Content last revised on November 21, 2025
FRS300BA50 SanRex 500V 300A Fast Recovery Diode Module
Product Overview
High-Speed Switching for Demanding Power Conversion Systems
The SanRex FRS300BA50 is a high-speed, isolated fast recovery diode (FRD) module engineered for high-frequency power systems where efficiency and speed are paramount. It delivers minimal switching and conduction losses through its optimized electrical characteristics. What is the primary benefit of a 200ns trr? Reduced switching losses in high-frequency applications. This module provides a robust solution for engineers designing next-generation power electronics.
- Core Specifications: 500V | 300A | trr ≤ 200ns
- Key Benefits: Enables high-frequency operation; minimizes overall power loss.
Engineered for applications like a fast recovery diode for 300A welding inverters, this module combines a rapid reverse recovery time with a low forward voltage drop to maximize system performance. For high-frequency welding power supplies demanding rapid switching and low losses, the FRS300BA50 is the optimal output rectifier.
Key Parameter Overview
Decoding the Specs for High-Frequency Efficiency
The technical specifications of the FRS300BA50 are tailored for high-reliability, high-frequency applications. The parameters are functionally grouped below to facilitate engineering evaluation for specific performance goals like thermal management and loss reduction.
| Parameter | Symbol | Condition | Max Value | Unit |
|---|---|---|---|---|
| Absolute Maximum Ratings (Tj=25°C) | ||||
| Repetitive Peak Reverse Voltage | VRRM | - | 500 | V |
| Average Forward Current | IF(AV) | Tc=85°C | 300 | A |
| Surge Forward Current | IFSM | 1/2 cycle, 60Hz, non-repetitive | 4000 | A |
| Operating Junction Temperature | Tj | - | -40 to +150 | °C |
| Electrical & Thermal Characteristics | ||||
| Forward Voltage Drop | VFM | IFM=300A, Tj=25°C | 1.3 | V |
| Reverse Recovery Time | trr | IF=300A, -di/dt=300A/µs | 200 | ns |
| Repetitive Peak Reverse Current | IRRM | VRRM=500V, Tj=125°C | 300 | mA |
| Thermal Impedance | Rth(j-c) | Junction to Case | 0.165 | °C/W |
Download the FRS300BA50 datasheet for detailed specifications and performance curves.
Application Scenarios & Value
Achieving System-Level Benefits in High-Frequency Power Supplies
The FRS300BA50 is ideally suited for the output rectifier stage of high-frequency power conversion systems where minimizing power loss is a critical design objective. Its characteristics directly translate into tangible system-level advantages.
Consider the design of a high-power inverter welding power supply. In this environment, the diode must switch rapidly to handle the high-frequency output of the inverter stage. The FRS300BA50's maximum reverse recovery time (trr) of 200ns is crucial. A slower diode would allow a brief but significant reverse current to flow during each switching cycle, generating substantial switching losses as heat. The fast recovery of the FRS300BA50 curtails this reverse current, directly improving efficiency, reducing heatsink requirements, and enabling a more compact and reliable end product. For systems operating at different voltage and current levels, the DF200BA80 offers an 800V, 200A alternative.
Frequently Asked Questions (FAQ)
Engineering Insights into the FRS300BA50
How does the reverse recovery time (trr) of 200ns impact my design choices?
A sub-200ns trr allows you to confidently operate at higher switching frequencies (e.g., >50 kHz) without incurring excessive switching losses. This enables the use of smaller, lighter, and more cost-effective magnetic components, such as transformers and inductors, which is a key factor in increasing the power density of a Switched-Mode Power Supply (SMPS) or inverter. Further insights can be found in resources covering Switching Loss phenomena.
What is the significance of the 4000A surge current rating (IFSM)?
The 4000A IFSM rating provides a substantial safety margin against fault conditions. In applications like welding or motor drives, transient events such as inrush currents can expose components to currents far exceeding their nominal ratings. This high surge capability ensures the diode can withstand such events without failure, a critical aspect for long-term system reliability. For more on preventing component failure, see our guide on IGBT failure analysis.
Technical Deep Dive
A Closer Look at the Interplay of VFM and trr for Optimal Efficiency
The core value of the FRS300BA50 lies in its dual optimization of both major power loss contributors in a diode: conduction and switching losses. The maximum forward voltage (VFM) of 1.3V at the full 300A rating directly governs conduction loss. This low VFM means less energy is converted into waste heat while the diode is actively conducting current, a critical factor for overall system efficiency, especially in applications with high duty cycles.
Simultaneously, the fast reverse recovery time (trr) attacks the other side of the efficiency equation—switching loss. Think of the `trr` like the closing speed of a high-pressure water valve. A slow-closing valve allows a significant amount of water to splash back (reverse current) before sealing shut, wasting energy. The FRS300BA50's 200ns `trr` acts like a valve that snaps shut almost instantly, minimizing this wasteful "splash" and the associated energy loss during each off-transition. This synergy makes the device a prime candidate for modern high-frequency welding equipment and telecom power supplies built around efficiency and power density targets.
For engineering teams evaluating the FRS300BA50 for new designs, detailed thermal modeling is recommended. Please refer to the full datasheet to ensure optimal performance and long-term reliability in your specific application.
