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onsemi MMBZ18VALT1
- Part No.:
- MMBZ18VALT1
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
MMBZ18VALT1.pdf
- Description:
- TVS DIODE 14.5VWM 25VC SOT23-3
- Quantity:
- Payment:
- Shipping:
Inventory:3,145
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Product details
Overview
MMBZ18VALT1 from onsemi is a dual common-anode Zener diode array in SOT-23 package, designed for transient overvoltage and ESD protection of two independent signal lines. It features a nominal Zener breakdown voltage of 18 V (17.1–18.9 V), 40 W peak pulse power at 1.0 ms, clamping voltage of 25 V at 1.6 A peak pulse current, and IEC 61000-4-2 Level 4 ±30 kV contact discharge rating. It is used in USB, HDMI, and RS-485 interface protection where board space is constrained.
For engineers reviewing the MMBZ18VALT1 datasheet, pinout, applications, or equivalent options, key selection criteria include bidirectional/unidirectional configuration flexibility, low clamping voltage under surge, dual-line protection per package, and AEC-Q101 qualification readiness for industrial and automotive edge nodes.
Technical Context
This device integrates two monolithic Zener junctions sharing a common anode (Pin 3), enabling either two independent unidirectional clamps (Pins 1–3 and 2–3) or one bidirectional clamp (Pins 1–2). Its thermal resistance is 417 °C/W on alumina substrate, supporting sustained operation up to +150 °C junction temperature.
The 40 W peak power rating applies under the non-repetitive 1.0 ms rectangular waveform per Figure 6, with derating above 25 °C ambient per Figure 7. Leakage current is limited to ≤50 nA at 14.5 V working reverse voltage, ensuring minimal standby loading on protected lines.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VBR) | 17.1–18.9 V @ 1.0 mA test current - defines precise clamping threshold for 18 V nominal rail protection |
| Peak Pulse Power (Ppk) | 40 W @ 1.0 ms - sustains high-energy ESD transients without failure per IEC 61000-4-2 |
| Clamping Voltage (VC) | 25 V @ 1.6 A peak pulse current - limits voltage overshoot during surge events |
| Working Reverse Voltage (VRWM) | 14.5 V - maximum continuous reverse bias before significant leakage onset |
| ESD Rating | ±30 kV contact discharge (IEC 61000-4-2 Level 4) - meets industrial-grade ESD immunity requirements |
| Leakage Current (IR) | ≤50 nA @ 14.5 V - avoids signal integrity degradation on high-impedance data lines |
| Package | SOT-23 (Case 318, Style 12) - surface-mount, 2.9 × 1.3 × 1.0 mm footprint for high-density PCB layouts |
Pinout & Package
SOT-23 package (Case 318, Style 12) with gull-wing leads, Pb-free and RoHS compliant. Designed for automated placement and reflow soldering at 260 °C for 10 seconds.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | Cathode 1 | First Zener junction cathode - connects to Line 1 for unidirectional clamping to common anode |
| Pin 2 | Cathode 2 | Second Zener junction cathode - connects to Line 2 for independent or bidirectional clamping |
| Pin 3 | Anode (Common) | Shared anode node - ties both Zeners to ground or reference rail; enables dual-line protection in single footprint |
Key Features
| Feature | Design Value |
|---|---|
| Dual common-anode topology | Protects two signal lines (e.g., differential pair or separate I/Os) with one SOT-23 device - reduces BOM count and layout area by 50% vs. discrete diodes |
| IEC 61000-4-2 Level 4 compliance | ±30 kV contact discharge rating - exceeds industrial immunity requirements without external circuitry |
| Low clamping voltage | 25 V at 1.6 A peak pulse - ensures downstream ICs (e.g., 3.3 V or 5 V logic) remain within safe operating voltage during surge |
| Thermal robustness | −55 °C to +150 °C junction temperature range - supports operation in automotive under-hood and industrial control environments |
| Pb-free and RoHS compliant | Meets global environmental regulations and enables lead-free reflow assembly without reliability compromise |
Applications
| USB 2.0 Data Line Protection | HDMI Hot-Plug Detection Line |
|---|---|
|
Use Scenario: Protecting D+ and D− lines against ESD events during cable insertion/removal in portable docking stations. IC Role / Device Role / Timing Role: Dual unidirectional transient voltage suppressor - each cathode (Pins 1 & 2) guards one data line referenced to common anode (Pin 3) tied to system ground. Use Value: Prevents latch-up or damage to USB transceivers while maintaining signal integrity due to low capacitance (<30 pF) and sub-25 V clamping. |
Use Scenario: Safeguarding the HDMI HPD (Hot-Plug Detect) signal line against electrostatic discharge during display connection. IC Role / Device Role / Timing Role: Unidirectional Zener clamp - Pin 1–3 protects HPD (5 V tolerant) against positive transients; Pin 2 remains unused or grounded for redundancy. Use Value: Ensures reliable plug-detect functionality without false triggers or port disablement after repeated ESD exposure. |
| RS-485 Transceiver Bus Lines | Industrial Sensor Interface Inputs |
|
Use Scenario: Protecting A and B differential bus lines of RS-485 transceivers in factory automation networks exposed to cable-induced surges. IC Role / Device Role / Timing Role: Bidirectional clamp - Pins 1 and 2 form a symmetric Zener pair across the differential pair, with common anode (Pin 3) connected to local ground. Use Value: Limits differential and common-mode overvoltages simultaneously, preserving signal fidelity and preventing transceiver damage during lightning-induced surges. |
Use Scenario: Shielding analog inputs of PLC analog input modules from field-wiring ESD and inductive kickback in harsh manufacturing environments. IC Role / Device Role / Timing Role: Dual unidirectional protector - Pin 1–3 clamps sensor VOUT line; Pin 2–3 clamps reference or enable line, both referenced to module ground (Pin 3). Use Value: Maintains measurement accuracy by limiting transient-induced offset shifts and avoids system resets caused by input-stage overstress. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-Zener ESD protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MMBZ18VALT1G | Same electrical specs and SOT-23 package; "G" suffix denotes Pb-free marking compliance per onsemi standard | No functional difference - identical performance and footprint; differs only in packaging marking convention | Select MMBZ18VALT1G when explicit Pb-free traceability documentation is required per procurement policy |
| SZMMBZ18VALT1G | AEC-Q101 qualified, automotive-grade variant with enhanced process controls and PPAP support | Required for automotive infotainment or ADAS sensor interfaces; not necessary for commercial/industrial use | Choose SZMMBZ18VALT1G only when automotive qualification and supply chain traceability are mandated |
Compared with MMBZ18VALT1, MMBZ18VALT1G offers identical protection performance with standardized Pb-free marking, while SZMMBZ18VALT1G adds automotive qualification overhead - select based on end-equipment certification needs, not electrical performance.
Availability
MMBZ18VALT1 is available at Aetrix Electronics and suitable for USB interface protection, industrial sensor front-ends, and RS-485 communication systems requiring stable component supply and long-term manufacturability.
Supply support for MMBZ18VALT1 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
onsemi (Semiconductor Components Industries, LLC) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.
The MMBZxxxALT1G series targets compact, high-reliability transient protection for space-constrained electronics - engineered specifically for dual-line ESD suppression in consumer, computing, and industrial interfaces.
FAQ
What is the Zener breakdown voltage tolerance for MMBZ18VALT1?
The MMBZ18VALT1 has a nominal Zener breakdown voltage of 18 V with a guaranteed range of 17.1 V to 18.9 V at 1.0 mA test current, corresponding to ±5% tolerance. This tight specification ensures consistent clamping behavior across production lots and temperature ranges from −55 °C to +150 °C, critical for protecting 18 V-rated circuits or establishing precise voltage references in protection networks.
Can MMBZ18VALT1 be used in bidirectional ESD protection mode?
Yes, MMBZ18VALT1 supports bidirectional operation by connecting the two cathodes (Pins 1 and 2) across a differential signal pair and tying the common anode (Pin 3) to ground. In this configuration, either cathode conducts during positive or negative transients, achieving symmetrical clamping - verified in the datasheet's typical characteristics and application diagrams for RS-485 and HDMI use cases.
What is the maximum clamping voltage of MMBZ18VALT1 under surge conditions?
The MMBZ18VALT1 clamps to a maximum of 25 V at 1.6 A peak pulse current (IPP), measured using the 1.0 ms rectangular waveform per Figure 6. This value is confirmed in the Electrical Characteristics table for the 40 W variant and represents the upper limit of voltage seen by protected circuitry during worst-case ESD or surge events - essential for verifying compatibility with downstream IC absolute maximum ratings.
Is MMBZ18VALT1 suitable for automotive applications?
The base MMBZ18VALT1 is not AEC-Q101 qualified; however, its automotive-grade counterpart SZMMBZ18VALT1G is fully qualified and PPAP-capable. For non-safety-critical automotive subsystems (e.g., infotainment USB ports), MMBZ18VALT1 may be used at design risk, but certified applications require the SZ-prefixed version to meet automotive quality and traceability standards.
How does the thermal performance of MMBZ18VALT1 compare between FR-5 and alumina substrates?
On FR-5 board, MMBZ18VALT1 has a thermal resistance of 556 °C/W and 225 mW steady-state power dissipation at 25 °C; on alumina substrate, it improves to 417 °C/W and 300 mW. This 25% lower RJA on alumina allows higher continuous power handling or extended operation in elevated ambient temperatures - relevant for sealed industrial enclosures or automotive under-dash environments.
MMBZ18VALT1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 2
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 14.5V
- Voltage - Breakdown (Min):
- 17.1V
- Voltage - Clamping (Max) @ Ipp:
- 25V
- Current - Peak Pulse (10/1000µs):
- 1.6A
- Power - Peak Pulse:
- 40W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-3 (TO-236)
MMBZ18VALT1 FAQ
1.How can I place an order for MMBZ18VALT1 through Aetrix?
Please submit a Request for Quotation (RFQ) for MMBZ18VALT1 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 MMBZ18VALT1 reliable?
The price and inventory of MMBZ18VALT1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMBZ18VALT1 is usually 5 days.
3.What payment methods are accepted for MMBZ18VALT1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMBZ18VALT1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMBZ18VALT1?
MMBZ18VALT1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMBZ18VALT1 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 MMBZ18VALT1?
For technical support, including MMBZ18VALT1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMBZ18VALT1 requirements.
6.How does Aetrix verify that MMBZ18VALT1 is sourced from the original manufacturer or authorized distributors?
All MMBZ18VALT1 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 MMBZ18VALT1 meets industry standards.
7.What is the process for return or replacement of MMBZ18VALT1?
All MMBZ18VALT1 units undergo pre-shipment inspection (PSI). If there is an issue with MMBZ18VALT1, 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 MMBZ18VALT1 part is unused and in its original packaging.
Return procedure for MMBZ18VALT1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMBZ18VALT1 Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
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
-
D5V0L1B2WS-7
Diodes Incorporated
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