TOSHIBA MG Series IGBT Power Modules: MG50Q2YS91

Technical Dossier

Product Details And Specifications

TOSHIBA MG Series IGBT Power Modules: Comprehensive Module Range and Technical Overview

The TOSHIBA MG Series represents one of the most widely deployed families of IGBT (Insulated Gate Bipolar Transistor) power modules in global heavy industry. Installed across chemical processing plants, nuclear power auxiliary systems, petroleum refinery drive systems, steel mill variable frequency drives, and large-scale UPS infrastructure, the MG Series established TOSHIBA as a tier-one supplier of discrete power semiconductor modules throughout the 1990s and 2000s. These modules are characterized by their dual, single, and six-pack IGBT configurations, rated from 25A to 600A collector current and blocking voltages from 600V to 1200V (VCES). The MG50Q2YS91 is a representative dual IGBT module rated at 50A / 1200V, widely used in medium-power inverter and chopper circuits.

The Evolution of MG Series Architecture

The TOSHIBA MG Series was introduced in the late 1980s as a response to industrial demand for compact, high-reliability IGBT modules that could replace older Darlington transistor assemblies. Early generations (MG Series Gen 1, circa 1988–1993) used aluminum wire bonding on standard DBC (Direct Bonded Copper) substrates with relatively high switching losses, suitable for carrier frequencies below 5 kHz. The second generation (Gen 2, 1993–2000) introduced improved gate oxide technology, reducing VCE(sat) and enabling operation at 8–10 kHz in motor drive applications. The third generation (Gen 3, 2000–2008) incorporated trench-gate IGBT cell structures, significantly improving conduction efficiency and thermal cycling endurance — critical for continuous-duty industrial drives.

Compatibility across generations is constrained by pinout and package format. The TO-247, TO-3P, and proprietary flat-base module packages used across the MG Series are not interchangeable without PCB or busbar redesign. Engineers maintaining legacy equipment must verify the exact package code suffix (e.g., YS91, YS40) before substitution. TOSHIBA officially discontinued active production of most MG Series variants by 2015, transitioning customers to the GT Series (e.g., GT50J325) and MG-G Series with improved short-circuit withstand capability. However, installed base demand for MG Series modules in legacy drives remains substantial, making aftermarket sourcing a critical operational requirement.

MG Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly referenced models within the TOSHIBA MG Series. Each entry includes the primary functional classification and key electrical parameter.

MG50Q2YS91: Dual IGBT module, 50A / 1200V, flat-base package, inverter/chopper use.
MG75Q2YS91: Dual IGBT module, 75A / 1200V, flat-base package, medium-power drive stages.
MG100Q2YS91: Dual IGBT module, 100A / 1200V, high-current inverter half-bridge configuration.
MG150Q2YS91: Dual IGBT module, 150A / 1200V, heavy-duty drive and traction inverter use.
MG200Q2YS91: Dual IGBT module, 200A / 1200V, large industrial inverter output stage.
MG25Q6ES51: Six-pack IGBT module, 25A / 600V, compact three-phase inverter bridge.
MG50Q6ES51: Six-pack IGBT module, 50A / 600V, three-phase motor drive full-bridge.
MG75Q6ES51: Six-pack IGBT module, 75A / 600V, HVAC and pump drive inverter bridge.
MG100Q6ES51: Six-pack IGBT module, 100A / 600V, industrial servo and spindle drive.
MG150Q6ES51: Six-pack IGBT module, 150A / 600V, high-power three-phase inverter stage.
MG50J6ES51: Six-pack IGBT module, 50A / 600V, J-series gate structure, lower switching loss.
MG75J6ES51: Six-pack IGBT module, 75A / 600V, J-series, improved thermal resistance.
MG100J6ES51: Six-pack IGBT module, 100A / 600V, J-series, enhanced short-circuit rating.
MG300Q1US51: Single IGBT module, 300A / 600V, chopper and DC bus switch applications.
MG400Q1US51: Single IGBT module, 400A / 600V, high-current DC chopper and braking circuits.
MG600Q1US51: Single IGBT module, 600A / 600V, large-scale rectifier and inverter switch.
MG50Q2YS40: Dual IGBT module, 50A / 1200V, YS40 package variant, alternative footprint.
MG75Q2YS40: Dual IGBT module, 75A / 1200V, YS40 package, compatible gate driver interface.

Sourcing Hard-to-Find & Obsolete MG Series Parts

The TOSHIBA MG Series entered end-of-life status progressively between 2010 and 2018. TOSHIBA ceased new production of the majority of MG-suffix IGBT modules, and authorized distribution channels no longer carry active stock for most variants. For operators of legacy variable frequency drives, UPS systems, and industrial inverters built around MG Series modules, unplanned downtime caused by module failure represents a critical operational risk.

DriveKNMS maintains a dedicated inventory program for obsolete and hard-to-find TOSHIBA MG Series modules. Stock is sourced through verified industrial surplus channels, decommissioned equipment recovery, and long-term storage partners. All units are stored in ESD-safe, climate-controlled environments to preserve junction integrity and gate oxide condition. DriveKNMS provides traceability documentation for each unit, including date code, lot identification where available, and pre-shipment test records. For customers requiring long-term maintenance contracts covering MG Series module replenishment across multi-year plant maintenance cycles, DriveKNMS offers reserved stock agreements with defined lead times and pricing structures.

Quality Control for the MG Series Range

IGBT power modules present specific failure modes that require targeted test procedures beyond standard component screening. For the TOSHIBA MG Series, DriveKNMS applies the following verification protocol to all units prior to shipment:

Static Parameter Verification: Each module is tested for VCES (collector-emitter blocking voltage), VGES (gate-emitter voltage), ICES (leakage current at rated VCES), and VCE(sat) at defined IC and VGE conditions. Results are compared against TOSHIBA datasheet limits for the specific part number.
Gate Integrity Test: Gate oxide condition is assessed via gate charge measurement and gate leakage current at ±20V VGE. Degraded gate oxide — a common failure mode in aged or improperly stored modules — is identified and units are rejected.
Thermal Resistance Check: For modules where the thermal interface compound may have degraded, junction-to-case thermal resistance (Rth(j-c)) is verified using a controlled power dissipation and temperature measurement cycle.
Freewheeling Diode Test: The integrated anti-parallel diodes in each IGBT cell are tested for forward voltage drop (VF) and reverse leakage to confirm co-pack diode integrity.
Visual and Mechanical Inspection: Substrate crack detection, terminal corrosion assessment, and encapsulant condition review are performed under magnification before packaging.

For sourcing inquiries, technical specifications, or long-term supply agreements for TOSHIBA MG Series IGBT modules: