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Diodes Incorporated SDM4A40EP3-7B
- Part No.:
- SDM4A40EP3-7B
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Diodes
- Package:
- 0603 (1608 Metric)
- Datasheet:
-
SDM4A40EP3-7B.pdf
- Description:
- DIODE SCHOTT 40V 4A X3-TSN1608-2
- Quantity:
- Payment:
- Shipping:
Inventory:2,396
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Product details
Overview
SDM4A40EP3-7B from Diodes Incorporated is a 40 V, 4 A surface-mount Schottky barrier rectifier in X3-TSN1608-2 package, featuring 0.61 V max forward voltage at 4 A, 150 µA max reverse leakage at 40 V, and 1.28 mm² board footprint. It serves as a low-loss blocking or reverse protection diode in portable DC/DC converters and battery-powered systems.
For engineers reviewing the SDM4A40EP3-7B datasheet, SDM4A40EP3-7B pinout, SDM4A40EP3-7B application, or SDM4A40EP3-7B equivalent, key selection criteria include forward voltage drop at rated current, high-temperature reverse leakage behavior, thermal resistance to ambient under defined PCB layout, junction capacitance for switching speed, and compatibility with automated SMT assembly on FR-4 with 2 oz copper.
Technical Context
This Schottky rectifier uses a planar metal-silicon junction optimized for low VF and controlled IR across -55°C to +150°C. Its 30 °C/W typical RθJC (Note 6) and 60 °C/W RθJA (Note 6) reflect performance on a 1-inch² copper pad - critical for thermally constrained portable designs.
Electrical behavior is characterized by VF = 420–610 mV at IF = 4 A (25°C), IR ≤ 150 µA at VR = 40 V (25°C), and CT = 88 pF at VR = 4 V / 1 MHz - enabling efficient operation in 100 kHz–1 MHz boost and buck topologies with minimal switching loss.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRRM | 40 V - Maximum repetitive reverse voltage before breakdown; sets safe operating limit in 3.3 V–24 V input rails. |
| IO | 4 A - Average rectified output current on 1-inch² copper pad; defines continuous DC conduction capability. |
| VF max | 0.61 V @ 4 A - Peak forward voltage determining conduction loss (≤2.44 W dissipation at full load). |
| IR max | 150 µA @ 40 V - Reverse leakage at max rated voltage; impacts standby power in always-on circuits. |
| RθJA (Note 6) | 60 °C/W - Thermal resistance to ambient on 1-inch² pad; enables ~2.2 W total power dissipation at TA = 25°C. |
| Junction Capacitance | 88 pF @ 4 V - Low capacitance minimizes reverse recovery charge and EMI in high-frequency switching. |
Pinout & Package
Package: X3-TSN1608-2 - ultra-compact surface-mount case (1.60 × 0.80 × 0.25 mm), 0.0007 g weight, NiAu-plated terminals, cathode dot marking, moisture sensitivity level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal during forward conduction | Connected to lower-potential node (e.g., switch node in boost); requires thermal pad connection per recommended layout. |
| Cathode | Current exit terminal during forward conduction | Connected to higher-potential rail (e.g., output capacitor positive); marked with dot; electrically isolated side walls must avoid solder contact. |
Key Features
| Feature | Design Value |
|---|---|
| Low VF at 4 A | 0.61 V max reduces conduction loss by ≥15% vs. standard Schottkys, directly improving efficiency in 1–3 W portable supplies. |
| Reduced high-temp IR | Leakage remains ≤50 µA at 125°C/40 V - mitigates thermal runaway risk in sealed enclosures or hot ambient environments. |
| Ultra-small footprint | 1.28 mm² area (1.60 × 0.80 mm) saves space vs. SMA/SMB packages - critical for wearables and compact IoT modules. |
| Lead-free & Green | Fully RoHS 3 compliant, halogen/antimony/beryllium free (<900 ppm Br+Cl, <1000 ppm Sb/Be) - meets automotive and medical regulatory requirements. |
Applications
| USB Power Delivery Adapter | Wireless Charging Transmitter |
|---|---|
Use Scenario: Output rectification in 20–30 W GaN-based USB-PD adapters with 100–300 kHz switching frequency. IC Role / Device Role / Timing Role: Secondary-side synchronous rectifier replacement; blocks reverse current while minimizing forward loss. Use Value: 0.61 V VF at 4 A cuts conduction loss by ~0.3 W vs. legacy Schottkys, enabling smaller heatsinks and tighter thermal margins. |
Use Scenario: Reverse polarity protection and boost diode in Qi-compliant 15 W transmitter boards with multi-coil layouts. IC Role / Device Role / Timing Role: Unidirectional current gate between DC input and resonant tank driver stage. Use Value: 150 µA IR at 40 V prevents >10 µW standby drain in always-on control circuitry, extending sleep-mode battery life. |
| Portable Medical Monitor | Industrial Bluetooth Sensor Node |
Use Scenario: Battery reverse connection protection in handheld ECG units powered by single-cell Li-ion (3.0–4.2 V). IC Role / Device Role / Timing Role: Series-blocking diode in main power path; conducts only during correct battery insertion. Use Value: 0.42 V typical VF at 1 A ensures <0.42 V dropout - preserving >90% of battery voltage for analog front-end precision. |
Use Scenario: Boost converter output rectifier in energy-harvesting nodes using solar or thermal sources (2–5 V input). IC Role / Device Role / Timing Role: High-efficiency rectifier in 500 kHz flyback-derived topology delivering 3.3 V to BLE SoC. Use Value: 88 pF junction capacitance limits reverse recovery charge to <1 nC - reducing EMI and enabling clean RF coexistence. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Schottky rectifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SS34H (Vishay) | 40 V / 3 A, VF = 0.55 V max @ 3 A, RθJA = 70 °C/W (on same pad), larger SMA package (4.3 × 2.6 mm). | Lower current rating limits use in >3 A continuous paths; higher thermal resistance requires larger copper area for equivalent dissipation. | Select when cost sensitivity outweighs size constraints and peak current stays ≤3 A. |
| RB055LAM-30 (ROHM) | 30 V / 4 A, VF = 0.45 V max @ 4 A, but VRRM insufficient for 40 V transient clamping in 24 V systems. | Not suitable for 40 V-rated input stages; acceptable only in ≤30 V nominal rails with tight overvoltage control. | Choose only if system maximum reverse voltage is confirmed ≤30 V and lowest possible VF is prioritized. |
Compared with SS34H and RB055LAM-30, SDM4A40EP3-7B uniquely balances 4 A current, 40 V rating, sub-0.61 V VF, and 1.28 mm² footprint - making it optimal for space-constrained, thermally sensitive 24 V portable power designs where both voltage margin and efficiency matter.
Availability
SDM4A40EP3-7B is available at Aetrix Electronics and suitable for USB PD adapters, wireless charging transmitters, portable medical monitors, and industrial Bluetooth sensor nodes requiring stable component supply and consistent thermal performance across production volumes.
Supply support for SDM4A40EP3-7B 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, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.
SDM4A40EP3-7B belongs to Diodes' high-efficiency Schottky rectifier product line, engineered specifically for space- and thermal-constrained portable power conversion - emphasizing low VF, controlled IR, and ultra-miniature packaging for next-generation wearables and IoT edge devices.
FAQ
What is the maximum continuous forward current for SDM4A40EP3-7B on a standard PCB?
The SDM4A40EP3-7B supports 4 A average rectified output current when mounted on an FR-4 board with a 1-inch² copper pad (per Note 6). On minimum pad layout (Note 5), derating applies: IO drops to 1.5 A due to higher RθJA (160 °C/W) and reduced heat spreading.
Does SDM4A40EP3-7B meet AEC-Q101 requirements for automotive use?
No - SDM4A40EP3-7B is not AEC-Q101 qualified. Diodes offers automotive-grade variants (e.g., SDM4A40Q3-7B) with PPAP documentation, IATF 16949 manufacturing, and extended temperature validation. This part is intended for commercial/industrial portable applications.
How does the X3-TSN1608-2 package affect PCB assembly?
The X3-TSN1608-2 has electrically active bare silicon side walls. Contact with solder or flux during reflow must be avoided - strict adherence to recommended stencil aperture and placement accuracy is required to prevent shorting or parametric shift.
Can SDM4A40EP3-7B replace a standard SMA-packaged Schottky in existing designs?
Direct replacement is not mechanically feasible: X3-TSN1608-2 (1.6 × 0.8 mm) is ~70% smaller than SMA (4.3 × 2.6 mm). Layout redesign is mandatory - including new footprints, thermal pads, and solder mask definition - though electrical behavior (VF, IR, VRRM) is compatible.
SDM4A40EP3-7B Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- 0603 (1608 Metric)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Technology:
- Schottky
- Voltage - DC Reverse (Vr) (Max):
- 40 V
- Current - Average Rectified (Io):
- 4A
- Voltage - Forward (Vf) (Max) @ If:
- 610 mV @ 4 A
- Speed:
- Fast Recovery =< 500ns, > 200mA (Io)
- Reverse Recovery Time (trr):
- -
- Current - Reverse Leakage @ Vr:
- 150 µA @ 40 V
- Capacitance @ Vr, F:
- 88pF @ 4V, 1MHz
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- X3-TSN1608-2
- Operating Temperature - Junction:
- -55°C ~ 150°C
SDM4A40EP3-7B FAQ
1.How can I place an order for SDM4A40EP3-7B through Aetrix?
Please submit a Request for Quotation (RFQ) for SDM4A40EP3-7B 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 SDM4A40EP3-7B reliable?
The price and inventory of SDM4A40EP3-7B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SDM4A40EP3-7B is usually 5 days.
3.What payment methods are accepted for SDM4A40EP3-7B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SDM4A40EP3-7B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SDM4A40EP3-7B?
SDM4A40EP3-7B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SDM4A40EP3-7B 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 SDM4A40EP3-7B?
For technical support, including SDM4A40EP3-7B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SDM4A40EP3-7B requirements.
6.How does Aetrix verify that SDM4A40EP3-7B is sourced from the original manufacturer or authorized distributors?
All SDM4A40EP3-7B 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 SDM4A40EP3-7B meets industry standards.
7.What is the process for return or replacement of SDM4A40EP3-7B?
All SDM4A40EP3-7B units undergo pre-shipment inspection (PSI). If there is an issue with SDM4A40EP3-7B, 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 SDM4A40EP3-7B part is unused and in its original packaging.
Return procedure for SDM4A40EP3-7B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SDM4A40EP3-7B Tags
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Diodes Incorporated
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