My Inquiry
My Account
Diodes Incorporated SMF4L33AQ-7
- Part No.:
- SMF4L33AQ-7
- Manufacturer:
- Diodes Incorporated
- Category:
- TVS Diodes
- Package:
- DO-219AA
- Datasheet:
-
SMF4L33AQ-7.pdf
- Description:
- TRANSIENT VOLTAGE SUPPRESSOR PP
- Quantity:
- Payment:
- Shipping:
Inventory:2,729
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMF4L33AQ-7 from Diodes Incorporated is a unidirectional transient voltage suppressor (TVS) diode designed for automotive-grade overvoltage protection in low-voltage power rails and signal lines. It features a 33 V working peak reverse voltage (VRWM), 36.7–40.6 V breakdown voltage (VBR), 53.3 V maximum clamping voltage (VC) at 7.5 A, and 400 W peak pulse power (10/1000 µs). It is AEC-Q101 qualified and used in battery contact protection and ECU power input stages.
For engineers reviewing the SMF4L33AQ-7 datasheet, SMF4L33AQ-7 pinout, SMF4L33AQ-7 application, or SMF4L33AQ-7 equivalent, this part is selected for robust ESD immunity (±30 kV air/contact per IEC61000-4-2), fast sub-1 ns response, and DO-219AA surface-mount compatibility in space-constrained automotive modules.
Technical Context
The SMF4L33AQ-7 operates as a unidirectional avalanche diode with cathode-band polarity marking, optimized for clamping transients on DC power paths where reverse polarity is not expected. Its junction capacitance is unspecified but typical for 33 V TVS devices in DO-219AA, supporting high-speed surge suppression without signal distortion in 12 V/24 V systems.
It delivers 400 W peak pulse power under the standardized 10/1000 µs waveform, with thermal resistance RθJA = 96 °C/W on FR-4 PCB and RθJC = 18 °C/W to case. The device sustains 40 A non-repetitive forward surge current (8.3 ms half-sine) and exhibits <0.5 µA reverse leakage at VRWM.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 33 V - Maximum continuous reverse operating voltage before clamping begins; sets safe margin above nominal 24 V automotive rail. |
| VBR (min/max) | 36.7 V / 40.6 V - Breakdown occurs within this range at 1 mA test current; ensures predictable turn-on during overvoltage events. |
| VC @ 7.5 A | 53.3 V - Clamped voltage at rated peak surge current; limits downstream IC stress to safe levels during ISO 7637-2 pulses. |
| PPK | 400 W - Peak pulse power handling (10/1000 µs); supports high-energy load dump and inductive switching transients. |
| IR @ VRWM | <0.5 µA - Ultra-low leakage preserves battery life in always-on vehicle modules such as telematics and body control units. |
| Response Time | <1.0 ns - Enables effective suppression of ESD and fast-rising transients before sensitive logic or analog circuitry is damaged. |
| AEC-Q101 | Qualified - Meets automotive reliability requirements for temperature cycling, HTRB, and ESD robustness in under-hood applications. |
Pinout & Package
Package: DO-219AA - ultra-thin, surface-mount plastic package (1.90 mm × 2.80 mm × 0.60 mm), halogen-free, RoHS-compliant, moisture sensitivity level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Input/Line side (cathode-banded end is cathode) | Connected to protected line (e.g., battery feed); current flows anode-to-cathode during clamping. |
| Cathode | Ground/reference side | Connected to system ground or low-impedance return path; defines unidirectional conduction direction. |
Key Features
| Feature | Design Value |
|---|---|
| IEC61000-4-2 ESD Protection | ±30 kV air discharge, ±30 kV contact discharge - exceeds automotive infotainment and sensor interface immunity requirements. |
| Clamping Ratio (VC/VBR) | ~1.36 - Low ratio ensures minimal overvoltage overshoot during surge events, protecting 3.3 V/5 V logic supplies downstream. |
| Thermal Performance | RθJC = 18 °C/W - Enables efficient heat transfer to PCB copper pour, critical for sustained operation in engine bay environments. |
| Lead-Free & Green Compliance | RoHS 3 compliant, <900 ppm Br+Cl, <1000 ppm Sb - satisfies global automotive OEM chemical content mandates. |
| Automotive Change Control | PPAP-capable, manufactured in IATF 16949-certified facilities - supports traceability and process control for Tier 1 production programs. |
Applications
| Battery Contact Protection | Body Control Module (BCM) Power Input |
|---|---|
|
Use Scenario: Protecting exposed battery terminals and jump-start interfaces against ESD, load dump, and reverse battery connection. IC Role / Device Role / Timing Role: Unidirectional TVS diode placed between battery feed and main fuse/distribution point. Use Value: Limits clamped voltage to 53.3 V during 7.5 A surges, preventing damage to upstream fuses and downstream DC-DC converters. |
Use Scenario: Safeguarding 12 V input to BCM microcontrollers and CAN transceivers from alternator-induced transients. IC Role / Device Role / Timing Role: Primary front-end clamping device on main power rail, preceding bulk capacitance and LDO regulators. Use Value: Sub-1 ns response ensures suppression before 100 ns–1 µs ISO 7637-2 pulse edges reach sensitive logic, reducing reset failures. |
| Telematics Unit (TCU) Power Supply | ADAS Camera Module Interface |
|
Use Scenario: Securing always-on 12 V supply to LTE/GNSS modules subject to long-term battery drain and ignition cycling. IC Role / Device Role / Timing Role: Standby-mode TVS on VBAT rail, co-located with reverse-polarity protection MOSFET. Use Value: 0.5 µA max leakage minimizes quiescent current draw, extending parked vehicle battery life beyond 60 days. |
Use Scenario: Protecting FAKRA or coaxial video input lines from ESD during service or environmental exposure. IC Role / Device Role / Timing Role: Secondary-level TVS on camera power and shield lines, after primary board-level filtering. Use Value: 400 W pulse rating handles multiple ESD strikes without degradation, maintaining image integrity across 100,000+ cycles. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ33A | DO-214AC package; higher RθJA (110 °C/W); 33 V VRWM, 53.3 V VC @ 7.5 A; same 400 W PPK. | Larger footprint (4.3 mm × 2.6 mm vs. 1.9 mm × 2.8 mm); less suitable for dense ADAS camera PCBs. | Select when legacy layout reuse is required or thermal mass allows larger package. |
| TPSMD33A | DO-214AB package; 33 V VRWM, 53.3 V VC @ 7.5 A; 400 W PPK; slightly slower response (~1.5 ns). | Higher profile (2.3 mm height vs. 0.6 mm); incompatible with ultra-low-profile automotive modules. | Choose only if existing SMA footprint compatibility is mandatory and height constraints are relaxed. |
Compared with SMAJ33A and TPSMD33A, the SMF4L33AQ-7 offers superior board-space efficiency (DO-219AA), lower thermal resistance, and tighter height control-critical for next-generation compact automotive ECUs where PCB real estate and under-hood thermal management are constrained.
Availability
SMF4L33AQ-7 is available at Aetrix Electronics and suitable for automotive battery protection, body control module design, and telematics power conditioning requiring stable component supply across multi-year production cycles.
Supply support for SMF4L33AQ-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 components for automotive, industrial, and consumer markets.
The SMF4L series belongs to Diodes' AEC-Q101-qualified TVS portfolio, engineered specifically for robust transient suppression in harsh automotive environments including engine control, lighting, and ADAS subsystems.
FAQ
What is the polarity configuration of SMF4L33AQ-7?
The SMF4L33AQ-7 is a unidirectional TVS diode with cathode band marking. Anode connects to the protected line (e.g., battery +), cathode to ground. It conducts only during positive transients relative to ground and blocks reverse voltage up to –33 V, making it unsuitable for bidirectional AC or floating signal lines.
Does SMF4L33AQ-7 meet ISO 7637-2 Pulse 5a requirements?
Yes - with a 53.3 V clamping voltage at 7.5 A and 400 W peak power rating, the SMF4L33AQ-7 can suppress ISO 7637-2 Pulse 5a (load dump) transients up to 120 V/10 Ω source impedance when used with appropriate series impedance (e.g., 100 mΩ fuse or ferrite bead) to limit peak current into the device.
Can SMF4L33AQ-7 be used in parallel for higher surge current handling?
No - due to manufacturing tolerances in VBR (36.7–40.6 V), paralleling multiple SMF4L33AQ-7 devices causes current imbalance and premature failure of the lowest-VBR unit. For >7.5 A surge capability, select a higher-rated single device such as SMF4L36AQ-7 (VC = 58.1 V @ 6.9 A) or use a TVS array with matched characteristics.
Is the DO-219AA package compatible with standard reflow profiles?
Yes - the DO-219AA package is rated for moisture sensitivity level 1 and supports IPC/JEDEC J-STD-020D-compliant lead-free reflow profiles (peak 260 °C, 60 s above 217 °C). Its matte tin finish ensures reliable solder wetting on OSP- or ENIG-finished PCBs without voiding or tombstoning.
SMF4L33AQ-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):
- 33V
- Voltage - Breakdown (Min):
- 36.7V
- Voltage - Clamping (Max) @ Ipp:
- 53.3V
- Current - Peak Pulse (10/1000µs):
- 7.5A
- 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
SMF4L33AQ-7 FAQ
1.How can I place an order for SMF4L33AQ-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF4L33AQ-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 SMF4L33AQ-7 reliable?
The price and inventory of SMF4L33AQ-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMF4L33AQ-7 is usually 5 days.
3.What payment methods are accepted for SMF4L33AQ-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF4L33AQ-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF4L33AQ-7?
SMF4L33AQ-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF4L33AQ-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 SMF4L33AQ-7?
For technical support, including SMF4L33AQ-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF4L33AQ-7 requirements.
6.How does Aetrix verify that SMF4L33AQ-7 is sourced from the original manufacturer or authorized distributors?
All SMF4L33AQ-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 SMF4L33AQ-7 meets industry standards.
7.What is the process for return or replacement of SMF4L33AQ-7?
All SMF4L33AQ-7 units undergo pre-shipment inspection (PSI). If there is an issue with SMF4L33AQ-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 SMF4L33AQ-7 part is unused and in its original packaging.
Return procedure for SMF4L33AQ-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF4L33AQ-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…
