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Taiwan Semiconductor Corporation BZW04-37B
- Part No.:
- BZW04-37B
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
BZW04-37B.pdf
- Description:
- TVS DIODE 36.8VWM 59.3VC DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:5,998
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Product details
Overview
BZW04-37B from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode in DO-15 package, designed for high-energy ESD and surge protection in power rails and signal lines. It features a standoff voltage (VRM) of 37 V, clamping voltage (VCL) of 60.3 V at 4.3 A (10/1000 µs), peak pulse power of 400 W, and operates up to 175 °C junction temperature - deployed in industrial power supplies and telecom interface circuits.
For engineers reviewing the BZW04-37B datasheet, BZW04-37B pinout, BZW04-37B application, or BZW04-37B equivalent, key selection criteria include clamping performance at 8/20 µs vs. 10/1000 µs waveforms, bidirectional conduction symmetry, thermal derating above 25 °C, and compliance with IEC 61000-4-2 (±30 kV contact/air) and IEC 61000-4-4 Level 4 (4 kV).
Technical Context
The BZW04-37B implements planar junction technology optimized for low leakage (<1 µA at VRM) and stable VBR (37 V min / 41.8 V max at 25 °C) across -55 °C to +175 °C. Its bidirectional structure enables symmetrical clamping in AC-coupled or floating lines without polarity constraints.
Dynamic resistance (RD) is 2.61 Ω at 10/1000 µs and 1.79 Ω at 8/20 µs, enabling predictable voltage overshoot under fast transients. Junction capacitance remains ≤11 pF at 1 MHz and VR = 0 V, supporting high-speed data line protection without signal integrity degradation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 37 V - maximum continuous reverse operating voltage before breakdown; defines minimum system rail margin for reliable blocking. |
| Breakdown Voltage (VBR) | 37–41.8 V at 1 mA - tight tolerance ensures consistent triggering across temperature and production lots. |
| Clamping Voltage (VCL) | 60.3 V at 4.3 A (10/1000 µs) - limits downstream voltage stress during surge events; critical for IC-level overvoltage immunity. |
| Peak Pulse Power (PPP) | 400 W (10/1000 µs) - sustains repetitive surges in industrial power inputs without thermal runaway. |
| Junction Temperature Range | -55 °C to +175 °C - supports operation in harsh environments including automotive under-hood and industrial motor drives. |
| ESD Robustness | ±30 kV (IEC 61000-4-2, contact & air) - exceeds Level 4, eliminating need for external ESD staging in front-end interfaces. |
Pinout & Package
DO-15 (JEDEC DO-204AC) axial-leaded package: 6.05–6.75 mm body length (A), 26–31 mm lead length (B), 2.95–3.53 mm body diameter (C), 0.71–0.88 mm lead diameter (D). Matte tin-plated leads, RoHS-compliant, MSL Level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (Lead 1) | Transient current entry (bidirectional) | Conducts during positive or negative transients relative to cathode; symmetric conduction enables AC line protection. |
| Cathode (Lead 2) | Transient current exit (bidirectional) | Completes low-impedance path to ground or return rail; marking band identifies this terminal on unidirectional variants; absent on BZW04-37B due to bidirectional symmetry. |
Key Features
| Feature | Design Value |
|---|---|
| High-Temperature Operation | Rated for continuous use at Tj = 175 °C - eliminates derating concerns in enclosed power converters or high-ambient industrial enclosures. |
| Low Dynamic Resistance | RD = 2.61 Ω (10/1000 µs) - minimizes clamping voltage rise under high-current surges, preserving protected circuit margins. |
| Ultra-Low Leakage | IRM ≤ 1 µA at VRM = 37 V - prevents standby power loss and avoids false triggering in high-impedance sensor or battery-backed circuits. |
| Fast ESD Response | Sub-nanosecond turn-on - clamps IEC 61000-4-2 ESD pulses before sensitive logic or analog inputs are damaged. |
Applications
| Industrial Power Supply Input Protection | Telecom Line Interface Protection |
|---|---|
Use Scenario: 24 V DC input rail of programmable logic controller (PLC) exposed to load dump and inductive switching transients. IC Role / Device Role / Timing Role: Primary TVS clamp placed directly across input terminals to shunt surge energy before it reaches upstream DC-DC converter. Use Value: 400 W 10/1000 µs rating absorbs repeated 100 V/1 A transients per IEC 61000-4-4; 175 °C rating maintains reliability in sealed control cabinets. | Use Scenario: RS-485 data line in outdoor base station equipment subjected to lightning-induced surges and ESD events. IC Role / Device Role / Timing Role: Bidirectional TVS placed between differential pair (A/B) and ground to suppress common-mode transients without distorting signal integrity. Use Value: 11 pF junction capacitance ensures <1% signal attenuation at 10 Mbps; ±30 kV ESD rating eliminates need for secondary protection stages. |
| Automotive Body Control Module (BCM) Power Rail | Smart Meter AC Mains Surge Protection |
Use Scenario: 12 V supply line feeding microcontroller and CAN transceiver in BCM, subject to ISO 7637-2 pulse 1/2a/5a. IC Role / Device Role / Timing Role: Secondary overvoltage clamp after fuse and LC filter, providing final-stage protection against residual transients. Use Value: Symmetrical bidirectional response handles both positive and negative transients in vehicle electrical systems; DO-15 mechanical robustness withstands vibration testing. | Use Scenario: 230 V AC input stage of smart electricity meter, requiring compliance with IEC 61000-4-5 (10/700 µs) and EN 61000-4-4. IC Role / Device Role / Timing Role: Pre-regulator TVS across bridge rectifier output to limit peak DC bus voltage during surge events. Use Value: 60.3 V clamping at 4.3 A ensures downstream SMPS controller remains below absolute maximum ratings; 175 °C rating supports sealed meter housing operation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ36CA | Bidirectional, 36 V VRM, 58.1 V VCL @ 6.9 A (10/1000 µs), SMB package (surface-mount) | Lower power rating (600 W peak), smaller footprint, higher thermal resistance than DO-15 | Select when board space is constrained and surge duty cycle is light; requires PCB copper area optimization for thermal management. |
| P6KE36CA | Bidirectional, 36 V VRM, 58.1 V VCL @ 6.9 A (10/1000 µs), DO-15 package, 600 W peak pulse power | Higher PPP (600 W vs. 400 W), wider VBR tolerance (36–40 V), lower Tj max (175 °C same) | Prefer for higher-energy surge environments where 400 W may be marginal; verify layout thermal relief matches P6KE's higher power dissipation. |
Compared with SMBJ36CA and P6KE36CA, BZW04-37B offers tighter VBR tolerance (37–41.8 V), lower dynamic resistance (2.61 Ω), and superior high-temperature leakage stability - making it optimal for precision power rail clamping where long-term reliability under thermal stress is critical.
Availability
BZW04-37B is available at Aetrix Electronics and suitable for industrial power supplies, telecom interface protection, automotive body control modules, and smart meter AC mains surge protection requiring stable component supply and long-lifecycle support.
Supply support for BZW04-37B 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, specializing in power management, analog, MEMS, and microcontrollers for industrial, automotive, and consumer markets.
The BZW04 series belongs to ST's high-reliability TVS diode portfolio, engineered specifically for robust transient suppression in demanding power conversion and communication infrastructure applications where thermal stability and ESD immunity are non-negotiable.
FAQ
What is the maximum clamping voltage of BZW04-37B under an 8/20 µs surge?
The clamping voltage (VCL) is 77.0 V at 5.2 A for the 8/20 µs waveform, per Table 2 of DS0660 Rev 4. This value is measured at Tamb = 25 °C and reflects the device's ability to limit transient voltage during fast-rising surges typical of lightning-induced events.
Is BZW04-37B suitable for protecting 24 V DC industrial sensors?
Yes - its 37 V standoff voltage provides adequate margin above 24 V nominal rails, and its 60.3 V clamping voltage ensures protected ICs remain within their absolute maximum ratings. The 1 µA leakage at VRM prevents interference with high-impedance sensor outputs.
How does junction temperature affect breakdown voltage in BZW04-37B?
VBR increases with temperature at a coefficient αT = 10.4 × 10⁻⁴ /°C. At 125 °C, VBR rises by ~10.4% versus 25 °C - from 37–41.8 V to approximately 40.8–46.1 V - ensuring safe margin retention across full operating range.
Can BZW04-37B replace P6KE36CA in existing designs?
It can serve as a functional substitute in DO-15 socketed layouts, but with 400 W vs. 600 W peak power, designers must verify that worst-case surge energy falls within BZW04-37B's derated capability - especially at elevated ambient temperatures where PPP drops to 230 W at Tj = 175 °C.
BZW04-37B 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:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 36.8V
- Voltage - Breakdown (Min):
- 40.9V
- Voltage - Clamping (Max) @ Ipp:
- 59.3V
- Current - Peak Pulse (10/1000µs):
- 6.7A
- 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)
BZW04-37B FAQ
1.How can I place an order for BZW04-37B through Aetrix?
Please submit a Request for Quotation (RFQ) for BZW04-37B 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 BZW04-37B reliable?
The price and inventory of BZW04-37B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZW04-37B is usually 5 days.
3.What payment methods are accepted for BZW04-37B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZW04-37B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZW04-37B?
BZW04-37B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZW04-37B 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 BZW04-37B?
For technical support, including BZW04-37B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZW04-37B requirements.
6.How does Aetrix verify that BZW04-37B is sourced from the original manufacturer or authorized distributors?
All BZW04-37B 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 BZW04-37B meets industry standards.
7.What is the process for return or replacement of BZW04-37B?
All BZW04-37B units undergo pre-shipment inspection (PSI). If there is an issue with BZW04-37B, 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 BZW04-37B part is unused and in its original packaging.
Return procedure for BZW04-37B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZW04-37B Tags
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