7MBR35SB120 Fuji Electric 1200V 35A 7-in-1 PIM IGBT Module

Content last revised on February 10, 2026

7MBR35SB120 Fuji Electric IGBT Module: An Engineer's Analysis

Optimized for Efficiency and Power Density in Compact Drive Systems

The 7MBR35SB120 from Fuji Electric is a highly integrated 7-in-1 Power Integrated Module (PIM) engineered to streamline the design of low-to-medium power motion control systems. With core specifications of 1200V and 35A, this IGBT module consolidates critical power stages into a single, compact package, addressing the persistent demand for higher power density and simplified assembly. Key engineering benefits include significantly reduced conduction losses and enhanced thermal performance, stemming from its low VCE(sat) characteristic. By integrating a three-phase converter, brake chopper, and three-phase inverter, the module directly solves the challenge of minimizing footprint in space-constrained applications. For compact motor drives up to 7.5kW requiring an optimal balance of efficiency and a reduced bill of materials, this 35A PIM is an exemplary engineered solution.

Application Scenarios & Value

Achieving System-Level Benefits in Compact Motor Drives

For an engineer designing a servo drive for an automated packaging line, cabinet space and thermal load are primary constraints. The 7MBR35SB120 is purpose-built for these environments. Its primary value lies in its 7-in-1 PIM configuration, which combines a three-phase diode rectifier, a brake chopper, and a full IGBT inverter bridge into one component. This high level of integration dramatically reduces the PCB area required compared to a discrete or multi-module solution, simplifies wiring, and minimizes parasitic inductance, which can improve overall system reliability. Applications such as Variable Frequency Drives (VFDs) for conveyor systems, AC and DC servo drive amplifiers, and small-scale Uninterruptible Power Supplies (UPS) benefit directly from this streamlined design approach, enabling faster assembly and a lower total cost of ownership. For applications demanding a higher current capacity within a similar topology, the related 7MBR50SB120 offers an increased rating of 50A.

Key Parameter Overview

Decoding the Specs for High-Efficiency Power Conversion

The electrical characteristics of the 7MBR35SB120 are optimized for efficient and robust performance in motor drive applications. The low Collector-Emitter Saturation Voltage (VCE(sat)) is a standout feature, directly minimizing power lost as heat during operation. This not only boosts overall efficiency but also simplifies thermal management, potentially allowing for smaller heatsinks. The module's robust short-circuit withstand time provides a critical safety margin, protecting the device during fault conditions common in industrial settings.

Download the 7MBR35SB120 datasheet for detailed specifications and performance curves.

Technical Deep Dive

A Closer Look at the 7-in-1 PIM Architecture

The architectural advantage of the 7MBR35SB120 is its Power Integrated Module (PIM) design, a key technology for achieving high power density. This module integrates three distinct power electronics functions: a three-phase uncontrolled rectifier for AC-DC conversion, a brake chopper (IGBT with a parallel freewheeling diode) for dissipating regenerative energy from the motor, and a three-phase IGBT inverter for DC-AC power conversion to drive the motor. Understanding the module's thermal resistance (Rth) is crucial for reliable design. Think of thermal resistance like the thickness of insulation on a water pipe. A low Rth value means heat can escape easily from the silicon chip to the heatsink, keeping the junction temperature low. The efficient thermal path engineered into this module is fundamental to its long-term reliability, especially in systems with high duty cycles. For a deeper understanding of this topic, exploring resources on IGBT thermal management can provide valuable context.

Frequently Asked Questions (FAQ)

What are the main advantages of the 7-in-1 PIM configuration in the 7MBR35SB120?
The integrated 7-in-1 design significantly reduces system complexity by combining the input rectifier, brake chopper, and output inverter into a single package. This leads to a smaller PCB footprint, simplified assembly and wiring, lower parasitic inductance, and often a lower total system cost.

How does the low VCE(sat) of this IGBT module contribute to system efficiency?
VCE(sat) is the on-state voltage drop across the IGBT. A lower VCE(sat) means lower conduction power losses (P_loss = VCE(sat) * Ic). This directly translates to higher energy efficiency and less waste heat generation, which simplifies the requirements for the cooling system.

What is the primary function of the integrated brake chopper?
The brake chopper circuit is designed to manage regenerative energy. When a motor decelerates, it acts as a generator, sending energy back to the DC bus. The brake chopper diverts this excess energy to an external resistor, preventing the DC bus voltage from rising to dangerous levels and protecting the system.

What is the maximum junction temperature this module can safely operate at?
The 7MBR35SB120 is rated for a maximum operating junction temperature (Tj) of 150°C, providing a solid thermal margin for demanding industrial applications.

From a strategic perspective, the adoption of highly integrated modules like the 7MBR35SB120 is a key enabler for creating more competitive power electronics products. By reducing the bill of materials and simplifying the manufacturing process, it allows engineering teams to shorten design cycles and accelerate time-to-market for next-generation compact drives and power converters. This approach shifts focus from component-level interconnection to system-level optimization, a critical advantage in a fast-moving industrial market. Exploring the trade-offs between integrated and discrete solutions, such as in this IPM vs. Discrete IGBT framework, can further inform design strategy.