Le blog de l'entreprise Infineon IMDQ75R High Robust 750V CoolSiC™ MOSFET Transistor For AI Server Applications

Shenzhen Mingjiada Electronics Co., Ltd. supplies and recycles Infineon’s IMDQ75R series of high-reliability 750V CoolSiC™ MOSFETs, suitable for artificial intelligence server applications.

I. Overview of the IMDQ75R Series

The IMDQ75R series comprises Infineon’s second-generation CoolSiC™ G2 trench-type silicon carbide MOSFETs. These 750V industrial-grade SMD surface-mount power devices utilise the Q‑DPAK top-cooled package and are designed for high-density switching power supplies (PSUs), totem-pole PFCs, LLC resonant converters and intermediate bus converters (IBCs), addressing the design challenges associated with high power, high current, high-frequency operation, stringent thermal management and long-term uninterrupted operation in AI servers. The devices have fully passed JEDEC industrial reliability testing and 100% avalanche breakdown voltage verification, delivering high efficiency, high power density and long-term operational reliability under continuous, heavy-load conditions in data centres operating 24 hours a day, 7 days a week.

Key Parameter Summary

- Drain-source breakdown voltage V₍DSS₎: 750 V

- On-resistance RDS (on): typical 25 mΩ, maximum 31 mΩ @ Tj = 25 °C

- Pulse drain current I (D,pulse): 242 A

- Gate charge Q₍G₎: 49 nC

- Energy stored in output capacitance under 500 V conditions E₍OSS₎: 18.5 μJ

- Package: Q‑DPAK (PG‑HDSOP‑22) surface-mount, top-cooled

- Operating junction temperature: –55 °C to 175 °C

II. Core Electrical and Packaging Parameters of the IMDQ75R Series

1. Electrical Withstand Voltage and Avalanche Reliability

Drain–source rated voltage of **750 V**, maintained across the entire junction temperature range; 100 per cent of devices have undergone avalanche stress testing, demonstrating strong resistance to surges and voltage spikes; Typical gate threshold voltage of 4.5 V, combined with a low Crss/Ciss ratio, significantly mitigates the risk of parasitic conduction in high-speed switching scenarios, making it suitable for the severe electromagnetic interference conditions associated with high-density board layouts in AI server power supplies. Supports a wide range of negative gate drive voltages from –7 V to –11 V, further enhancing the system’s immunity to interference.

2. Excellent Figure of Merit (FOM), reducing overall system losses

Based on the second-generation trench CoolSiC™ process, it achieves an industry-leading `RDS(on)×Qfr`, whilst also offering excellent comprehensive FOM values for `RDS(on)×Qoss` and `RDS(on)×QG`; Output capacitance energy storage (Eoss) and gate charge (Qg) have been significantly optimised. Compared to first-generation products, switching speed has increased by approximately 25%–30%, whilst switching losses have been reduced by over 30%. High-efficiency performance is achieved in both hard-switching and soft-switching topologies, helping AI server power supplies to operate at higher frequencies, reduce the size of magnetic components, and improve overall power density. The device incorporates a high-performance SiC intrinsic diode with extremely low reverse recovery charge, eliminating the need for additional parallel fast-recovery diodes and simplifying the design of power supply peripheral components.

3. Thermal Design and Long-Term Operational Capability

Utilising Infineon’s proprietary .XT diffusion-bonded chip mounting process and a Q-DPAK top-cooled package, the device features a short heat path and excellent thermal resistance. with an operating junction temperature range of –55 °C to 175 °C. It can withstand 24/7 continuous full-load operation under the high ambient temperatures typical of AI server rooms. When multiple devices are connected in parallel, they exhibit excellent current sharing characteristics, meeting the requirements for high-power server power supply expansion designs. The package integrates an independent drive source-side Kelvin pin, separating the power circuit from the drive circuit to reduce parasitic inductance in the circuitry and further improve high-frequency switching stability.

III. Key Technical Characteristics of the IMDQ75R Series

1. Second-generation CoolSiC™ trench SiC process, with a 20–35% improvement in the device’s figure of merit (FOM) compared to the previous generation; industry-leading quality factors for R_DS(on)×Q_oss and R_DS(on)×Q_fr, achieving dual optimisation of on-state and switching losses.

2. High-reliability substrate design, with 100% avalanche testing and screening, and gate oxide reliability rigorously verified; the negative gate tolerance range has been extended to cope with voltage disturbances caused by frequent load transients in AI power supplies and instantaneous peak surges in GPUs, thereby reducing the risk of device failure.

3. Top-cooled Q-DPAK packaging; .XT diffusion bonding technology reduces thermal resistance and enhances heat dissipation efficiency; the SMD form factor facilitates high-density layout on power supply boards, enabling AI server power supplies to achieve ultra-high power density designs of > 100 W/in³ and reducing the overall system footprint.

4. Excellent high-frequency compatibility, with switching losses minimally affected by temperature, enabling a significant increase in PFC and LLC operating frequencies. This reduces the size of magnetic components such as transformers and inductors, thereby lowering the bill of materials for server power supplies and the overall weight of the system.

5. User-friendly parallel operation capability, with independent drive source pins that suppress current imbalance during parallel operation, allowing multiple devices to be easily connected in parallel to meet the output requirements of high-power supply units in AI servers operating at tens of kilowatts.

IV. Value of the IMDQ75R Series for Artificial Intelligence Server Applications

GPU workloads in high-computing-power AI servers are characterised by large transient inrush currents, sustained high loads, elevated cabinet ambient temperatures and year-round uninterrupted operation. Traditional silicon-based MOSFETs and IGBTs suffer from high losses and significant thermal challenges in high-frequency, high-power scenarios, limiting improvements in power supply efficiency and power density.

Suitable for high-density PSU power supply systems in AI computing servers, covering the AC–DC front-end PFC conversion stage, the rear-end LLC resonant DC–DC conversion, and dual active bridge (DAB) power modules in AI servers.

1. Improved power conversion efficiency: Extremely low conduction and switching losses reduce heat generation within the server power supply itself, lower the power consumption of the data centre’s cooling systems, improve PUE metrics, and meet the requirements for continuous high-current output in high-computing-power AI scenarios.

2. Achieves miniaturisation and high power density: Enables the power supply to operate at higher switching frequencies, reducing the size of passive components such as transformers and inductors, and facilitating the evolution of server power supplies towards higher power density and smaller form factors.

3. Enhanced long-term system reliability: 100% avalanche testing, strong resistance to parasitic conduction, and the ability to operate over a wide junction temperature range enable the module to cope with the severe fluctuations in AI server loads and large transient inrush currents, thereby reducing the risk of power supply failure and ensuring the continuous and stable operation of computing workloads.

4. Simplified hardware development: The integrated diode offers excellent reverse recovery characteristics and a driver-friendly design, ensuring compatibility with mature SiC gate driver chips and shortening the development cycle for server power supply projects.

V. Typical Application Scenarios for the IMDQ75R Series

Artificial Intelligence / AI Computing Server Switching Power Supplies (PSUs)

Data Centre High-Voltage Direct Current Intermediate Bus Converters (IBCs)

Totem-Pole PFC and LLC Resonant Power Conversion Topologies

High-End Telecommunications Power Supplies and Uninterruptible Power Supplies (UPS)

Industrial High-Power SMPS Switching Power Supply Systems

VI. Infineon IMDQ75R Series Products:

IMDQ75R011M2H

IMDQ75R020M2H

IMDQ75R033M2H

IMDQ75R040M2H

IMDQ75R050M2H