My Inquiry
My Account
Diodes Incorporated SDT40B100ST
- Part No.:
- SDT40B100ST
- Manufacturer:
- Diodes Incorporated
- Category:
- Single Diodes
- Package:
- TO-220-3
- Datasheet:
-
SDT40B100ST.pdf
- Description:
- DIODE SCHOTTKY 100V 40A TO220-3
- Quantity:
- Payment:
- Shipping:
Inventory:9,275
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SDT40B100ST from Diodes Incorporated is a 40A, 100V trench Schottky rectifier diode in TO220AB package, featuring 0.79V typical forward voltage at 40A/25°C, 120µA max reverse leakage at 100V/25°C, and 250A non-repetitive surge rating - deployed as freewheel or output rectifier in high-efficiency DC-DC converters.
For engineers reviewing the SDT40B100ST datasheet, SDT40B100ST pinout, SDT40B100ST application, or SDT40B100ST equivalent, key selection criteria include thermal resistance (2°C/W junction-to-case), high-temperature leakage stability (≤30mA at 100V/125°C), soft switching behavior, and RoHS-compliant matte tin terminations on copper leadframe.
Technical Context
This device uses trench-based Schottky architecture to achieve low VF while maintaining superior high-temperature IR stability versus planar Schottky diodes. Its 2°C/W RθJC enables direct mounting to heatsinks for sustained 40A conduction at TC ≤ 100°C per derating curve.
Designed for unidirectional power conversion, it operates with soft reverse recovery (no stored charge) and exhibits 100pF typical junction capacitance at 1MHz/0V, supporting high-frequency switching up to 500kHz in synchronous rectifier or buck converter topologies.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRRM | 100 V - Maximum repetitive reverse blocking voltage without breakdown |
| IO(AV) | 40 A - Continuous average forward current at TC = 100°C with heatsink |
| VF Typ | 0.79 V @ 40A, 25°C - Directly reduces conduction loss in 12V/48V output stages |
| IR Max | 120 µA @ 100V, 25°C - Enables stable operation in high-impedance bias networks |
| IFSM | 250 A - Withstands inrush surges during hot-plug or startup in industrial PSUs |
| RθJC | 2 °C/W - Requires ≥50mm×50mm×23mm Al heatsink for full 40A rating |
| TJ Range | –55°C to +150°C - Supports under-hood automotive and outdoor telecom deployments |
Pinout & Package
TO220AB (Generic) package with 3-terminal configuration: Anode (pin 1), Cathode (pin 2), and metal tab (pin 3, electrically connected to cathode). Molded plastic case meets UL 94V-0; terminals are matte tin over copper, solderable per MIL-STD-202 Method 208.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (Lead) | Anode | Input terminal for forward conduction; connects to switching node or transformer secondary |
| Pin 2 (Lead) | Cathode | Output terminal; ties to output rail or ground return path in freewheel configuration |
| Metal Tab | Cathode (internally tied) | Provides low-inductance, high-current cathode connection and mechanical heatsinking surface |
Key Features
| Feature | Design Value |
|---|---|
| Trench Schottky structure | Enables 0.79V VF at 40A while limiting IR drift to ≤30mA at 125°C |
| Soft, fast switching | No reverse recovery charge (Qrr ≈ 0), eliminating switching spikes in high-dV/dt environments |
| High-temp leakage stability | IR remains <30mA at 100V/125°C - critical for hold-up time in AC-DC adapters |
| RoHS & Halogen-free | Meets EU RoHS 3 (2015/863/EU); Br+Cl <1500ppm, Sb <1000ppm - compliant for green manufacturing |
Applications
| Server VRM Output Rectification | Industrial DC-DC Converter |
|---|---|
Use Scenario: 48V-to-12V step-down converter delivering >300W in datacenter server power supplies. IC Role / Device Role / Timing Role: Primary output rectifier replacing MOSFET synchronous switch in cost-sensitive designs. Use Value: 0.79V VF minimizes conduction loss at 40A load, improving efficiency by ~1.2% vs. legacy 120V Schottky alternatives. | Use Scenario: 24V input, 5V/20A isolated DC-DC module for PLC I/O modules. IC Role / Device Role / Timing Role: Freewheel diode across primary-side flyback transformer snubber network. Use Value: Soft switching eliminates EMI spikes during turn-off, reducing need for ferrite beads and RC filters. |
| AC-DC Adapter Secondary | Telecom Power Shelf Rectification |
Use Scenario: 100W laptop adapter with universal AC input (90–264VAC). IC Role / Device Role / Timing Role: Secondary-side output rectifier in LLC resonant topology. Use Value: Stable 120µA IR at 25°C and <30mA at 125°C ensures consistent no-load regulation and standby power compliance. | Use Scenario: –48V telecom shelf with redundant 3kW rectifier modules. IC Role / Device Role / Timing Role: Blocking diode in OR-ing configuration between parallel rectifiers. Use Value: 100V VRRM and 250A IFSM support hot-swap redundancy without derating, enabling N+1 fault tolerance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Schottky rectifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Vishay VS-40CPH01-M3 | Same 100V/40A rating; VF = 0.72V @ 40A/25°C; RθJC = 2.5°C/W | Slightly lower VF but higher thermal resistance limits continuous current without larger heatsink | Prefer when board space allows larger heatsink and lowest possible conduction loss is prioritized |
| ON Semiconductor MBR40100CT | 100V/40A dual common-cathode; VF = 0.75V @ 20A/25°C per diode; TO220-3L | Dual configuration supports center-tapped transformer designs; not single-diode drop-in | Select only for dual-output or push-pull topologies requiring matched pair conduction |
Compared with VS-40CPH01-M3 and MBR40100CT, SDT40B100ST offers optimal balance of low VF (0.79V), tight thermal resistance (2°C/W), and single-diode simplicity - making it ideal for compact, high-power-density DC-DC outputs where layout area and thermal mass are constrained.
Availability
SDT40B100ST is available at Aetrix Electronics and suitable for server VRMs, industrial DC-DC converters, AC-DC adapters, and telecom power shelves requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for SDT40B100ST 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.
The SDT40B100ST belongs to Diodes' high-current trench Schottky rectifier product line, engineered specifically for high-efficiency, high-temperature power conversion in computing, industrial, and communications infrastructure.
FAQ
Is SDT40B100ST suitable for synchronous rectification replacement?
No - SDT40B100ST is a passive Schottky diode and cannot replace active synchronous rectifiers (e.g., MOSFETs with gate drivers). It serves as a self-commutated rectifier where control logic is absent, such as in flyback or LLC secondary-side rectification without driver circuitry.
What is the maximum case temperature for continuous 40A operation?
Per Figure 4, SDT40B100ST supports 40A average forward current only up to TC = 100°C with a 50mm×50mm×23mm aluminum heatsink. At TC = 125°C, IO derates to ~28A; operation beyond 150°C junction temperature violates absolute maximum ratings.
Does the metal tab require electrical isolation from the heatsink?
Yes - the metal tab is internally connected to the cathode (Pin 2), so dielectric isolation (e.g., mica washer or silicone pad) is mandatory when mounting to a grounded or non-cathode-referenced heatsink to prevent short circuits.
How does its leakage compare to standard silicon rectifiers at high temperature?
At 125°C and 100V, SDT40B100ST's IR is ≤30mA - significantly higher than silicon PN rectifiers (<100µA), but far lower than conventional Schottky diodes (>100mA). This controlled leakage enables predictable performance in high-temp DC-DC outputs without thermal runaway.
SDT40B100ST Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Tube
- Product Status:
- Active
- Technology:
- Schottky
- Voltage - DC Reverse (Vr) (Max):
- 100 V
- Current - Average Rectified (Io):
- 40A
- Voltage - Forward (Vf) (Max) @ If:
- 680 mV @ 20 A
- Speed:
- Fast Recovery =< 500ns, > 200mA (Io)
- Reverse Recovery Time (trr):
- -
- Current - Reverse Leakage @ Vr:
- 120 µA @ 100 V
- Capacitance @ Vr, F:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220-3
- Operating Temperature - Junction:
- -55°C ~ 150°C
SDT40B100ST FAQ
1.How can I place an order for SDT40B100ST through Aetrix?
Please submit a Request for Quotation (RFQ) for SDT40B100ST 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 SDT40B100ST reliable?
The price and inventory of SDT40B100ST are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SDT40B100ST is usually 5 days.
3.What payment methods are accepted for SDT40B100ST?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SDT40B100ST transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SDT40B100ST?
SDT40B100ST orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SDT40B100ST 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 SDT40B100ST?
For technical support, including SDT40B100ST datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SDT40B100ST requirements.
6.How does Aetrix verify that SDT40B100ST is sourced from the original manufacturer or authorized distributors?
All SDT40B100ST 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 SDT40B100ST meets industry standards.
7.What is the process for return or replacement of SDT40B100ST?
All SDT40B100ST units undergo pre-shipment inspection (PSI). If there is an issue with SDT40B100ST, 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 SDT40B100ST part is unused and in its original packaging.
Return procedure for SDT40B100ST:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SDT40B100ST Tags
-
1N4448X-TP
Micro Commercial Co
-
1N4148WX-TP
Micro Commercial Co
-
1N4148TR
onsemi
-
MMSD4148T1G
onsemi
-
MMBD914LT3G
onsemi
-
BAS16HT1G
onsemi
-
1N914BWT
onsemi
-
BAS21LT1G
onsemi
-
LL4148
onsemi
-
BAS16LT1G
onsemi
-
MMSD914T1G
onsemi
-
BAV21W-7-F
Diodes Incorporated
Tech Hub
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…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
