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onsemi MMQA18VT1G
- Part No.:
- MMQA18VT1G
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- SC-74, SOT-457
- Datasheet:
-
MMQA18VT1G.pdf
- Description:
- TVS DIODE 14VWM 26VC SC74
- Quantity:
- Payment:
- Shipping:
Inventory:5,290
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Product details
Overview
MMQA18VT1G from onsemi is a quad monolithic common-anode ESD protection diode designed for transient overvoltage suppression on four independent signal lines in space-constrained PCBs. It features a nominal Zener voltage of 18 V, maximum clamping voltage of 26 V at 1 A peak pulse current, and ESD rating >16 kV per Human Body Model (HBM Class 3B). It is used in computer I/O interfaces, microprocessor bus protection, and medical equipment signal line safeguarding.
For engineers reviewing the MMQA18VT1G datasheet, pinout, applications, or equivalent options, this device serves as a compact, Pb-free SC-74 solution for unidirectional surge protection where board area efficiency, low leakage (<75 nA), and precise 18 V breakdown are critical selection criteria.
Technical Context
The MMQA18VT1G implements a quad-junction common-anode architecture in a single SC-74 package, enabling four independent unidirectional protection paths sharing one anode terminal (pins 2 and 5). Each cathode-anode pair operates with a tightly specified breakdown voltage range of 17.1–18.9 V at 1 mA test current.
It delivers 24 W peak power dissipation (1.0 ms waveform) and 150 W (8 × 20 µs waveform), with thermal resistance of 556 °C/W on FR-5 board. Clamping performance is validated at IRSM = 1 A, yielding VRSM = 26 V - a key parameter for ensuring downstream ICs remain within safe operating voltage during ESD events.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Breakdown Voltage (VZ) | 17.1–18.9 V @ 1 mA - defines minimum trigger threshold for transient clamping across all four channels |
| Clamping Voltage (VRSM) | 26 V @ 1 A peak pulse - ensures protected circuit nodes stay below 26 V during 8 × 20 µs surges |
| Peak Pulse Power | 150 W @ 8 × 20 µs - supports high-energy ESD/IEC 61000-4-2 level 4 compliance |
| Reverse Leakage (IR) | <75 nA @ 14 V - minimizes standby current draw and signal integrity impact on high-impedance lines |
| ESD Rating (HBM) | >16 kV - exceeds IEC 61000-4-2 Level 4 (±8 kV contact / ±15 kV air) requirements |
| Junction Temp Range | −55 to +150 °C - enables operation in industrial and automotive under-hood environments |
| Capacitance @ 0 V | 19 pF - low enough for USB 2.0, RS-232, and parallel bus applications without signal degradation |
Pinout & Package
MMQA18VT1G uses the SC-74 (Case 318F) surface-mount package - a 6-pin, lead-free, void-free thermoset plastic body optimized for automated assembly and high-density layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | Cathode (Channel A) | Independent ESD path for Line A; connects to protected signal trace |
| Pin 2 | Anode (Common) | Shared anode node for all four channels; ties to system ground or bias rail |
| Pin 3 | Cathode (Channel B) | Independent ESD path for Line B; electrically isolated from other cathodes |
| Pin 4 | Cathode (Channel C) | Independent ESD path for Line C; enables 4-line protection in 2.1 mm × 2.0 mm footprint |
| Pin 5 | Anode (Common) | Second anode connection point - redundant bonding for lower inductance and improved surge handling |
| Pin 6 | Cathode (Channel D) | Independent ESD path for Line D; completes quad-channel configuration |
Key Features
| Feature | Design Value |
|---|---|
| Quad common-anode topology | Four discrete unidirectional protection paths share two anode pins - reduces component count and layout area by 75% vs. discrete diodes |
| Low clamping voltage | 26 V max at 1 A pulse - ensures logic-level interfaces (e.g., 3.3 V/5 V I/O) remain within absolute maximum ratings during transients |
| HBM Class 3B ESD rating | >16 kV - provides robust handling during manual assembly and end-user operation without external shielding |
| SC-74 footprint compatibility | 2.1 mm × 2.0 mm × 1.0 mm - fits standard pick-and-place workflows and enables routing under connectors or tight pitch headers |
| Pb-free & RoHS compliant | Meets JEDEC J-STD-020 reflow profile up to 260 °C - supports lead-free manufacturing without reliability compromise |
Applications
| Computer Keyboard Interface | Microprocessor Bus Protection |
|---|---|
|
Use Scenario: Protecting matrix scan lines in industrial keyboards exposed to repeated operator ESD events. IC Role / Device Role / Timing Role: Unidirectional transient voltage suppressor placed between each row/column line and ground. Use Value: Prevents latch-up or damage to MCU GPIOs while maintaining <19 pF capacitance to avoid ghost key detection errors. |
Use Scenario: Safeguarding address/data/control buses connecting CPU, RAM, and peripherals in embedded controllers. IC Role / Device Role / Timing Role: Common-anode clamp on parallel bus lines (e.g., AD0–AD7), with shared ground return. Use Value: Simultaneous protection of four bus lines with single-component placement - eliminates four discrete diodes and saves >3 mm² PCB area. |
| Medical Sensor Interface | Industrial Printer I/O Port |
|
Use Scenario: Shielding analog sensor inputs (e.g., temperature, pressure) in portable diagnostic devices from hospital-grade ESD sources. IC Role / Device Role / Timing Role: Low-leakage (<75 nA) voltage clamp on signal lines entering precision ADC front-end. Use Value: Maintains signal integrity and offset accuracy while providing >16 kV HBM immunity - critical for FDA-cleared device certification. |
Use Scenario: Hardening RS-232/USB host ports on label printers subject to cable-discharge events in warehouse environments. IC Role / Device Role / Timing Role: Quad-channel protector on TX/RX, RTS/CTS, or VBUS/D+/D− lines before transceiver ICs. Use Value: Delivers 150 W surge capacity per channel - withstands repetitive 8 × 20 µs pulses without parametric shift or failure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar ESD protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ESDA6V1SC6 | Single-channel, 6.1 V breakdown, 30 pF capacitance - higher capacitance, lower voltage rating | Requires four separate placements; unsuitable for 18 V rail protection but better for 3.3 V logic | Select when protecting low-voltage digital I/O where tighter voltage tolerance and lower clamping are prioritized over board area |
| SZMMQA18VT1G | Identical electrical specs; AEC-Q101 qualified, PPAP-capable, with automotive-specific traceability and change control | Approved for automotive infotainment and ADAS sensor interfaces requiring qualification documentation | Select for automotive programs needing PPAP support and extended temperature validation - same footprint and pinout as MMQA18VT1G |
Compared with ESDA6V1SC6, MMQA18VT1G offers quad integration and 18 V clamping for higher-voltage systems; compared with SZMMQA18VT1G, it lacks automotive qualification but provides identical performance for industrial/commercial use at lower cost and lead time.
Availability
MMQA18VT1G is available at Aetrix Electronics and suitable for computer interface protection, microprocessor bus safeguarding, and medical sensor signal conditioning requiring stable component supply across production lifecycles.
Supply support for MMQA18VT1G 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 (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, and cloud infrastructure markets.
The MMQA series belongs to onsemi's ESD and transient voltage suppression product line, engineered specifically for high-density, multi-line I/O protection in computing, medical, and industrial electronics where space, reliability, and HBM robustness are critical.
FAQ
What is the exact breakdown voltage range for MMQA18VT1G?
The MMQA18VT1G has a guaranteed breakdown voltage (VZT) range of 17.1 V to 18.9 V at 1.0 mA test current, measured per the datasheet's Figure 5 and Table on page 2. This tight 5% tolerance ensures consistent clamping behavior across production lots and temperature extremes, making MMQA18VT1G suitable for designs requiring predictable overvoltage response without margin stacking.
Does MMQA18VT1G support bidirectional ESD protection?
No, MMQA18VT1G is strictly unidirectional - its common-anode architecture requires the anode (pins 2 and 5) to be tied to ground or a positive bias rail, with cathodes (pins 1, 3, 4, 6) connected to protected signal lines. For bidirectional protection, onsemi offers complementary devices like the NUP4105MR6T1G, which uses a common-cathode dual-diode configuration.
What is the maximum allowable reverse standoff voltage for MMQA18VT1G in continuous operation?
The maximum reverse standoff voltage (VR) for MMQA18VT1G is 14 V - this is the highest DC voltage that can be continuously applied without exceeding the specified 75 nA leakage current. Operating above 14 V risks excessive leakage and premature conduction, so MMQA18VT1G is intended for circuits where normal signal swing remains ≤14 V, such as 12 V bus lines with headroom.
Can MMQA18VT1G be used in automotive applications?
The standard MMQA18VT1G is not AEC-Q101 qualified. For automotive use, the SZMMQA18VT1G variant must be selected - it shares identical electrical parameters and SC-74 packaging but includes automotive-specific process controls, PPAP documentation, and extended reliability testing per AEC-Q101. Using MMQA18VT1G in automotive systems may violate OEM qualification requirements.
How does the dual-anode pin configuration (pins 2 and 5) improve performance?
The dual-anode design (pins 2 and 5) in MMQA18VT1G reduces parasitic inductance and improves current sharing during fast transients by providing two parallel low-inductance paths to ground. This lowers overall clamping impedance and enhances surge current handling - verified by onsemi's 150 W 8 × 20 µs pulse rating - making MMQA18VT1G more effective than single-anode equivalents in high-speed ESD events.
MMQA18VT1G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- SC-74, SOT-457
- Series:
- MMQA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 4
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 14V (Max)
- Voltage - Breakdown (Min):
- 17.1V
- Voltage - Clamping (Max) @ Ipp:
- 26V
- Current - Peak Pulse (10/1000µs):
- 923mA (8/20µs)
- Power - Peak Pulse:
- 150W
- 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:
- SC-74
MMQA18VT1G FAQ
1.How can I place an order for MMQA18VT1G through Aetrix?
Please submit a Request for Quotation (RFQ) for MMQA18VT1G 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 MMQA18VT1G reliable?
The price and inventory of MMQA18VT1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MMQA18VT1G is usually 5 days.
3.What payment methods are accepted for MMQA18VT1G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MMQA18VT1G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MMQA18VT1G?
MMQA18VT1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MMQA18VT1G 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 MMQA18VT1G?
For technical support, including MMQA18VT1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MMQA18VT1G requirements.
6.How does Aetrix verify that MMQA18VT1G is sourced from the original manufacturer or authorized distributors?
All MMQA18VT1G 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 MMQA18VT1G meets industry standards.
7.What is the process for return or replacement of MMQA18VT1G?
All MMQA18VT1G units undergo pre-shipment inspection (PSI). If there is an issue with MMQA18VT1G, 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 MMQA18VT1G part is unused and in its original packaging.
Return procedure for MMQA18VT1G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MMQA18VT1G Tags
-
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
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ESD5Z5.0T1G
onsemi
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DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
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DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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D5V0L1B2WS-7
Diodes Incorporated
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