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STMicroelectronics BZW50-56B
- Part No.:
- BZW50-56B
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- R-6, Axial
- Datasheet:
-
BZW50-56B.pdf
- Description:
- TVS DIODE 56VWM 129VC R6
- Quantity:
- Payment:
- Shipping:
Inventory:409
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Product details
Overview
BZW50-56B from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode designed for high-energy surge protection in power and signal lines. It features a 56 V stand-off voltage, 62.2 V minimum breakdown voltage at 1 mA, 99.6 V maximum clamping voltage at 50 A (10/1000 µs), 5000 W peak pulse power rating, and operates up to 175 °C junction temperature - deployed in industrial AC/DC front-ends and telecom line interfaces.
For engineers reviewing the BZW50-56B datasheet, BZW50-56B pinout, BZW50-56B application, or BZW50-56B equivalent, key selection criteria include clamping voltage margin vs. protected IC VDD, bidirectional polarity handling for AC-coupled lines, thermal derating above 25 °C, and R6 package solderability per J-STD-020 reflow profile.
Technical Context
The BZW50-56B employs planar silicon junction technology optimized for low leakage (<5 µA at 56 V) and stable dynamic resistance (0.617 Ω at 10/1000 µs), enabling reliable clamping under repetitive surges. Its bidirectional architecture supports symmetrical overvoltage protection on balanced lines without polarity constraints.
It meets IEC 61000-4-2 level 4 (±30 kV contact/air discharge) and IEC 61000-4-4 level 4 (4 kV), with clamping performance validated across junction temperatures from –55 °C to +175 °C using αT = 10.4 × 10–4/°C voltage temperature coefficient.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Stand-off Voltage (VRM) | 56 V - Maximum continuous reverse operating voltage before significant leakage begins. |
| Breakdown Voltage (VBR) | 62.2 V min @ 1 mA - Confirmed turn-on threshold ensuring predictable clamping onset. |
| Clamping Voltage (VCL) | 99.6 V max @ 50 A, 10/1000 µs - Limits downstream voltage stress during surge events. |
| Peak Pulse Power (PPP) | 5000 W @ 10/1000 µs - Sustains high-energy transients typical of lightning-induced surges. |
| Leakage Current (IRM) | ≤5 µA @ VRM - Minimizes standby power loss and avoids false triggering in high-impedance circuits. |
| Junction Temperature Range | –55 °C to +175 °C - Enables deployment in under-hood automotive, industrial motor drives, and outdoor telecom enclosures. |
| Dynamic Resistance (RD) | 0.617 Ω - Determines voltage rise slope under surge current, critical for precise clamping accuracy. |
Pinout & Package
The BZW50-56B is housed in the axial-leaded R6 package (JEDEC DO-201AD), with two terminals: anode and cathode marked by a cathode band on unidirectional variants; bidirectional versions (denoted by "B") have no polarity marking and function identically in either orientation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry point during forward conduction (unidirectional mode) | Not used for clamping in bidirectional operation; symmetric terminal for AC surge shunting. |
| Cathode | Current exit point during forward conduction (unidirectional mode) | Not used for clamping in bidirectional operation; symmetric terminal for AC surge shunting. |
Key Features
| Feature | Design Value |
|---|---|
| High-temperature reliability | Rated for continuous operation up to +175 °C junction temperature with verified leakage stability per Figure 9. |
| IEC 61000-4-2 compliance | Withstands ±30 kV air and contact ESD pulses - exceeds Level 4 requirements for industrial equipment. |
| Low dynamic resistance | 0.617 Ω ensures minimal voltage overshoot during 50 A transient, preserving margin for 3.3 V/5 V logic rails. |
| Planar junction construction | Delivers consistent parameter distribution and low capacitance (<100 pF at 0 V, per Figure 8), suitable for high-speed data lines. |
| UL 497B certification | QVGQ2.E136224 listing confirms suitability for primary-side telecom and PoE surge protection circuits. |
Applications
| Industrial AC/DC Power Supplies | Telecom Line Interface Protection |
|---|---|
Use Scenario: Protecting rectifier outputs and PFC stage inputs against lightning-induced surges on 230 VAC mains feeds. IC Role / Device Role / Timing Role: Bidirectional TVS clamp placed across bulk capacitor input to divert 5 kA 8/20 µs transients before they reach controller ICs. Use Value: Clamps to ≤99.6 V during 50 A surge, preventing overvoltage damage to 600 V MOSFETs and UC384x controllers. | Use Scenario: Shielding Ethernet PHY transformers and RJ45 jacks from induced surges in outdoor DSL/Cable modem installations. IC Role / Device Role / Timing Role: Bidirectional TVS mounted differential-mode across transformer secondary windings to suppress common-mode transients. Use Value: Low 0.617 Ω RD maintains <100 V clamping even at 40 A, preserving PHY IC integrity per IEEE 802.3af. |
| Automotive Body Control Modules | Smart Meter Communication Interfaces |
Use Scenario: Safeguarding LIN bus transceivers and microcontroller GPIOs from load-dump and ISO 7637-2 pulse 5a/b events. IC Role / Device Role / Timing Role: TVS placed between LIN line and ground to clamp fast-rising transients while maintaining <1 µA leakage at 12 V battery rail. Use Value: 5 µA max leakage at 56 V stand-off ensures no impact on LIN bus biasing or sleep-mode current budgets. | Use Scenario: Protecting RS-485 transceivers and PLC couplers in AMI smart meters exposed to utility grid switching transients. IC Role / Device Role / Timing Role: Bidirectional TVS installed on differential RS-485 lines to absorb ±4 kV IEC 61000-4-4 bursts without latch-up. Use Value: 175 °C Tjmax rating allows direct mounting near meter PCB heat sources without derating. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ58CA | 600 W rating (10/1000 µs), 58 V VRM, DO-214AA package | Limited to lower-energy surges; unsuitable for >2 kA 8/20 µs events | Select when space-constrained PCB layout requires SMD mounting and surge energy stays below 2 kW. |
| 1.5KE62CA | 1500 W rating (10/1000 µs), 62 V VRM, DO-201AE package | Higher VCL (102 V @ 24.3 A); lower thermal robustness (Tjmax = 175 °C but lower PPP density) | Choose where legacy through-hole compatibility is required and peak surge current remains ≤25 A. |
Compared with SMBJ58CA and 1.5KE62CA, the BZW50-56B delivers 3.3× higher peak power handling and tighter clamping (99.6 V vs. ≥102 V), making it the only option rated for sustained 5 kA surge duty in industrial-grade power systems.
Availability
BZW50-56B is available at Aetrix Electronics and suitable for industrial AC/DC power supplies, telecom line interface protection, and automotive body control modules requiring stable component supply across extended temperature and surge stress conditions.
Supply support for BZW50-56B 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, delivering intelligent power, analog, MEMS, and microcontroller solutions for industrial, automotive, and consumer markets.
The BZW50 series belongs to ST's high-power TVS diode product line, engineered specifically for robust, high-temperature surge immunity in mission-critical infrastructure - emphasizing low leakage, stable clamping, and long-term reliability under thermal cycling.
FAQ
What is the difference between BZW50-56 and BZW50-56B?
The "B" suffix denotes bidirectional configuration: BZW50-56B provides symmetrical clamping for AC or differential signals, while BZW50-56 is unidirectional with a cathode band marking. Both share identical VRM (56 V), VBR (62.2 V), and VCL (99.6 V), but only the "B" version functions identically regardless of polarity placement on the PCB.
Can BZW50-56B be used in parallel for higher surge current handling?
No - paralleling TVS diodes without matched dynamic resistance causes current imbalance and premature failure. The BZW50-56B's 0.617 Ω RD is tightly controlled, but ST does not recommend parallel operation. For >50 A surge capability, select a single higher-rated device like BZW50-47B (60.1 A) or use staged protection with MOV + TVS.
Does BZW50-56B require a heatsink for 5000 W pulse dissipation?
No - the 5000 W rating applies to a single 10/1000 µs pulse at Tj = 25 °C. Thermal simulation (Figure 11) shows Zth(j-a) ≈ 40 °C/W for short pulses; sustained power dissipation is limited to 6.5 W on infinite heatsink. PCB copper area (Figure 12) improves thermal performance but no external heatsink is needed for transient-only operation.
Is BZW50-56B RoHS and REACH compliant?
Yes - the BZW50-56B carries ECOPACK2 certification (ST's highest environmental grade), meeting RoHS Directive 2011/65/EU, REACH SVHC thresholds, and halogen-free requirements. Lead finish is matte tin plating per JESD 22-B102 E3, and packaging complies with UL94 V0 flammability standard.
BZW50-56B Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- R-6, Axial
- Series:
- BZW50, TRANSIL™
- Packaging:
- Cut Tape (CT)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 56V
- Voltage - Breakdown (Min):
- 62.2V
- Voltage - Clamping (Max) @ Ipp:
- 129V
- Current - Peak Pulse (10/1000µs):
- 465A (8/20µs)
- Power - Peak Pulse:
- 5000W (5kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- 1700pF @ 1MHz
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- R-6
BZW50-56B FAQ
1.How can I place an order for BZW50-56B through Aetrix?
Please submit a Request for Quotation (RFQ) for BZW50-56B 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 BZW50-56B reliable?
The price and inventory of BZW50-56B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BZW50-56B is usually 5 days.
3.What payment methods are accepted for BZW50-56B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BZW50-56B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for BZW50-56B?
BZW50-56B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your BZW50-56B 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 BZW50-56B?
For technical support, including BZW50-56B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BZW50-56B requirements.
6.How does Aetrix verify that BZW50-56B is sourced from the original manufacturer or authorized distributors?
All BZW50-56B 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 BZW50-56B meets industry standards.
7.What is the process for return or replacement of BZW50-56B?
All BZW50-56B units undergo pre-shipment inspection (PSI). If there is an issue with BZW50-56B, 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 BZW50-56B part is unused and in its original packaging.
Return procedure for BZW50-56B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
BZW50-56B Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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ESD5Z3.3T1G
onsemi
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D5V0H1B2LP-7B
Diodes Incorporated
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D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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D5V0L1B2WS-7
Diodes Incorporated
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