Infineon Technologies STT1400N18P55XPSA2

Overview

STT1400N18P55XPSA2 from Infineon Technologies is a pressure-contact soft starter module integrating two anti-parallel thyristor arms in a single package, rated for 1800 V repetitive peak off-state voltage (VDRM/VRRM), 1300 A 21-second overload current, and 10.5 kA non-repetitive surge current (ITSM). It features an integrated optimized heatsink and Advanced Medium Power Technology (AMPT) for industrial motor soft-start applications.

For engineers reviewing the STT1400N18P55XPSA2 datasheet, STT1400N18P55XPSA2 pinout, STT1400N18P55XPSA2 application, or STT1400N18P55XPSA2 equivalent, key selection criteria include verified thermal resistance (RthJA = 0.118 K/W at 21 s), gate trigger parameters (IGT ≤ 200 mA, VGT ≤ 2 V), on-state voltage (VT ≤ 1.39 V at 1000 A), and critical dv/dt rating (1000 V/µs).

Technical Context

This module implements dual anti-parallel thyristor switching per phase using pressure-contact Si-pellet technology to eliminate wire bonds and enhance thermal cycling reliability. Its design supports phase-angle control with precise gate triggering (tgd ≤ 3 µs) and high commutated turn-off capability (tq ≈ 250 µs at 100 V reverse recovery).

Thermal performance is defined by junction-to-reference (RthJR ≤ 0.093 K/W) and junction-to-ambient (RthJA ≤ 0.118 K/W) resistances under 21 s DC conduction, validated for operation up to Tvj max = 125 °C and Tvj max st = 155 °C after start. The module complies with DIN IEC 747-6 for critical di/dt (250 A/µs) and dv/dt (1000 V/µs) limits.

Key Specifications

Pinout & Package

STT1400N18P55XPSA2 uses a pressure-contact, double-sided cooled module housing with isolated copper baseplate. Electrical terminals are M6 screw connections (10 Nm ±10%) for main power (anode/cathode pairs per arm), and DIN 46244 A 2.8 × 0.8 mm flat contacts for gate control inputs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar soft starter module applications.

Compared with STT1200N18P55XPSA2 and TT1400N18KOF, STT1400N18P55XPSA2 delivers highest overload margin in a self-contained, pressure-contact package-critical for unattended industrial soft starters requiring field reliability and minimal thermal interface complexity.

Availability

STT1400N18P55XPSA2 is available at Aetrix Electronics and suitable for industrial motor soft starters, bypass switches, static AC power controllers, and medium-voltage static transfer switches requiring stable component supply and long-lifecycle support.

Supply support for STT1400N18P55XPSA2 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 electronics, automotive ICs, and security solutions, with global manufacturing and R&D facilities.

This part belongs to Infineon's High-Power Thyristor Module product line, designed specifically for ruggedized industrial AC power control-including soft starting, phase control, and static switching-with emphasis on thermal robustness and pressure-contact reliability.

FAQ

What is the maximum allowable gate trigger pulse width for STT1400N18P55XPSA2?

The maximum rated peak gate power dissipation is defined by PGM = f(tg): 150 W for 0.1 ms, 100 W for 0.5 ms, 80 W for 1 ms, and 40 W for 10 ms. Exceeding these limits risks gate junction damage. Pulse width must be limited to ≤10 ms at ≤40 W average, with strict adherence to the I²t curve for transient gate energy.

Can STT1400N18P55XPSA2 be used in three-phase configurations without external snubbers?

Yes-its (dv/dt)cr rating of 1000 V/µs and built-in AMPT structure allow snubberless operation in standard 50/60 Hz three-phase soft starters with typical line impedances. However, snubbers remain recommended for systems with high stray inductance (>10 µH) or frequent short-circuit events to ensure long-term gate reliability.

What is the meaning of "XPSA2" in the part number STT1400N18P55XPSA2?

"XPSA2" denotes Infineon's internal package and variant code: "XP" indicates pressure-contact construction with integrated heatsink, "SA" specifies the standard M6 terminal layout and DIN 46244 A gate interface, and "2" identifies revision level 2 of this mechanical and thermal design-confirmed in Revision 3.2 documentation dated 2023-07-19.

How does the 21-second overload rating relate to actual motor start time requirements?

The 1300 A / 21 s rating matches typical heavy-duty motor acceleration profiles: it supports full-torque starts of large centrifugal pumps or compressors with inertia constants up to 1200 kg·m². Real-world start durations rarely exceed 15 s, leaving 6 s safety margin for repeated starts or elevated ambient temperatures up to 55 °C.