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STMicroelectronics STPS3L40SY
- Part No.:
- STPS3L40SY
- Manufacturer:
- STMicroelectronics
- Category:
- Single Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
STPS3L40SY.pdf
- Description:
- DIODE SCHOTTKY 40V 3A SMC
- Quantity:
- Payment:
- Shipping:
Inventory:4,554
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Product details
Overview
STPS3L40SY from STMicroelectronics is an AEC-Q101-qualified automotive Schottky rectifier in SMC package, rated for 3 A average forward current and 40 V repetitive peak reverse voltage, with max forward voltage drop of 0.44 V at 125 °C and 3 A. It delivers low conduction loss (P = 0.30 × IF(AV) + 0.047 × IF²(RMS)) and supports DC/DC chargers in engine control units and body electronics.
For engineers reviewing the STPS3L40SY datasheet, STPS3L40SY pinout, STPS3L40SY application, or STPS3L40SY equivalent, key selection criteria include its 18 °C/W junction-to-lead thermal resistance, avalanche capability up to 1300 W (tp = 1 µs), ECOPACK®2 compliance, and operation across –40 to +150 °C junction temperature range.
Technical Context
This Schottky rectifier uses a planar silicon structure optimized for minimal switching losses and high-frequency operation in automotive DC/DC converters. Its low VF (0.40–0.44 V @ 125 °C, 3 A) and negligible reverse recovery charge enable efficient power conversion above 100 kHz.
The device features specified unclamped inductive switching (UIS) capability with 1300 W peak avalanche power at Tj = 25 °C and tp = 1 µs, and is qualified per AEC-Q101 for use in harsh automotive environments without derating below 150 °C maximum junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRRM | 40 V - Maximum reverse blocking voltage before breakdown; defines safe operating range in 12 V/24 V automotive systems. |
| IF(AV) | 3 A - Continuous forward current at TL = 120 °C with 50% duty cycle; supports compact heatsink designs in space-constrained modules. |
| VF(max) | 0.44 V - Max forward voltage at 3 A and 125 °C; reduces conduction loss to ≤1.32 W under worst-case thermal conditions. |
| Rth(j-l) | 18 °C/W - Junction-to-lead thermal resistance; enables direct thermal coupling to PCB copper or metal-core substrates for passive cooling. |
| IFSM | 75 A - Non-repetitive surge current for 10 ms sine half-cycle; withstands load dump transients in automotive power rails. |
| Tj(max) | +150 °C - Maximum junction temperature; allows full-rated operation in under-hood environments without active cooling. |
| IR(max) | 40 mA - Max reverse leakage at 125 °C and VR = VRRM; ensures stable blocking performance during hot standby modes. |
Pinout & Package
STPS3L40SY is housed in an SMC (DO-214AB) surface-mount package with two terminals: cathode and anode. The package features gull-wing leads, epoxy body compliant with UL94 V0, and lead-free construction meeting ECOPACK®2 environmental requirements.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward current entry point | Connected to input rail (e.g., battery or boost stage output); must be routed with low-inductance trace for high di/dt stability. |
| Cathode | Forward current exit point | Connected to output node (e.g., buck converter input or filter capacitor); serves as reference for thermal pad attachment on PCB. |
Key Features
| Feature | Design Value |
|---|---|
| Negligible switching losses | No reverse recovery charge (Qrr ≈ 0), eliminating turn-off loss and EMI in >100 kHz DC/DC topologies. |
| Low thermal resistance | Rth(j-l) = 18 °C/W enables ≥2.5 W dissipation with <45 °C rise over lead temperature-no external heatsink required. |
| Avalanche capability | Rated 1300 W UIS at 1 µs pulse; protects against inductive kickback in solenoid drivers and motor control feedback paths. |
| AEC-Q101 qualification | Validated for automotive under-hood use including temperature cycling, humidity bias, and mechanical shock per stress test standard. |
| ECOPACK®2 compliance | Lead-free, halogen-free, RoHS-compliant packaging with UL94 V0 flammability rating for safety-critical modules. |
Applications
| Engine Control Unit (ECU) Power Supply | Automotive Infotainment DC/DC Converter |
|---|---|
Use Scenario: Regulating 12 V battery input to 5 V/3.3 V rails for microcontroller and CAN transceiver power domains. IC Role / Device Role / Timing Role: Output rectifier in synchronous buck converter secondary side, handling 2–3 A continuous load with minimal voltage drop. Use Value: 0.44 V VF at 125 °C reduces power loss by ≥18% vs. comparable 0.52 V diodes, lowering thermal stress on adjacent ASICs. | Use Scenario: Isolating auxiliary 12 V supply from main vehicle bus in head unit power management system. IC Role / Device Role / Timing Role: Freewheeling diode in flyback converter primary-side clamp circuit, absorbing leakage inductance energy. Use Value: 1300 W avalanche rating safely clamps 100–200 V spikes from transformer leakage without failure during cold-cranking events. |
| Body Control Module (BCM) Charger | ADAS Camera Power Interface |
Use Scenario: Charging backup supercapacitors from alternator output during engine stop-start cycles. IC Role / Device Role / Timing Role: Unidirectional isolation diode between alternator rectifier output and energy storage capacitor bank. Use Value: Low IR (≤40 mA @ 125 °C) prevents self-discharge of stored energy during extended parking periods (>72 h). | Use Scenario: Providing clean 5 V power to CMOS image sensor and ISP in rear-view camera module mounted near exhaust. IC Role / Device Role / Timing Role: Input protection and reverse-polarity blocking diode upstream of LDO regulator. Use Value: +150 °C Tj(max) and AEC-Q101 qualification ensure reliable operation at ambient temperatures up to +105 °C near hot components. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Schottky rectifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ON Semiconductor NSS3L40MX | Same SMC package, 3 A/40 V rating, but VF = 0.52 V (max) at 125 °C - 18% higher conduction loss. | Not AEC-Q101 qualified; limited to non-safety-critical consumer-grade modules. | Select only if cost sensitivity outweighs thermal margin and automotive qualification requirements. |
| Vishay VS-3EY04-M3 | SMC package, 3 A/40 V, VF = 0.45 V (max) at 125 °C; Rth(j-l) = 20 °C/W - 11% higher thermal resistance. | Qualified to AEC-Q101 but lacks specified avalanche rating; unsuitable for inductive clamp circuits. | Preferable for simple OR-ing or reverse polarity protection where UIS stress is absent. |
Compared with NSS3L40MX and VS-3EY04-M3, STPS3L40SY offers the lowest VF and highest avalanche robustness among SMC-packaged 40 V Schottkys, making it optimal for thermally constrained, high-reliability automotive DC/DC stages requiring both efficiency and transient resilience.
Availability
STPS3L40SY is available at Aetrix Electronics and suitable for engine control units, body control modules, and ADAS camera power interfaces requiring stable component supply across automotive production lifecycles.
Supply support for STPS3L40SY 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, designing and manufacturing analog, MCU, power, and sensor solutions for automotive, industrial, and consumer markets.
STPS3L40SY belongs to ST's automotive-qualified power diode product line, engineered specifically for high-efficiency, high-reliability rectification in under-hood DC/DC conversion and battery management subsystems.
FAQ
Is STPS3L40SY suitable for synchronous rectification?
No - STPS3L40SY is a passive Schottky diode, not a MOSFET-based synchronous rectifier. It lacks gate control and cannot be actively switched. It functions as a freewheeling or output rectifier in non-synchronous topologies like standard buck or flyback converters where simplicity and reliability outweigh marginal efficiency gains from synchronous operation.
What is the minimum recommended copper area for thermal relief on the SMC footprint?
Per Figure 10 in the datasheet, a 4.5 cm² copper surface under each lead reduces Rth(j-a) to ~75 °C/W. For continuous 3 A operation at 125 °C ambient, ≥10 cm² total copper (5 cm² per lead) is recommended to maintain Tj ≤ 150 °C without forced airflow, using FR4 board with 35 µm copper thickness.
Does STPS3L40SY require derating when used in sealed enclosures?
Yes - in sealed enclosures with no airflow, thermal resistance rises significantly. With Rth(j-a) ≈ 120 °C/W (vs. 75 °C/W with 4.5 cm² copper), power dissipation must be limited to ≤1.25 W to hold Tj ≤ 150 °C at 85 °C ambient. This corresponds to ~2.2 A average current at 125 °C junction temperature, requiring design margin verification.
Can STPS3L40SY replace a standard PN junction rectifier in existing automotive designs?
Yes - as a direct drop-in replacement for 40 V, 3 A PN rectifiers (e.g., 1N5404), STPS3L40SY reduces forward voltage by ~0.4 V, cutting conduction loss by >50% and eliminating reverse recovery noise. However, verify layout clearance: SMC footprint differs from DO-41/DO-15, and thermal pad routing must accommodate gull-wing leads.
STPS3L40SY Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- Q
- Package/Case:
- DO-214AB, SMC
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Technology:
- Schottky
- Voltage - DC Reverse (Vr) (Max):
- 40 V
- Current - Average Rectified (Io):
- 3A
- Voltage - Forward (Vf) (Max) @ If:
- 500 mV @ 3 A
- Speed:
- Fast Recovery =< 500ns, > 200mA (Io)
- Reverse Recovery Time (trr):
- -
- Current - Reverse Leakage @ Vr:
- 100 µA @ 40 V
- Capacitance @ Vr, F:
- -
- Grade:
- Automotive
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMC
- Operating Temperature - Junction:
- -40°C ~ 150°C
STPS3L40SY FAQ
1.How can I place an order for STPS3L40SY through Aetrix?
Please submit a Request for Quotation (RFQ) for STPS3L40SY 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 STPS3L40SY reliable?
The price and inventory of STPS3L40SY are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STPS3L40SY is usually 5 days.
3.What payment methods are accepted for STPS3L40SY?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STPS3L40SY transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for STPS3L40SY?
STPS3L40SY orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your STPS3L40SY 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 STPS3L40SY?
For technical support, including STPS3L40SY datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STPS3L40SY requirements.
6.How does Aetrix verify that STPS3L40SY is sourced from the original manufacturer or authorized distributors?
All STPS3L40SY 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 STPS3L40SY meets industry standards.
7.What is the process for return or replacement of STPS3L40SY?
All STPS3L40SY units undergo pre-shipment inspection (PSI). If there is an issue with STPS3L40SY, 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 STPS3L40SY part is unused and in its original packaging.
Return procedure for STPS3L40SY:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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