below absolute maximum ratings during surge events |
| Reverse leakage ≤1 μA at 256 V | Prevents measurable power drain in always-on circuits and avoids false triggering in high-impedance sensing nodes |
| DO-41 package with JESD201 Class 2 whisker resistance | Supports automated insertion and reflow assembly while ensuring long-term mechanical and electrical stability in vibration-prone environments |
Applications
| Automotive Lighting Control | Industrial PLC Digital I/O Protection |
|---|---|
Use Scenario: Protecting LED driver ICs and MOSFET gate drivers from load-dump transients in 24 V vehicle lighting systems. IC Role / Device Role: Unidirectional TVS placed between 24 V supply rail and ground, clamping positive surges exceeding 256 V. Use Value: Limits peak voltage to 414 V during 400 W load dump events, preventing latch-up or permanent damage to 36 V-rated driver ICs. | Use Scenario: Safeguarding digital input channels of programmable logic controllers against EFT bursts and inductive kickback from solenoid valves. IC Role / Device Role: Series-connected TVS on 24 V input line, absorbing repetitive 5 kV EFT pulses per IEC 61000-4-4. Use Value: Maintains <1 μA leakage at nominal 24 V, avoiding false logic states while clamping transients to safe levels for optocoupler inputs. |
| DC Power Rail Surge Suppression | Telecom Power Interface Protection |
Use Scenario: Front-end protection for 250 V DC power supplies used in railway signaling equipment exposed to lightning-induced surges. IC Role / Device Role: Primary clamping device on main DC input, coordinated with upstream MOVs and downstream filtering. Use Value: Provides precise 256 V stand-off with 414 V clamping, enabling tighter design margins than generic 275 V MOVs and reducing follow-on current risk. | Use Scenario: Secondary-level surge protection on -48 V telecom power feeds entering remote radio units. IC Role / Device Role: Unidirectional TVS referenced to chassis ground, suppressing positive transients on negative-rail systems. Use Value: Operates reliably at –55 °C to +175 °C, supporting outdoor deployment in extreme climates without derating penalties. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ250A | DO-214AA package; 250 V VWM; 400 W PPK; 400 V VC @ 1 A; same 1 mA IT test condition | Surface-mount footprint requires PCB redesign; higher thermal resistance (RθJA ≈ 140 °C/W) limits high-ambient use | Select when space-constrained SMT layout is mandatory and thermal margin allows |
| P6KE250A | DO-15 package; 250 V VWM; 600 W PPK; 410 V VC @ 1.2 A; 10/1000 μs rating | Higher peak power but larger DO-15 body; lower surge current rating per watt due to different construction | Choose for legacy through-hole designs needing higher single-pulse energy absorption |
Compared with SMBJ250A and P6KE250A, the BZW04-256 offers identical clamping performance in a smaller DO-41 package with superior thermal coupling (RθJL = 60 °C/W), making it preferred for high-reliability automotive and industrial applications where lead-mounted thermal management is critical.
Availability
BZW04-256 is available at Aetrix Electronics and suitable for automotive lighting control, industrial PLC I/O protection, and DC power rail surge suppression requiring stable component supply across multi-year production cycles.
Supply support for BZW04-256 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
Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, specializing in power management, protection, and signal conditioning devices.
The BZW04 series is part of TSC's automotive-qualified TVS portfolio, engineered specifically for robust transient immunity in harsh-environment applications including vehicle electrification, industrial automation, and infrastructure power systems.
FAQ
What is the polarity configuration of the BZW04-256?
The BZW04-256 is a unidirectional TVS diode with cathode band marking. It functions as a reverse-biased avalanche clamp, conducting only when the cathode is at a higher potential than the anode - essential for protecting positive DC rails. This differs from bidirectional variants like BZW04-256B, which suppress both polarities. Correct orientation is mandatory for BZW04-256 to perform its specified clamping function.
Does the BZW04-256 meet AEC-Q101 qualification?
The base BZW04-256 is not automatically AEC-Q101 qualified; qualification applies only to versions marked with suffix "H" (e.g., BZW04-256H). The standard BZW04-256 meets all electrical and mechanical specifications in the datasheet but lacks the extended stress-test validation required for automotive under-hood use. For AEC-Q101 compliance, specify BZW04-256H when ordering.
What is the maximum clamping voltage for the BZW04-256 at its rated peak pulse current?
The BZW04-256 has a maximum clamping voltage (VC) of 414 V at 1 A peak impulse current (IPP), measured under the 10/1000 μs waveform per ANSI/IEEE C62.35. This value is guaranteed across the full operating temperature range and defines the upper voltage limit imposed on protected circuits during surge events - critical for ensuring downstream ICs remain within their absolute maximum ratings.
How does the BZW04-256 compare to the P6KE250A in terms of thermal performance?
The BZW04-256 exhibits superior thermal performance versus the P6KE250A: its junction-to-lead thermal resistance (RθJL) is 60 °C/W compared to ~80 °C/W for the P6KE250A in DO-15. This enables more efficient heat transfer through leads in high-temperature ambient conditions, supporting reliable operation up to +175 °C junction temperature without additional heatsinking - a key advantage in enclosed automotive and industrial enclosures.
Can the BZW04-256 be used in bidirectional surge protection applications?
No - the BZW04-256 is strictly unidirectional and must be used with correct polarity orientation. For bidirectional protection, the designated variant is BZW04-256B, which features symmetrical breakdown characteristics and no polarity marking. Using BZW04-256 in place of BZW04-256B will result in failure to clamp negative transients and potential damage to protected circuitry during reverse-polarity surges.
BZW04-256 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-204AL, DO-41, Axial
- Series:
- BZW04
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 256V
- Voltage - Breakdown (Min):
- 285V
- Voltage - Clamping (Max) @ Ipp:
- 414V
- Current - Peak Pulse (10/1000µs):
- 1A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AL (DO-41)
BZW04-256 FAQ
1.How can I place an order for BZW04-256 through Aetrix?
Please submit a Request for Quotation (RFQ) for BZW04-256 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 BZW04-256 reliable?
The price and inventory of BZW04-256 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZW04-256 is usually 5 days.
3.What payment methods are accepted for BZW04-256?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZW04-256 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZW04-256?
BZW04-256 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZW04-256 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 BZW04-256?
For technical support, including BZW04-256 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZW04-256 requirements.
6.How does Aetrix verify that BZW04-256 is sourced from the original manufacturer or authorized distributors?
All BZW04-256 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 BZW04-256 meets industry standards.
7.What is the process for return or replacement of BZW04-256?
All BZW04-256 units undergo pre-shipment inspection (PSI). If there is an issue with BZW04-256, 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 BZW04-256 part is unused and in its original packaging.
Return procedure for BZW04-256:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZW04-256 Tags
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