Content last revised on February 6, 2026
7MBR35SB120-01: Engineering an Integrated Power Core for Compact Motor Drives
The Fuji Electric 7MBR35SB120-01 is a 7-in-1 Power Integrated Module (PIM) designed to streamline the architecture of low-to-medium power motion control systems. It integrates a three-phase converter and inverter, a brake chopper, and an NTC thermistor into a single compact package, offering key specifications of 1200V and 35A. This level of integration directly addresses the engineering challenge of reducing system size and assembly complexity. The module is engineered for applications where board space, thermal management, and reliability are critical design drivers. For applications requiring higher current capacity within a similar integrated framework, the 7MBR50SB120 offers an increased rating of 50A.
Key Parameter Overview
Decoding the Specs for Integrated Power Stage Design
The technical specifications of the 7MBR35SB120-01 are optimized for efficiency and reliability in motor control and power conversion applications. The low collector-emitter saturation voltage (VCE(sat)) is a critical parameter that directly minimizes conduction losses, which is paramount for overall system efficiency. The integration of a full converter bridge, a three-phase inverter, and a dynamic brake circuit into one module simplifies design, reduces component count, and minimizes parasitic inductance, leading to improved electrical performance.
| Parameter | Value | Conditions |
|---|---|---|
| Collector-Emitter Voltage (VCES) | 1200V | - |
| Inverter Collector Current (IC) | 35A | TC = 80°C |
| Brake Chopper Collector Current (IC) | 25A | TC = 80°C |
| Collector-Emitter Saturation Voltage (VCE(sat)) | 2.2V (typ), 2.7V (max) | IC = 35A, VGE = 15V, Tj = 25°C |
| Power Dissipation (PC) - Inverter | 240W | 1 device |
| Isolation Voltage (Viso) | AC 2500V | 1 minute |
Download the 7MBR35SB120-01 datasheet for detailed specifications and performance curves.
Application Scenarios & Value
Achieving System-Level Benefits in Compact Motion Control
The 7MBR35SB120-01 is best suited for low-to-medium power applications where a high degree of integration translates directly into smaller, more reliable, and cost-effective systems. For designers of compact AC servo drives, this module provides a significant advantage.
A key engineering challenge in servo drive design is managing the power density and thermal footprint within a constrained enclosure. The traditional approach requires separate components for the input rectifier, the inverter stage, and the brake chopper, increasing PCB complexity and assembly time. The 7MBR35SB120-01 consolidates these core functions into a single PIM package. This consolidation acts like a multi-tool for power electronics, providing the essential functions in one device. This not only saves valuable board space but also reduces the number of interconnects, which in turn lowers stray inductance and potential EMI issues—a crucial factor for achieving precision in robotic servo drives. The module's **1200V** rating provides substantial voltage headroom for drives operating on 380-480V AC lines, ensuring robust performance against voltage transients.
Its capabilities are particularly valuable in:
- AC and DC Servo Drive Amplifiers: Where precise control and compact form factor are essential for robotics and CNC machinery.
- General-Purpose Inverters: For controlling small industrial motors in applications like conveyor systems, fans, and pumps.
- Uninterruptible Power Supplies (UPS): Providing a reliable and compact power conversion stage.
Application Vignette
Designing a 5kW Servo Drive with Integrated Braking
Consider the design of a compact 5kW servo drive for an automated assembly line. The primary constraints are size, thermal efficiency, and minimizing assembly costs. Using discrete components would require designing separate circuits for rectification, inversion, and dynamic braking, leading to a larger PCB and complex thermal management.
The 7MBR35SB120-01 provides an elegant solution. Its integrated three-phase diode bridge rectifies the AC input. The 35A, 1200V inverter stage efficiently drives the motor. During deceleration, the motor acts as a generator, causing the DC bus voltage to rise. The integrated 25A brake chopper safely dissipates this regenerative energy through an external resistor, protecting the system. This entire power-handling process is managed within a single module. The built-in NTC thermistor allows the system controller to monitor the module's temperature in real-time, enabling active thermal management and enhancing long-term reliability. This high level of integration dramatically simplifies the power stage design, allowing engineers to focus on control logic and software, ultimately accelerating time-to-market. The module's performance is underpinned by robust Fuji Electric power module technology, ensuring reliability in demanding industrial environments.
Frequently Asked Questions (FAQ)
How does the 7-in-1 integration of the 7MBR35SB120-01 benefit my design compared to using discrete components?
The primary benefits are significant space savings on the PCB, reduced assembly complexity and cost, and improved electrical performance. By integrating the rectifier, inverter, and brake chopper, the module minimizes stray inductance between stages, which can reduce voltage overshoots and improve overall system reliability.
What is the role of the integrated brake chopper circuit?
The brake chopper is essential for managing regenerative energy in motor drive applications. When a motor decelerates, it acts as a generator and sends energy back to the DC bus, causing the voltage to increase. The brake chopper diverts this excess energy to an external resistor, preventing the DC bus voltage from exceeding safe limits and protecting the system from damage.
What are the considerations for thermal management with this PIM?
While the module is designed for low power loss, effective thermal management is crucial for reliability. The baseplate must be mounted to an appropriately sized heatsink with a thermal interface material to ensure a low thermal resistance path. The integrated NTC thermistor should be used to monitor the module's temperature, allowing the system to implement fault protection or derating strategies if temperatures exceed operational limits. A comprehensive guide to IGBT thermal management can provide further insights.
The strategic value of the 7MBR35SB120-01 lies in its ability to abstract away the complexity of power stage hardware design. For engineering teams focused on rapid development and system-level innovation, this module provides a validated, reliable power core, enabling them to deliver more compact and cost-effective motion control solutions to the market faster.
