Diodes Incorporated UF1502S-B

Overview

UF1502S-B from Diodes Incorporated is a 100V peak repetitive reverse voltage ultra-fast rectifier diode in DO-41 package, rated for 1.5A average forward current and 50A non-repetitive surge current, with 1.3V forward voltage at 1.5A and 75ns reverse recovery time - used in high-frequency switch-mode power supply output stages.

For engineers reviewing the UF1502S-B datasheet, UF1502S-B pinout, UF1502S-B application, or UF1502S-B equivalent, key selection criteria include V_RRM = 100V, I_O = 1.5A @ T_A = 50°C, t_rr = 75ns, V_F = 1.3V @ I_F = 1.5A, and R_θJA = 70°C/W thermal resistance.

Technical Context

This ultra-fast rectifier employs a diffused junction structure to achieve low reverse leakage (≤100µA at 100°C) and fast switching performance. Its 75ns reverse recovery time enables efficient operation in 50–500kHz SMPS topologies where reduced switching loss is critical.

The device is optimized for single-phase, half-wave rectification under resistive or inductive loads at 60Hz, with derating required for capacitive loads. Thermal design must account for its 70°C/W junction-to-ambient thermal resistance and 1.5A current rating only when leads are held at ambient temperature at 9.5mm from case.

Key Specifications

Pinout & Package

DO-41 molded plastic package with axial leads; cathode indicated by band marking; lead finish is matte tin; RoHS-compliant; weight ≈ 0.35 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH1L06 and ES1J, UF1502S-B offers optimal balance of 100V rating, 1.5A current capacity, and 75ns speed for secondary-side SMPS rectification - minimizing both conduction and switching losses without over-specifying voltage or sacrificing thermal margin.

Availability

UF1502S-B is available at Aetrix Electronics and suitable for AC-DC adapters, DC-DC converter secondary stages, and LED driver output rectification requiring stable component supply and consistent DO-41 mechanical form factor.

Supply support for UF1502S-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 US.

The UF150xS series belongs to Diodes' ultra-fast rectifier product line, engineered specifically for high-efficiency, high-frequency power conversion in consumer, industrial, and automotive power supplies.

FAQ

What is the maximum operating temperature for UF1502S-B?

The UF1502S-B has an operating and storage temperature range of −65°C to +150°C. Its electrical ratings assume thermal management maintains junction temperature within this limit; at 1.5A continuous current, ambient must be ≤50°C with leads held at ambient at 9.5mm from case per derating curve.

Is UF1502S-B RoHS compliant?

Yes, UF1502S-B features a lead-free finish and is RoHS compliant per EU Directive 2002/95/EC, with all applicable exemptions applied. The tin-plated leads meet MIL-STD-202 Method 208 solderability requirements.

Can UF1502S-B replace UF1501S in existing designs?

Yes - UF1502S-B shares identical DO-41 package, pinout, and thermal characteristics with UF1501S, differing only in V_RRM (100V vs. 50V) and V_F (1.3V vs. 1.0V). It can be used as a drop-in upgrade where higher reverse voltage margin is needed, provided forward voltage increase is acceptable.

What is the typical total capacitance of UF1502S-B?

The typical total capacitance is 20 pF, measured at 1.0 MHz with 4.0 V DC reverse bias. This low capacitance minimizes high-frequency noise coupling and improves EMI performance in switching power supplies.