My Inquiry
My Account
Diodes Incorporated SMF4L120AQ-7
- Part No.:
- SMF4L120AQ-7
- Manufacturer:
- Diodes Incorporated
- Category:
- TVS Diodes
- Package:
- DO-219AA
- Datasheet:
-
SMF4L120AQ-7.pdf
- Description:
- TRANSIENT VOLTAGE SUPPRESSOR PP
- Quantity:
- Payment:
- Shipping:
Inventory:6,059
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMF4L120AQ-7 from Diodes Incorporated is a unidirectional 400W surface-mount transient voltage suppressor (TVS) diode designed for automotive-grade overvoltage protection in power rails and signal lines. It features a 120V working peak reverse voltage (VRWM), 133–147V breakdown voltage (VBR), 193V maximum clamping voltage (VC) at 2A, and AEC-Q101 qualification for under-hood and battery-contact applications.
For engineers reviewing the SMF4L120AQ-7 datasheet, SMF4L120AQ-7 pinout, SMF4L120AQ-7 application, or SMF4L120AQ-7 equivalent, key selection criteria include clamping performance under 10/1000µs surge, IEC 61000-4-2 ±30kV ESD robustness, DO-219AA package thermal resistance (RθJA = 96°C/W), and unidirectional polarity marking for correct PCB orientation.
Technical Context
This TVS operates as a voltage-clamped shunt protector: when transient voltage exceeds VBR (133–147V), it avalanches to divert surge current away from downstream circuitry. Its fast response (<1.0ns from 0V to VBR) ensures protection before sensitive ICs experience overstress.
Designed for automotive environments, it supports 175°C junction temperature operation, complies with AEC-Q101 stress testing (including temperature cycling, HTRB, and ESD), and is manufactured in IATF 16949-certified facilities with PPAP capability and green halogen/antimony-free molding compound.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power | 400W (10/1000µs waveform); sustains 2A surge at 193V clamping without failure |
| Working Peak Reverse Voltage (VRWM) | 120V; maximum continuous DC or RMS voltage applied without significant leakage |
| Breakdown Voltage (VBR) | 133–147V @ 1mA; precise avalanche onset threshold for reliable triggering |
| Maximum Clamping Voltage (VC) | 193V @ 2A; limits voltage seen by protected load during worst-case transient |
| ESD Withstand | ±30kV air/contact per IEC 61000-4-2; eliminates need for external ESD diodes on exposed ports |
| Junction Temperature Range | −55°C to +175°C; enables placement near hot components like power converters or engine controllers |
| Thermal Resistance (RθJA) | 96°C/W on 1"×1" FR-4 board; defines safe power derating above +25°C ambient |
Pinout & Package
Package: DO-219AA - ultra-compact surface-mount plastic case (2.80mm × 1.90mm × 0.60mm), matte tin-plated copper alloy leadframe, cathode band marking for unidirectional polarity, moisture sensitivity level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Transient current sink path during clamping | Connected to protected line; carries full surge current into ground reference |
| Cathode | Reference node (typically tied to system ground or low-impedance return) | Provides stable voltage reference for avalanche conduction; marked with visible band |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive use including temperature cycling, high-temp reverse bias, and ESD stress |
| Green "Halogen & Antimony Free" | Meets <900ppm Br, <900ppm Cl, <1000ppm Sb; compliant with EU RoHS 3 and automotive sustainability mandates |
| Fast response time | <1.0ns from 0V to VBR; prevents overshoot before protection activates |
| Low leakage at VRWM | 2.0μA max @ 120V; avoids power drain in always-on battery circuits |
| DO-219AA footprint | Enables high-density layout on space-constrained modules (e.g., ADAS ECUs, body control units) |
Applications
| Automotive Power Rail Protection | Battery Contact Interface |
|---|---|
Use Scenario: 12V/24V vehicle power distribution network exposed to load dump and jump-start transients. IC Role / Device Role / Timing Role: Unidirectional shunt TVS placed between battery rail and DC-DC converter input. Use Value: Clamps 193V surges at 2A while maintaining 120V VRWM margin-prevents overvoltage damage to buck controller ICs without affecting normal operation. | Use Scenario: Exposed battery terminal connections subject to ESD and contact bounce during connection/disconnection. IC Role / Device Role / Timing Role: Primary ESD clamp at physical interface, upstream of fuse and main power switch. Use Value: Withstands ±30kV IEC 61000-4-2 contact discharge and clamps within 1ns-eliminates latch-up risk in battery management ICs. |
| Engine Control Unit (ECU) Input Protection | Infotainment System USB/USB-C Port |
Use Scenario: Sensor supply lines (e.g., MAP, TPS) routed through engine bay where wiring harnesses couple in ignition noise. IC Role / Device Role / Timing Role: Localized TVS on each analog sensor rail, adjacent to connector entry point. Use Value: 133–147V VBR ensures no false triggering during nominal 12V operation while suppressing >150V spikes from solenoid switching. | Use Scenario: USB data/power lines in center console exposed to user-hand ESD and cable-induced surges. IC Role / Device Role / Timing Role: Unidirectional TVS on VBUS line only; paired with bi-directional TVS on D+/D−. Use Value: 120V VRWM allows compatibility with 20V PD charging while clamping VBUS surges to ≤193V-protects USB-PD controller without interfering with negotiation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ120A | Same 120V VRWM, but SMA package (larger DO-214AC); 400W rating, RθJA = 110°C/W | Less suitable for ultra-dense automotive modules due to 4.5mm × 2.7mm footprint vs. DO-219AA's 2.8mm × 1.9mm | Select if legacy board space allows larger package and thermal budget permits higher junction rise |
| TPSMD120 | 120V VRWM, 400W, but SOD-123FL package; lower clamping (180V @ 2A) and higher leakage (5μA) | Better for cost-sensitive consumer electronics; not AEC-Q101 qualified or PPAP capable | Choose only for non-automotive designs where qualification and leakage tolerance permit |
Compared with SMAJ120A and TPSMD120, SMF4L120AQ-7 delivers superior board-area efficiency, automotive qualification, and tighter leakage control-making it the optimal choice for next-generation compact, safety-critical vehicle electronics requiring traceable sourcing and lifecycle continuity.
Availability
SMF4L120AQ-7 is available at Aetrix Electronics and suitable for automotive power management, battery contact interfaces, and engine control unit (ECU) input protection requiring stable component supply across extended product lifecycles.
Supply support for SMF4L120AQ-7 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability protection, power management, and signal integrity solutions for automotive, industrial, and computing markets.
The SMF4L series belongs to Diodes' AEC-Q101-qualified TVS portfolio, engineered specifically for robust transient suppression in harsh automotive environments-including under-hood, battery, and infotainment systems-where reliability, small size, and regulatory compliance are mandatory.
FAQ
What is the polarity configuration of SMF4L120AQ-7?
SMF4L120AQ-7 is a unidirectional TVS diode, indicated by a cathode band marking on the DO-219AA package. It conducts only when the anode is more negative than the cathode-ideal for protecting positive-rail circuits against negative-going transients and positive surges relative to ground.
Does SMF4L120AQ-7 meet automotive qualification standards?
Yes-SMF4L120AQ-7 is AEC-Q101 qualified, PPAP capable, and manufactured in IATF 16949 certified facilities. It passes all required stress tests including high-temperature reverse bias (HTRB), temperature cycling, and ESD per JESD22-A114, making it suitable for ASIL-B and functional-safety-related applications.
How does its clamping voltage compare to similar 120V TVS devices?
At 2A surge current, SMF4L120AQ-7 clamps to 193V maximum-tighter than SMAJ120A (200V) and comparable to industry-leading alternatives. This lower VC reduces stress on downstream components such as LDOs and microcontrollers, directly improving system-level surge survivability.
Can SMF4L120AQ-7 be used in bidirectional configurations?
No-SMF4L120AQ-7 is unidirectional only. For bidirectional protection (e.g., AC lines or differential signals), use the companion part SMF4L120CAQ-7, which has identical electrical specs but no cathode band and symmetrical breakdown in both polarities.
SMF4L120AQ-7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Package/Case:
- DO-219AA
- Series:
- SMF4L
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 120V
- Voltage - Breakdown (Min):
- 133V
- Voltage - Clamping (Max) @ Ipp:
- 193V
- Current - Peak Pulse (10/1000µs):
- 2A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-219AA
SMF4L120AQ-7 FAQ
1.How can I place an order for SMF4L120AQ-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF4L120AQ-7 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 SMF4L120AQ-7 reliable?
The price and inventory of SMF4L120AQ-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMF4L120AQ-7 is usually 5 days.
3.What payment methods are accepted for SMF4L120AQ-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF4L120AQ-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF4L120AQ-7?
SMF4L120AQ-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF4L120AQ-7 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 SMF4L120AQ-7?
For technical support, including SMF4L120AQ-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF4L120AQ-7 requirements.
6.How does Aetrix verify that SMF4L120AQ-7 is sourced from the original manufacturer or authorized distributors?
All SMF4L120AQ-7 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 SMF4L120AQ-7 meets industry standards.
7.What is the process for return or replacement of SMF4L120AQ-7?
All SMF4L120AQ-7 units undergo pre-shipment inspection (PSI). If there is an issue with SMF4L120AQ-7, 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 SMF4L120AQ-7 part is unused and in its original packaging.
Return procedure for SMF4L120AQ-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF4L120AQ-7 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
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
