Infineon IPB65R050CFD7AATMA1 650V CoolMOS™ CFD7 Power Transistor: Datasheet, Application Circuit, and Design Considerations

The relentless pursuit of higher efficiency, power density, and reliability in power electronics has driven the evolution of MOSFET technology. At the forefront of this innovation is Infineon's CoolMOS™ CFD7 series, with the IPB65R050CFD7AATMA1 standing out as a premier 650V superjunction (SJ) MOSFET engineered for demanding applications. This article delves into its key specifications, a typical application circuit, and crucial design considerations.

Datasheet Deep Dive: Unpacking Key Specifications

The datasheet for the IPB65R050CFD7AATMA1 reveals a component optimized for high-performance switching. The "050" in its name signifies an ultra-low typical on-state resistance (RDS(on)) of just 50 mΩ at a gate-source voltage (VGS) of 10 V. This low resistance is the primary contributor to minimizing conduction losses, a critical factor for efficiency.

A hallmark of the CFD7 family is its integrated fast body diode. Unlike traditional SJ MOSFETs, this feature eliminates the poor reverse recovery characteristics typically associated with an external body diode. The diode boasts a soft reverse recovery behavior and a low reverse recovery charge (Qrr), which drastically reduces switching losses and electromagnetic interference (EMI). This makes it exceptionally suitable for topologies like Power Factor Correction (PFC) and hard-switching bridges where the body diode conducts.

Other vital parameters from the datasheet include:

High Voltage Rating: 650 V, offering robust margin for off-line applications (e.g., 230 VAC mains).

Low Gate Charge (Qg): Ensures low driving losses and simplifies gate drive requirements.

Excellent Figure of Merit (FOM): The product of RDS(on) and Qg is exceptionally low, indicating a superior balance between conduction and switching performance.

Application Circuit: A Look at a High-Efficiency PFC Stage

A quintessential application for the IPB65R050CFD7AATMA1 is in a continuous conduction mode (CCM) boost PFC circuit. This stage is critical in modern switched-mode power supplies (SMPS) to achieve a high power factor and comply with harmonic current regulations.

In this circuit, the MOSFET acts as the main switch. The driver IC, controlled by a PFC controller, provides the gate signal. The key advantage of using the CFD7 here is its integrated fast body diode. During the dead time in the switching cycle, when the inductor current freewheels through the MOSFET's body diode, the soft recovery characteristic minimizes voltage spikes and ringing across the switch. This leads to:

Reduced stress on the MOSFET itself.

Lower EMI filtering requirements.

Higher overall efficiency at high switching frequencies.

The low RDS(on) directly cuts down I²R losses, allowing for a more compact thermal design or higher power output from a similarly sized system.

Critical Design Considerations

1. Gate Driving: While the Qg is low, a proper gate driver is essential. A driver with a peak current capability of several amperes is recommended to quickly turn the device on and off, minimizing transition times through the Miller plateau and further reducing switching losses.

2. PCB Layout: The high switching speed (dv/dt and di/dt) of the CoolMOS™ CFD7 demands a careful PCB layout. The gate drive loop and the power loop must be as small and tight as possible to minimize parasitic inductance. Stray inductance can cause severe ringing, overshoot, and potential false triggering or device destruction.

3. Thermal Management: Despite its high efficiency, heat must be effectively managed. The IPB65R050CFD7AATMA1 comes in a TOLL (TO-leadless) package, which offers excellent thermal performance due to its large exposed top pad. Adequate heatsinking is mandatory, and thermal vias should be used to transfer heat to the opposite side of the PCB.

4. Avalanche Ruggedness: While robust, it is always preferable to operate the MOSFET within its specified Safe Operating Area (SOA). Design the circuit to avoid unclamped inductive switching events unless the specific avalanche energy ratings have been consulted.

ICGOOODFIND Summary

The Infineon IPB65R050CFD7AATMA1 CoolMOS™ CFD7 represents a significant leap in high-voltage power switch technology. Its combination of ultra-low on-resistance, an integrated fast body diode, and an advanced package makes it an ideal choice for engineers aiming to push the boundaries of efficiency and power density in applications like server and telecom SMPS, industrial drives, solar inverters, and EV charging infrastructure. Successful implementation hinges on a thoughtful design approach, particularly concerning the gate drive and PCB layout, to fully leverage its superior performance characteristics.

Keywords:

CoolMOS™ CFD7

Ultra-Low RDS(on)

Integrated Fast Body Diode

Application Circuit

Design Considerations