Vishay General Semiconductor - Diodes Division GBU8M-M3/45

Overview

GBU8M-M3/45 from Vishay General Semiconductor is a glass passivated single-phase bridge rectifier in GBU case style, rated for 1000 V repetitive peak reverse voltage (V_RRM), 8.0 A average forward output current (I_F(AV)), and 200 A non-repetitive surge current (I_FSM). It delivers low 1.0 V forward voltage drop at 8.0 A and supports PCB mounting with 0.5" × 0.5" copper pads for power supplies in TVs, printers, and switching-mode adapters.

For engineers reviewing the GBU8M-M3/45 datasheet, GBU8M-M3/45 pinout, GBU8M-M3/45 application, or GBU8M-M3/45 equivalent, key selection criteria include its 1000 V blocking capability, halogen-free RoHS-compliant M3 termination, 150 °C maximum junction temperature, and verified thermal resistance of 20 °C/W (R_θJA) under PCB-mount conditions.

Technical Context

The GBU8M-M3/45 implements a full-wave in-line bridge configuration with four silicon diodes arranged as a single-phase AC-to-DC converter. Its glass passivation ensures stable reverse leakage (5 μA max at 25 °C) and high dielectric strength (1500 V_RMS case isolation).

Designed for conduction in both half-cycles of input AC, it operates with fixed polarity output (+ and – terminals marked on case) and requires no external control logic. Thermal performance is defined for two mounting conditions: heatsink-mounted (R_θJC = 4.0 °C/W) and PCB-mounted (R_θJA = 20 °C/W) with specified copper pad area and lead length.

Key Specifications

Pinout & Package

Package: GBU case style - molded UL 94 V-0 compound, matte tin-plated leads, halogen-free (M3 suffix), 0.720–0.740" length, 0.190–0.210" width, 0.130–0.140" height, beveled corner indicating positive output terminal.

Key Features

Applications

Equivalent & Alternatives

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

Compared with GBU8K-M3/45 and KBU8M, the GBU8M-M3/45 provides optimal balance of high-voltage robustness (1000 V), compact GBU packaging, and industry-leading thermal resistance (20 °C/W) - making it preferred for modern, dense, and globally compliant AC/DC front-ends.

Availability

GBU8M-M3/45 is available at Aetrix Electronics and suitable for monitor power supplies, printer mainboards, audio equipment power stages, and home appliance control boards requiring stable component supply and halogen-free compliance.

Supply support for GBU8M-M3/45 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

Vishay General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, MOSFETs, and optoelectronics with emphasis on reliability, efficiency, and regulatory compliance.

The GBU series was engineered for high-surge, high-voltage AC/DC conversion in cost-sensitive consumer and industrial power supplies - prioritizing ruggedness, solderability, and long-term stability under thermal cycling.

FAQ

What is the maximum operating junction temperature for GBU8M-M3/45?

The GBU8M-M3/45 has a maximum junction temperature (T_J) of +150 °C, validated across its full operating range. This allows sustained operation in thermally demanding environments such as enclosed power supplies or high-ambient industrial settings. Derating curves in the Vishay datasheet (Doc. #88616) define safe current limits at elevated temperatures, and the device maintains rated performance up to this limit when mounted per specification - e.g., on a heatsink (R_θJC = 4.0 °C/W) or on PCB with 12 mm × 12 mm copper pads (R_θJA = 20 °C/W). The GBU8M-M3/45 must not exceed this temperature during steady-state or transient conditions.

Does GBU8M-M3/45 support wave soldering, and what are the limits?

Yes, the GBU8M-M3/45 is qualified for wave soldering per JESD 22-B106: maximum solder dip temperature is 275 °C for up to 10 seconds. Its matte tin-plated leads meet J-STD-002 and JESD 22-B102 solderability standards, and the UL 94 V-0 molding compound resists thermal degradation under these conditions. The M3 suffix confirms halogen-free construction, which further enhances process compatibility and environmental compliance. For reliable assembly, ensure preheat profiles avoid thermal shock, and verify that board-level dwell time within the 275 °C zone does not exceed the 10 s limit. The GBU8M-M3/45 remains fully functional post-soldering when these parameters are observed.

How does the GBU8M-M3/45 differ from GBU8M-E3/45?

The GBU8M-M3/45 and GBU8M-E3/45 share identical electrical ratings, package dimensions, and thermal characteristics, but differ in material composition and compliance: M3 denotes halogen-free, RoHS-compliant construction meeting JEDEC JESD201 Class 1A whisker requirements, while E3 indicates standard RoHS compliance without halogen-free assurance. Both are UL recognized (E54214) and rated for 1000 V_RRM and 8.0 A I_F(AV). The GBU8M-M3/45 is specified for environmentally regulated markets (e.g., EU, Japan, China RoHS II), whereas GBU8M-E3/45 suits general commercial applications where halogen content is unrestricted. Pinout, mounting torque (5.7 cm-kg), and polarity marking are identical for both variants.

What is the reverse leakage current of GBU8M-M3/45 at elevated temperature?

The GBU8M-M3/45 exhibits a maximum DC reverse current (I_R) of 5.0 μA at 25 °C and rated V_DC = 1000 V, rising to 500 μA at 125 °C under the same voltage. This temperature-dependent leakage is inherent to silicon PN junctions and is fully characterized in the Vishay datasheet (Fig. 4). At 150 °C - the absolute maximum junction temperature - leakage remains within predictable bounds and does not compromise blocking integrity in typical applications. Designers should account for this increase in high-temperature standby modes, especially in energy-sensitive systems. The GBU8M-M3/45 maintains stable performance across this range due to its glass passivation layer, which suppresses surface conduction paths.

Can GBU8M-M3/45 be mounted directly to a heatsink, and what is the recommended torque?

Yes, the GBU8M-M3/45 is designed for direct heatsink mounting using the case as the thermal path, with recommended mounting torque of 5.7 cm-kg (5 inch-lbs); maximum allowable torque is 10 cm-kg (8.8 inch-lbs). Mounting requires #6 screws and silicone thermal compound to minimize interfacial thermal resistance. In this configuration, its junction-to-case thermal resistance (R_θJC) is 4.0 °C/W - significantly lower than the 20 °C/W for PCB-only mounting. Mechanical data specify a 9° chamfer and flat base for uniform pressure distribution. Proper torque prevents case cracking or lead fracture while ensuring optimal heat transfer. The GBU8M-M3/45 achieves highest power handling in this mode, supporting full 8.0 A I_F(AV) at T_C = 60 °C.