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 UF1503S-B

Name: UF1503S-B
Brand: Diodes Incorporated
SKU: UF1503S-B
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: UF1503S-B

Manufacturer:: Diodes Incorporated

Category:: Single Diodes

Package:: DO-204AL, DO-41, Axial

Datasheet:: UF1503S-B.pdf

Description:: DIODE GEN PURP 200V 1.5A DO41

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:6,330

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

Product details

Overview

UF1503S-B from Diodes Incorporated is a 1.5A ultra-fast rectifier diode in DO-41 package, rated for 200V peak repetitive reverse voltage (V_RRM), with 1.7V forward voltage at 1.5A and 50ns reverse recovery time (t_rr). It serves as a primary AC/DC input stage rectifier in offline switch-mode power supplies requiring high efficiency and low switching loss.

For engineers reviewing the UF1503S-B datasheet, UF1503S-B pinout, UF1503S-B application, or UF1503S-B equivalent, key selection criteria include V_RRM=200V, t_rr=50ns, I_O=1.5A @ T_A=50°C, low I_RM (5.0µA @ 25°C), and DO-41 thermal resistance (R_θJA=70°C/W).

Technical Context

This device employs a diffused junction structure to achieve ultra-fast switching performance, minimizing reverse recovery charge (Q_rr) and enabling high-frequency operation up to 100kHz in flyback and forward converters. Its surge rating of 50A (8.3ms half-sine) supports inrush current handling during cold-start conditions.

The DO-41 molded plastic case (UL 94V-0) provides mechanical robustness and thermal path optimization, while the cathode-band polarity marking and tin-plated leads ensure reliable solderability per MIL-STD-202 Method 208. Reverse leakage remains tightly controlled at 5.0µA (25°C) and 100µA (100°C).

Key Specifications

Parameter	Value and Actual Design Meaning
V_RRM	200 V - Maximum non-repetitive reverse voltage before breakdown; sets safe operating limit in 115/230VAC input stages.
I_O	1.5 A @ T_A=50°C - Continuous DC output current capability with standard lead heatsinking (9.5mm from case).
V_FM	1.7 V @ I_F=1.5A - Forward conduction loss directly impacts power-stage efficiency and thermal design margin.
t_rr	50 ns - Ultra-fast recovery minimizes switching loss and EMI generation in high-frequency SMPS topologies.
I_FSM	50 A (8.3ms) - Withstands line surge and startup inrush without failure, reducing need for upstream fusing.
R_θJA	70 °C/W - Junction-to-ambient thermal resistance defines required PCB copper area and airflow for thermal management.

Pinout & Package

DO-41 axial-leaded package with cathode band marking; two-terminal device (anode and cathode). No internal bonding wires or multi-pin configuration.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Forward current entry point	Connected to AC input or transformer secondary; must withstand full reverse voltage when cathode is positive.
Cathode	Forward current exit / reverse blocking terminal	Marked with band; ties to output capacitor or switching node; reverse leakage flows here under blocking condition.

Key Features

Feature	Design Value
Ultra-fast recovery (50ns)	Enables >100kHz switching in PFC and DC/DC stages without excessive diode switching loss or snubber complexity.
Low reverse leakage (5.0µA @ 25°C)	Reduces standby power loss in no-load and light-load conditions critical for Energy Star compliance.
50A surge rating	Eliminates need for external NTC thermistors or inrush limiters in cost-sensitive consumer power adapters.
DO-41 RoHS-compliant packaging	Supports automated through-hole assembly and meets global environmental compliance without lead-free reflow concerns.

Applications

AC/DC Adapter Input Rectification

Offline Flyback Converter Output

Use Scenario: 115/230VAC-to-12VDC wall adapter powering IoT sensors and smart home devices.

IC Role / Device Role / Timing Role: Primary-side bridge or single-diode rectifier converting AC line to unregulated DC bus.

Use Value: 50ns t_rr reduces high-frequency ringing and EMI filter size; 1.7V V_FM limits conduction loss at 1.5A load.

Use Scenario: Secondary-side rectification in 24W industrial flyback supply for PLC I/O modules.

IC Role / Device Role / Timing Role: Freewheeling diode conducting during MOSFET off-time; handles discontinuous conduction mode (DCM) transitions.

Use Value: Low I_RM (5.0µA) prevents output voltage drift during light loads; DO-41 footprint simplifies layout and thermal relief.

UPS Battery Charging Circuit

LED Driver Input Stage

Use Scenario: Line-powered UPS charging NiCd/NiMH backup batteries in telecom access equipment.

IC Role / Device Role / Timing Role: Half-wave rectifier feeding linear or buck charger IC; blocks reverse current during battery discharge.

Use Value: 200V V_RRM accommodates 170V peak line voltage plus safety margin; 50A I_FSM survives grid transients.

Use Scenario: Constant-voltage LED driver for commercial downlights operating from universal AC input.

IC Role / Device Role / Timing Role: Input rectifier in passive PFC circuit with bulk capacitor; conducts only during voltage peaks.

Use Value: 70°C/W R_θJA allows direct mounting on FR-4 with minimal copper pour; 35pF C_T avoids resonance with EMI filter inductors.

Equivalent & Alternatives

The following parts are listed as comparable options for similar ultra-fast rectifier applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
STTH1L06U	V_RRM=600V, t_rr=50ns, V_F=1.7V @ 1A, SOD-123FL package	Higher voltage rating but lower current (1A); surface-mount only	Select when board space is constrained and 600V isolation is required; not drop-in for through-hole DO-41 layouts.
ON Semiconductor MUR120E	V_RRM=200V, t_rr=35ns, V_F=1.15V @ 1A, DO-41 package	Faster recovery and lower V_F, but rated only for 1A average current	Prefer for higher-efficiency 1A designs where 35ns t_rr improves EMI; verify thermal margin at 1.5A derating.

Compared with STTH1L06U and MUR120E, UF1503S-B uniquely balances 1.5A current capability, 200V rating, and 50ns speed in a legacy-compatible DO-41 through-hole package-making it optimal for cost-sensitive, medium-power AC/DC replacements where manual or wave-solder assembly is used.

Availability

UF1503S-B is available at Aetrix Electronics and suitable for AC/DC adapters, offline flyback converters, UPS battery chargers, and LED driver input stages requiring stable component supply and long-term manufacturability.

Supply support for UF1503S-B 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 and manufacturing operations across Asia and the Americas.

The UF150xS series belongs to Diodes' ultra-fast rectifier product line, engineered specifically for high-efficiency, high-reliability AC/DC front-end conversion in consumer, industrial, and computing power supplies.

FAQ

What is the maximum allowable junction temperature for UF1503S-B?

The absolute maximum junction temperature (T_J) is +150°C, as specified in the Thermal Characteristics table. Operation above this limit risks permanent degradation of the diffused junction. Derating curves in Figure 1 show that ambient temperature must be limited to ≤50°C to sustain 1.5A average current, assuming standard lead heatsinking per note 4.

Can UF1503S-B replace UF1502S-B in an existing design?

Yes, UF1503S-B is a direct upgrade from UF1502S-B (100V V_RRM) with identical DO-41 package, pinout, and thermal characteristics, but offers double the reverse voltage rating (200V). No layout or thermal changes are needed; it improves margin against line surges and 230VAC operation without increasing forward loss.

Is UF1503S-B suitable for synchronous rectification circuits?

No. UF1503S-B is a unidirectional silicon PN-junction rectifier, not a MOSFET-based synchronous rectifier. It lacks gate control, cannot be actively turned off, and exhibits fixed forward voltage drop and reverse recovery behavior. Synchronous rectification requires externally driven N-channel MOSFETs with precise timing control.

Does UF1503S-B meet JEDEC moisture sensitivity level (MSL) requirements for reflow?

No-UF1503S-B is rated MSL Level 1 per J-STD-020, meaning it has unlimited floor life and does not require dry-packaging or baking prior to wave or hand soldering. This reflects its DO-41 epoxy-molded construction, which is inherently moisture-resistant and intended for through-hole assembly, not reflow.

UF1503S-B Specifications

Product attributes: Attribute value

Manufacturer:: Diodes Incorporated

Series:: -

Package/Case:: DO-204AL, DO-41, Axial

Packaging:: Bulk

Product Status:: Obsolete

Technology:: Standard

Voltage - DC Reverse (Vr) (Max):: 200 V

Current - Average Rectified (Io):: 1.5A

Voltage - Forward (Vf) (Max) @ If:: 1 V @ 1.5 A

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

Reverse Recovery Time (trr):: 50 ns

Current - Reverse Leakage @ Vr:: 5 µA @ 200 V

Capacitance @ Vr, F:: 35pF @ 4V, 1MHz

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: DO-41

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

UF1503S-B FAQ

1.How can I place an order for UF1503S-B through Aetrix?

Please submit a Request for Quotation (RFQ) for UF1503S-B 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 UF1503S-B reliable?

The price and inventory of UF1503S-B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for UF1503S-B is usually 5 days.

3.What payment methods are accepted for UF1503S-B?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for UF1503S-B transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for UF1503S-B?

UF1503S-B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your UF1503S-B 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 UF1503S-B?

For technical support, including UF1503S-B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your UF1503S-B requirements.

6.How does Aetrix verify that UF1503S-B is sourced from the original manufacturer or authorized distributors?

All UF1503S-B 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 UF1503S-B meets industry standards.

7.What is the process for return or replacement of UF1503S-B?

All UF1503S-B units undergo pre-shipment inspection (PSI). If there is an issue with UF1503S-B, 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 UF1503S-B part is unused and in its original packaging.

Return procedure for UF1503S-B:

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…