Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Diodes > Rectifiers > Single Diodes

Diodes Incorporated SD845-T

Name: SD845-T
Brand: Diodes Incorporated
SKU: SD845-T
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: SD845-T

Manufacturer:: Diodes Incorporated

Category:: Single Diodes

Package:: DO-201AD, Axial

Datasheet:: SD845-T.pdf

Description:: DIODE SCHOTTKY 45V 8A DO201AD

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:8,863

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

SD845-T from Diodes Incorporated is a 40 V, 8.0 A Schottky barrier rectifier in DO-201AD package, featuring 0.7 V max forward voltage at 8 A, 100 µA max reverse leakage at rated V_RRM, and 175 A non-repetitive surge current capability. It is designed for high-efficiency DC/DC output rectification in industrial power supplies and AC-DC adapters.

For engineers reviewing the SD845-T datasheet, SD845-T pinout, SD845-T application, or SD845-T equivalent, key selection criteria include its 40 V blocking rating, low VF trade-off vs. leakage at elevated temperature, DO-201AD thermal resistance (30 °C/W junction-to-lead), and guard ring–enabled transient robustness in high-surge environments.

Technical Context

This device operates as a unidirectional power rectifier with metal–semiconductor junction architecture, optimized for minimal conduction loss in continuous forward-biased operation. Its guard ring structure provides edge termination to suppress surface leakage and improve dv/dt immunity during switching transients.

Electrical behavior is characterized by strong temperature dependence: IR rises from ≤100 µA at +25°C to ≤50 mA at +100°C under full V_RRM, while VF decreases slightly with rising junction temperature-typical VF is 0.55 V at +25°C and ~0.48 V at +125°C (IF = 8 A).

Key Specifications

Parameter	Value and Actual Design Meaning
V_RRM	40 V - Maximum repetitive reverse voltage before breakdown; sets upper limit for circuit voltage margin in 24 V nominal systems.
I_O	8 A - Average forward rectified current at +25°C case temperature; derates to ~4.5 A at +100°C per Figure 1.
V_F max	0.7 V @ 8 A, +25°C - Directly determines conduction loss: 5.6 W dissipation at full load, critical for thermal design.
I_R max	100 µA @ 40 V, +25°C - Low leakage preserves efficiency in standby; rises to 50 mA at +100°C, limiting high-temp hold-up performance.
I_FSM	175 A @ 8.3 ms - Supports single-cycle AC line surge events without failure; enables use without upstream fusing in many adapter designs.
R_θJL	30 °C/W - Junction-to-lead thermal resistance with 9.5 mm lead length; defines minimum copper area needed on PCB for thermal management.
C_J	550 pF @ 4 V, 1 MHz - Junction capacitance affects high-frequency switching noise and EMI filter sizing in SMPS outputs.

Pinout & Package

DO-201AD package: axial-leaded, molded plastic case (UL 94V-0), cathode band marking, 1.1 g mass, lead finish – bright tin, solderable per MIL-STD-202 Method 208.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Forward current entry node	Connected to transformer secondary or switch-node side; must withstand peak inverse voltage and surge current.
Cathode	Forward current exit node	Connected to output capacitor and load; carries full DC output current and defines ground reference for output sensing.

Key Features

Feature	Design Value
Guard ring structure	Provides edge termination to suppress surface leakage paths and improve transient voltage immunity up to 175 A surge.
Low V_F (0.55 V typ)	Reduces conduction loss by >30% vs. comparable Si diodes, enabling higher efficiency in 12–24 V output rails.
DO-201AD package	Enables vertical mounting with 30 °C/W thermal resistance; compatible with standard axial through-hole assembly and wave soldering.
RoHS-compliant finish	Bright tin plating meets EU Directive 2011/65/EU and supports lead-free reflow and hand-soldering processes.

Applications

AC-DC Adapter Output Rectification

Industrial DC/DC Converter Secondary Side

Use Scenario: 24 V, 5 A offline adapter powering PLC I/O modules with 100–240 VAC input.

IC Role / Device Role / Timing Role: Primary output rectifier converting high-frequency transformer secondary voltage to regulated DC bus.

Use Value: 0.7 V V_F limits conduction loss to 3.5 W, reducing heatsink requirement and improving no-load efficiency over Si alternatives.

Use Scenario: 12 V, 6 A isolated DC/DC module in motor drive control board with 48 V input.

IC Role / Device Role / Timing Role: Synchronous rectifier replacement in asymmetrical half-bridge topology operating at 250 kHz.

Use Value: 175 A I_FSM withstands startup inrush and short-circuit recovery surges without degradation.

Telecom Power Supply Hold-Up

LED Driver Secondary Rectification

Use Scenario: 48 V telecom shelf supply requiring 20 ms hold-up time during AC dropout.

IC Role / Device Role / Timing Role: Main output rectifier feeding bulk capacitor bank; operates continuously at 8 A average load.

Use Value: 30 °C/W R_θJL allows direct lead-to-heatsink mounting, maintaining T_J < 125°C without forced air.

Use Scenario: Constant-current LED driver for street lighting with 36 V output and 700 mA load.

IC Role / Device Role / Timing Role: Output rectifier in flyback converter delivering ripple-sensitive DC to LED string.

Use Value: 550 pF C_J minimizes high-frequency ringing at MOSFET turn-off, reducing EMI filter component count.

Equivalent & Alternatives

The following parts are listed as comparable options for similar Schottky rectifier applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
SS84	Same DO-201AD package, 40 V V_RRM, but 0.85 V V_F max @ 8 A and 200 µA I_R @ +25°C.	Higher conduction loss reduces efficiency in thermally constrained adapters; acceptable where leakage sensitivity is low.	Select SS84 only if cost is primary constraint and thermal margin exceeds 15°C.
MBR845	45 V V_RRM, same 8 A I_O, 0.75 V V_F max, but TO-220AC package with lower R_θJA (50 °C/W vs. DO-201AD's 75 °C/W).	Requires PCB footprint change and heatsink mounting; better for high-ambient industrial environments (>60°C).	Choose MBR845 when ambient exceeds 60°C and board space permits TO-220 layout.

Compared with SS84 and MBR845, SD845-T delivers optimal balance of low V_F, moderate leakage, and compact DO-201AD packaging-making it preferred for space-constrained, efficiency-critical 24–48 V output stages where thermal management relies on lead conduction rather than heatsinks.

Availability

SD845-T is available at Aetrix Electronics and suitable for industrial power supplies, telecom rectifiers, and LED driver secondary-side rectification requiring stable component supply and long-term manufacturing continuity.

Supply support for SD845-T 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 SD8xx series belongs to Diodes' high-current Schottky rectifier product line, engineered specifically for high-efficiency, high-surge-output stages in AC-DC and isolated DC-DC converters targeting industrial and computing power applications.

FAQ

What is the maximum allowable junction temperature for SD845-T?

The SD845-T has an operating junction temperature range of −65°C to +150°C. Continuous operation above +150°C risks irreversible parametric shift and premature failure. Thermal design must ensure T_J remains within this limit using the specified R_θJL = 30 °C/W and measured lead temperature.

Does SD845-T support lead-free soldering processes?

Yes. SD845-T features bright tin-plated leads compliant with RoHS Directive 2011/65/EU and qualified for lead-free reflow soldering per JEDEC J-STD-020C Level 1 moisture sensitivity. No pre-baking is required prior to standard Pb-free reflow profiles.

How does the guard ring improve reliability in real-world applications?

The integrated guard ring suppresses surface leakage currents and prevents premature edge breakdown during fast dv/dt transients-such as those caused by MOSFET switching or lightning-induced surges. This extends operational life in AC-DC adapters exposed to line disturbances and improves consistency in high-volume manufacturing.

Can SD845-T replace a 60 V Schottky rectifier like SD860 in a 40 V circuit?

No. While SD845-T's 40 V V_RRM suffices for nominal 40 V circuits, it lacks the 60 V margin required for SD860's intended use cases-such as 48 V systems with 20% line tolerance (57.6 V) plus transient overshoot. Substituting SD845-T risks reverse-bias avalanche failure under worst-case conditions.

SD845-T Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: DO-201AD, Axial

Packaging:: Tape & Reel (TR)

Product Status:: Obsolete

Technology:: Schottky

Voltage - DC Reverse (Vr) (Max):: 45 V

Current - Average Rectified (Io):: 8A

Voltage - Forward (Vf) (Max) @ If:: 550 mV @ 8 A

Speed:: Fast Recovery =< 500ns, > 200mA (Io)

Reverse Recovery Time (trr):: -

Current - Reverse Leakage @ Vr:: 1 mA @ 45 V

Capacitance @ Vr, F:: 550pF @ 4V, 1MHz

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: DO-201AD

Operating Temperature - Junction:: -65°C ~ 150°C

SD845-T FAQ

1.How can I place an order for SD845-T through Aetrix?

Please submit a Request for Quotation (RFQ) for SD845-T 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 SD845-T reliable?

The price and inventory of SD845-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SD845-T is usually 5 days.

3.What payment methods are accepted for SD845-T?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SD845-T transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for SD845-T?

SD845-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your SD845-T 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 SD845-T?

For technical support, including SD845-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SD845-T requirements.

6.How does Aetrix verify that SD845-T is sourced from the original manufacturer or authorized distributors?

All SD845-T 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 SD845-T meets industry standards.

7.What is the process for return or replacement of SD845-T?

All SD845-T units undergo pre-shipment inspection (PSI). If there is an issue with SD845-T, 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 SD845-T part is unused and in its original packaging.

Return procedure for SD845-T:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

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…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

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…

2026-08-14 Jumper Cables: How to Use, Connect and Choose Them Safely

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…

2026-08-11 LDO Regulator: Dropout Voltage, Noise, PSRR and Power Dissipation

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…

2026-08-06 Conditional Access Module: CAM, CI/CI+ and DVB Security

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…

2026-08-03 Electronic Component Obsolescence: EOL Risks, Replacement Options and Last-Time Buy Strategy

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.

2026-07-29 18650 Battery: Voltage, Capacity, Charging and Pack Design

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.…

2026-07-27 Hall Effect Sensor: Working Principle, Types, Circuits and Applications

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…

2026-07-20 Product Change Notification (PCN) in Electronic Components: Meaning and Supply Chain Response

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…

2026-07-19 Blend Door Actuator: Symptoms, Location, Reset and Replacement Guide

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…