Infineon Technologies D911SH45T

Overview

D911SH45T from Infineon Technologies is a press-pack, stud-mounted, fast-recovery high-voltage diode designed for freewheeling and snubber applications in medium-voltage converters. It delivers V_RRM = 4500 V, I_FAVM = 890 A (T_C = 85 °C), I_FSM = 17,000 A, V_T0 = 2.02 V, and r_T = 1.592 mΩ - enabling robust operation in IGCT and IGBT-based traction and industrial drive inverters.

For engineers reviewing the D911SH45T datasheet, D911SH45T pinout, D911SH45T application, or D911SH45T equivalent, key selection criteria include its 45 kN clamping force requirement, two-sided cooling capability, soft turn-off behavior at di/dt up to 1000 A/µs, and 140 °C maximum junction temperature rating.

Technical Context

This device is a silicon-based, pressure-contact, uncontrolled power diode with no gate control or integrated circuitry. Its fast recovery (Q_r ≤ 2.8 mAs, I_RM ≤ 1200 A) and soft reverse recovery (FRRS = 2.5) are achieved via lifetime-controlled base region doping and optimized carrier lifetime termination.

Thermally, it features dual-sided heat dissipation with R_thJC = 10 K/kW (two-sided, DC), supported by a 62.8 mm contact diameter and 100 mm max outer diameter. Mechanical mounting requires controlled clamping force between 27–45 kN to ensure stable thermal and electrical contact integrity.

Key Specifications

Pinout & Package

Package: Press-pack, double-side cooled, stud-mount diode with isolated anode and cathode terminals. Requires mechanical clamping (27–45 kN) onto copper heatsinks with flatness ≤ 0.05 mm and surface roughness ≤ 1.6 µm Ra.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage freewheeling diode applications.

Compared with MDD950-45 and CM600DY-45, D911SH45T offers superior thermal resistance (10 vs. 14.5/22 K/kW), higher surge tolerance (17 kA vs. 15.5/12.5 kA), and press-pack field-replaceability - making it optimal for mission-critical MV drive rebuilds and custom heatsink integration.

Availability

D911SH45T is available at Aetrix Electronics and suitable for medium-voltage converters, IGCT/IGBT freewheeling paths, and pulsed power systems requiring stable component supply across extended production lifecycles.

Supply support for D911SH45T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Infineon Technologies is a German semiconductor manufacturer specializing in power semiconductors, microcontrollers, and security solutions for industrial, automotive, and energy infrastructure markets.

D911SH45T belongs to Infineon's "Fast Hard Drive Diode" product line, engineered specifically for high-reliability, high-current freewheeling and snubber functions in medium-voltage power conversion systems.

FAQ

What is the required clamping force for D911SH45T installation?

The D911SH45T requires a controlled mechanical clamping force between 27 kN and 45 kN to ensure optimal thermal contact and electrical conductivity across both anode and cathode interfaces. Under-torque risks thermal runaway; over-torque may deform the copper contacts or damage internal Si pellet bonding. Use calibrated hydraulic tools and follow Infineon's mounting procedure in Application Note AN2015-01.

Can D911SH45T be used with single-sided cooling?

Yes, but with significant thermal derating: R_thJC rises to 23.6 K/kW (cathode-side only) or 17.4 K/kW (anode-side only), reducing I_FAVM by ~40% at T_C = 85 °C. Dual-sided cooling is strongly recommended to achieve rated 890 A performance and maintain junction temperature below 140 °C under continuous load.

What is the maximum allowable reverse recovery di/dt for reliable operation?

D911SH45T is characterized up to –di/dt = 1000 A/µs with clamp circuit (LS ≤ 0.25 µH, RCL = 68 Ω, CCL = 3 µF). At this rate, peak reverse recovery current I_RM remains ≤ 1200 A and recovered charge Q_r ≤ 2.8 mAs. Exceeding 1000 A/µs risks excessive voltage overshoot and localized heating, especially above 125 °C junction temperature.

Does D911SH45T have a built-in temperature sensor?

No, D911SH45T is a passive, two-terminal power diode with no integrated sensing elements. Thermal monitoring must be implemented externally using thermistors or RTDs mounted on the heatsink near the anode/cathode interfaces, or via infrared imaging aligned to the 62.8 mm contact area per Infineon's thermal design guidelines.