Infineon Technologies TD425N18KOFXPSA1

Overview

TD425N18KOFXPSA1 from Infineon Technologies is a phase-control thyristor module designed for high-power AC line switching and rectification in industrial power electronics. It features 1800 V repetitive peak off-state voltage (VDRM/VRRM), 471 A average on-state current at TC = 85 °C, 14.5 kA non-repetitive surge current (ITSM), and electrically insulated baseplate construction for safe integration into mains-connected systems such as soft starters and UPS rectifiers.

For engineers reviewing the TD425N18KOFXPSA1 datasheet, TD425N18KOFXPSA1 pinout, TD425N18KOFXPSA1 application, or TD425N18KOFXPSA1 equivalent, key selection criteria include junction-to-case thermal resistance (0.065 K/W), gate trigger current (≤250 mA), critical dv/dt rating (1000 V/µs), and pressure-contact die attachment for high-cycle reliability in crowbar and static switch designs.

Technical Context

This dual-thyristor module implements a press-pack, double-sided cooled topology with isolated copper baseplate and AlN ceramic insulation (Class I, IEC 61140). Its 180° conduction capability supports full-wave phase-controlled rectification and bidirectional AC power control in B2 and B6 bridge configurations.

The device operates with gate-controlled turn-on only; it lacks self-commutation and requires external commutation circuitry or forced commutation for turn-off. Critical design parameters include 250 µs typical circuit commutated turn-off time (tq), 120 A/µs critical di/dt, and 0.9 V threshold voltage (VT0) defining minimum gate drive energy requirements.

Key Specifications

Pinout & Package

TD425N18KOFXPSA1 is housed in an industrial-standard press-pack module with electrically insulated baseplate (AlN ceramic), rated for 3.6 kV insulation test voltage (1 sec, 50 Hz). Mechanical mounting uses M1 screws (6 Nm torque); electrical terminals use M2 screws (12 Nm torque) with DIN 46244 A 2.8 × 0.8 mm flat contacts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar phase-control thyristor module applications.

Compared with TT425N18KOFXPSA1, TD425N18KOFXPSA1 provides integrated AlN insulation enabling safer grounded-heatsink mounting, while TD500N18KOFXPSA1 trades baseplate isolation for higher current rating-making the choice dependent on thermal budget versus isolation architecture.

Availability

TD425N18KOFXPSA1 is available at Aetrix Electronics and suitable for soft starters, UPS rectifiers, crowbar protection circuits, and static switches requiring stable component supply and long-term industrial lifecycle support.

Supply support for TD425N18KOFXPSA1 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 sensor solutions for industrial, automotive, and energy applications.

This part belongs to Infineon's Thyristor Module product line, engineered for high-reliability, medium-to-high power AC control in harsh industrial environments including motor drives, power conditioning, and grid-tied equipment.

FAQ

What is the maximum allowable case temperature for continuous operation?

The maximum allowable case temperature (TC) is +125 °C, as specified in the thermal characteristics table. However, the rated average on-state current (ITAVM = 471 A) is defined at TC = 85 °C. Operation above 85 °C requires derating per the ITAVM vs. TC curve on page 7 of the technical information document, with full rating maintained only up to 85 °C under specified conduction angle and cooling conditions.

Does TD425N18KOFXPSA1 support forced commutation?

No, TD425N18KOFXPSA1 is a semi-controlled device that conducts when gated on but cannot be turned off by gate signal alone. Forced or circuit commutation is required to interrupt current flow, as confirmed by its 250 µs typical circuit commutated turn-off time (tq) and absence of gate turn-off capability in all electrical and functional specifications.

What gate drive voltage and current are required for reliable triggering?

A minimum gate trigger voltage of 1.5 V and peak gate trigger current of 250 mA are required at Tj = 25 °C and VD = 12 V, per the datasheet's VGT and IGT maximum ratings. Gate pulse width must exceed 20 µs (latching current condition), and peak gate power must stay within limits shown in Figure 6 (e.g., 100 W for 0.5 ms pulses).

Can this module be used in single-phase applications?

Yes, TD425N18KOFXPSA1 supports single-phase operation in B2 (two-pulse) bridge configurations, delivering up to 1200 A peak output current at TA = 25 °C with RthCA = 0.06 K/W, as shown in Figure 8. Its dual-arm structure allows flexible implementation in both single-phase and three-phase topologies without modification.