Diodes Incorporated UF1506S-B

Overview

UF1506S-B from Diodes Incorporated is a 1.5A ultra-fast rectifier diode in DO-41 package, rated for 800V peak repetitive reverse voltage (V_RRM), 50ns reverse recovery time (t_rr), and 1.7V forward voltage at 1.5A (V_FM). It serves as a primary-side switching rectifier in offline AC/DC power supplies and DC-DC flyback converters requiring high-speed recovery and low leakage.

For engineers reviewing the UF1506S-B datasheet, UF1506S-B pinout, UF1506S-B application, or UF1506S-B equivalent, key selection criteria include its 800V blocking capability, 50A non-repetitive surge rating (I_FSM), thermal resistance of 70°C/W, RoHS-compliant tin-plated leads, and DO-41 mechanical compatibility with legacy through-hole power designs.

Technical Context

This ultra-fast rectifier employs a diffused junction structure to achieve low reverse recovery charge (Q_rr) and minimal tail current-critical for reducing switching losses in high-frequency SMPS topologies operating up to 100 kHz. Its 50ns t_rr is measured under standardized conditions (I_F = 0.5A, I_R = 1.0A, I_rr = 0.25A), ensuring consistent performance across production lots.

The device supports 1.5A average rectified output current at T_A = 50°C with derating above that ambient, and exhibits only 100µA peak reverse current at 100°C under full 800V DC blocking-enabling reliable operation in thermally constrained industrial power adapters and auxiliary supplies.

Key Specifications

Pinout & Package

DO-41 molded plastic package (UL 94V-0), 0.35g mass, axial leads with cathode band marking. Tin-plated leads compliant with MIL-STD-202 Method 208.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH1L80 and ES1J, UF1506S-B uniquely balances 1.5A current capability, 50ns speed, and DO-41 compatibility-making it optimal for drop-in upgrades in existing 1A–1.5A ultra-fast rectifier layouts without board redesign or thermal derating.

Availability

UF1506S-B is available at Aetrix Electronics and suitable for offline AC/DC adapters, industrial flyback auxiliary supplies, and DC-DC boost input stages requiring stable component supply, consistent parametric performance, and long-term DO-41 footprint continuity.

Supply support for UF1506S-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.

UF1506S-B belongs to the UF150xS ultra-fast rectifier product line, engineered specifically for high-efficiency, high-reliability AC/DC and isolated DC-DC power conversion in consumer, industrial, and computing applications.

FAQ

What is the maximum allowable junction temperature for UF1506S-B?

The absolute maximum junction temperature is +150°C, as specified in the Thermal Characteristics table. Operation at this limit requires strict adherence to the derating curve in Figure 1: at 50°C ambient, full 1.5A current is permitted; above that, current must be linearly reduced to maintain T_J ≤ 150°C, assuming R_θJA = 70°C/W and no heatsink.

Can UF1506S-B replace UF1505S-B in an existing design?

Yes-UF1506S-B is a direct upgrade from UF1505S-B (600V V_RRM) with identical DO-41 package, pinout, and thermal characteristics, but offers 200V higher reverse blocking. No layout or thermal changes are needed; the increased margin improves reliability in high-line or transient-prone environments.

Is UF1506S-B suitable for use in synchronous rectification circuits?

No-UF1506S-B is a passive silicon PN-junction rectifier, not a MOSFET-based synchronous rectifier. It lacks gate control, body diode optimization, or low R_DS(on). For synchronous designs, discrete MOSFETs or dedicated SR controllers (e.g., AP3410, NCP4306) are required instead.

Does UF1506S-B meet automotive AEC-Q101 requirements?

No-UF1506S-B is not AEC-Q101 qualified. It is rated for industrial temperature range (−65°C to +150°C) and RoHS compliance, but lacks the stress testing, failure analysis, and traceability documentation required for automotive-grade qualification. Automotive applications require parts explicitly marked AEC-Q101.