Fuji 7MBR50SB120-50

7MBR50SB120-50 | 1200V 50A 7-in-1 IGBT Module In-Depth Review

Content last revised on October 7, 2025.

Product Overview: A Compact Powerhouse for Motor Drives

Defining Thermal Reliability and Integration at 1200V

The Fuji Electric 7MBR50SB120-50 is a highly integrated 7-in-1 IGBT module, engineered for exceptional thermal reliability and power density in compact motor control systems. With its core specifications of 1200V | 50A | Tj max 175°C, this module delivers robust performance through two key engineering benefits: superior thermal margin and significantly simplified system design. It directly addresses the challenge of building powerful, efficient, and reliable inverters within space-constrained enclosures by consolidating a three-phase inverter and brake chopper into a single component. For systems requiring high power density and simplified assembly, the integrated nature of this module offers a distinct advantage over discrete solutions.

Key Parameter Overview

Decoding the Specs for Enhanced Thermal Reliability

The technical specifications of the 7MBR50SB120-50 are foundational to its performance in demanding applications. The parameters are organized below by functional block to facilitate system-level evaluation.

Download the 7MBR50SB120-50 datasheet for detailed specifications and performance curves.

Application Scenarios & Value

Achieving System-Level Benefits in High-Density Motor Control

The 7MBR50SB120-50 is best suited for applications where performance, reliability, and a compact footprint are critical design drivers. For systems demanding high efficiency and robust thermal management in a compact form factor, this 1200V, 50A module is an optimal choice.

A prime engineering scenario is in the development of advanced Servo Drive systems for multi-axis CNC machinery or robotics. In these applications, multiple drives are often packed into a single, tightly sealed cabinet, making thermal management a primary challenge. The 7MBR50SB120-50's high maximum junction temperature of 175°C provides a crucial thermal margin. This allows engineers to design smaller, more cost-effective heatsinks or to operate the system reliably at higher ambient temperatures without derating performance. Furthermore, its 7-in-1 integration simplifies the power stage design, reducing PCB complexity, minimizing assembly points of failure, and lowering electromagnetic interference (EMI) by shortening high-current pathways. The integrated brake chopper circuit is essential for controlling motor deceleration in dynamic applications, a function that would otherwise require additional external components.

While this module is well-positioned for 50A applications, for lower-power systems, the related 7MBR25SA120-50 offers a similar integrated topology with a 25A rating. Conversely, for applications requiring higher current handling, the 7MBR75VB120-50 provides a 75A capability.

Technical Deep Dive

A Closer Look at Thermal Performance and Its Design Implications

A key differentiator for the 7MBR50SB120-50 is its operational ceiling of 175°C (Tj max). This is not just a number; it is a direct enabler of power density and system reliability. To understand its impact, one must consider its relationship with the module's thermal resistance, Rth(j-c). Think of thermal resistance like the width of a pipe: a lower Rth value is like a wider pipe, allowing more heat to flow away from the semiconductor chip (the junction) to the module's case for a given temperature difference.

With a maximum Rth(j-c) of 0.38 °C/W for the inverter IGBTs, engineers can accurately calculate the temperature rise under specific load conditions. The high Tj max provides a larger budget for this temperature rise, giving designers flexibility. This can be leveraged in two ways: either push more power through the module while staying within safe limits or use a smaller, less expensive heatsink for the same power level, thereby reducing overall system size and cost. This thermal robustness is critical for applications in industrial automation where systems are expected to operate flawlessly for years in demanding environments. For a detailed guide on interpreting these values, see our article on decoding IGBT datasheets.

Frequently Asked Questions (FAQ)

How does the 175°C maximum junction temperature (Tj max) of the 7MBR50SB120-50 directly impact the thermal design of a power converter?

The high Tj max of 175°C provides a significant thermal headroom. This allows engineers to design for higher power output in a given footprint, utilize smaller and more cost-effective heatsinks, or ensure greater reliability and longer operational life by running the device at a lower percentage of its maximum thermal limit during normal operation.

What is the engineering advantage of the integrated NTC thermistor in the 7MBR50SB120-50 module?

The integrated NTC thermistor provides a direct, real-time method for monitoring the module's internal temperature. This feedback is critical for implementing an effective over-temperature protection (OTP) scheme in the controller's logic, preventing thermal runaway and catastrophic failure, which is a cornerstone of designing reliable robotic servo drives.

System Design & Integration

To leverage the full capabilities of the 7MBR50SB120-50, please contact our technical specialists for assistance with application-specific inquiries and design considerations.