Fast and accurate thermal test, measurement and characterization of IC packages, LEDs and systems


T3Ster® (pronounced "Tris-ter") is an advanced thermal tester for thermal characterization of IC packages, LEDs and systems producing extensive thermal characteristics rapidly. A proprietary system consisting of software and hardware, T3Ster is designed to meet the needs of the semiconductor, transportation, consumer electronics and LED industries as well as R&D laboratories.


Rapid Thermal Transient Testing of Single and Stacked Die Packages and LEDs

A consistent set of testing hardware and software, T3Ster is aimed at dynamic thermal characterization of packaged semiconductor devices (diodes, BJTs, power MOSFETs, IGBTs, power LEDs), stacked die and other multi-die devices.

With dedicated fixtures and software, characterization of MCPCBs and other substrates or cooling assemblies is also possible. Dedicated test environments added to T3Ster form special solutions aimed at comprehensive testing of LEDs (TeraLED) and thermal interface materials (DynTIM).


Non-destructive Component Failure Analysis

By using T3Ster, semiconductor manufacturers can design chips and ICs of superior thermal performance and publish reliable thermal data for downstream applications while equipment manufacturers can design reliable products and avoid thermally induced failures throughout the product’s lifetime.

Unlike other systems, T3Ster directly measures the actual heating or cooling curves – the thermal transient response of packaged semiconductor devices – rather than artificially composing them from individual responses. T3Ster offers extremely accurate temperature measurements (0.01° C) and 1 micro-second measurement resolution in time.


Reliability Testing with Power Cycling and Subsequent Structure Function Analysis

Die-attach failures are easily located using structure functions. Structure functions show the thermal resistance/capacitance map along the heat flow path in a semiconductor package.

Irregularities in heat removal (as in the case of a faulty die attach) can be easily identified and localized with the help of the resulting diagrams.


This method is an ideal pre- and post-stress failure detection tool in reliability analysis. This laboratory testing method is suitable for power LEDs, IGBTs and stacked die solutions. Add-ons to T3Ster allowing high throughput laboratory testing are also available.


Full Support of the Transient Dual Interface Method (JEDEC JESD51-14 standard) and LED thermal testing (JEDEC JESD51-51, 51-52 standards)

T3Ster implements the latest JEDEC thermal test standards as well as JEDEC compliant thermal resistance measurements and dynamic characterization.

It also fully supports the transient dual interface method (JEDEC JESD51-14 standard, published in 2010) and the latest LED thermal testing standards (JEDEC JESD51-51, 51-52, published in 2012).


Options and Accessories


T3Ster Multi Channel Power Driving Unit

The multichannel power driving module increases the power driver channels of T3Ster equipment from 1 to either 4 or 7 channels.

Housed in the same type of enclosure as the main system, this unit provides additional power switching modules and measurement current sources. The main benefit of having an extension box is to enable measurement setups where multiple junctions need to be driven in order to achieve full thermal characterization of the device under test. These include multi-chip module, stacked-die and other multi-die package applications as well as measurement of power LED assemblies with multiple light sources such as RGB modules.


JEDEC Standard: Still-Air Chamber

To assure a JEDEC JESD51-2 compliant setup for thermal transient measurements in a natural convection environment, Mentor Graphics also offers a still-air chamber (1 ft3). The chamber can be easily adjusted to any JEDEC standard thermal test board size and to any edge connector type.

Keeping all the essential elements of the standard JEDEC test procedures, transient tests allow exploration of all details in the entire junction-to-ambient heat-flow path with the help of structure functions – in addition to offering the standard, single lumped RthJA value it.


T3Ster Thermostat

The Peltier-cell cooled dry thermostat is designed for the calibration of temperature sensing semiconductor structures in the devices being tested. It is controlled by the measurement software and can be used as a single-side cold plate as well. The thermostat module of theT3Ster software provides automatic temperature excursion and calculation of the sensitivity parameter of diode or resistance sensors.

Dual Cold-Plates

Dual cold-plates are standard in the DELPHI methodology to provide hard thermal boundary conditions for the required thermal measurements. Cold-plates are also essential for junction-to-case thermal measurements.

Junction-to-case measurements can be easily realized with the transient test method and the structure functions (see e.g. the JEDEC JESD51-14 standard).


Liquid cooled dual cold-plates can be used in testing of large, high power devices and are also ideal for testing multiple devices at the same time in multi-channel measurement configurations using e.g. different power driving options of T3Ster. Software support is provided for temperature control of Mentor Graphics dual cold-plates. The T3Ster measurement control tool handles a wide range of 3rd party external liquid-based thermostats (such as different models of JULABO).


T3Ster Booster Devices

Boosters raise the power for tests either by extending the heating current or the device voltage range of T3Ster. Up to two boosting channels can be placed into a single (19 inch, 3U high) enclosure.

Because boosters are modular the systems can be easily extended to drive tens and hundreds of Amperes (low voltage family of boosters) or up to 280 V (high voltage boosters).


To measure with really high power, external power supplies are required. Built-in software support of Agilent power supplies is provided. Applications include:


  • measurement of power devices such as power MOSFETs, IGBTs, etc
  • measurement of power LED assemblies and LED lines
  • measurement of large area VLSI chips using the substrate diode


Any number of booster devices can be connected to the system to form a multi-channel high power testing setup used e.g. for reliability testing applications.


Additional Measurement Channels

T3Ster can be equipped with up to 8 measurement channels. Systems with fewer channels can be upgraded any time by simply adding the required number of new channels – recognized by the measurement control software automatically.

Thermocouple Pre-Amplifiers

Thermocouple pre-amplifiers are provided for an easy interfacing of J, K or T type thermocouples to T3Ster. The amplifiers have a cold point compensation and provide an output voltage range matched to the measurement channels of T3Ster. The power supply of the amplifiers is provided from T3Ster through the measurement channel.

MIL-STD 750E Interface

This unit is used in connection with high current T3Ster Booster to serve as constant VCB generator for measurement of BJTs according to MIL-STD 750E.

By using this in connection with the T3Ster main system unit and the high current T3Ster Booster, all current and voltage sources are available according to the requirements of the classical MIL-STD 750E while providing the superior transient measurement capabilities of the latest T3Ster technology of Mentor Graphics. For details refer to our white paper titled: Thermal transient measurement of high power bipolar transistors: chances and challenges.


T3Ster Master Software

T3Ster Master is an optional software tool (available on the Windows® operating systems) primarily aimed at postprocessing measurement results obtained by T3Ster equipment.

Results of multiple T3Ster measurement “projects” can be displayed in one single plot enabling users to quantify differences in structure functions e.g. failures in the heat-conduction path.


Besides advanced results presentation options, the latest version of T3Ster Master provides dynamic compact models in the form of Cauer-ladders. By using its import wizard, thermal transient curves from almost any source can also be postprocessed: simulated thermal transient (and all the descriptive functions derived from it) can be easily compared with measured ones (and with the descriptive functions identified from the measured data). Therefore, users can validate detailed simulation models with test results of packages. By comparing “measured” and “simulated” structure functions it is possible to identify where in the package the simulation model fails to match reality.


Besides the import wizard there is a dedicated link to Mentor Graphics’ CDF simulation tools (FloTHERM and FloEFD) to export dynamic compact models of packages created from the postprocessed thermal impedance curves. This option is ideal for thermal modeling of power semiconductor device packages such as power LEDs. Package models complete with data about light output characteristics obtained by TeraLED allows comprehensive simulation of LED based products with FloEFD. Compact thermal models created by T3Ster Master are also provided as a Spice netlist which can be utilized in electro-thermal circuit simulators such as Mentor Graphics’ ELDO product.


Learn more by reading how NXP Semiconductors used T3Ster and the related results evaluation software to quickly and easily characterize and validate their dynamic compact thermal models (DCTMs).


Onsite Set-up and Training

To help new users become productive quickly, onsite set-up and training services are available. Contact us for more information.



DynTIM is a high precision test environment designed to operate in connection with T3Ster. It measures thermal performance of thermal interface materials (TIM).


TeraLED offers combined thermal and radiometric/photometric characterization of high-power LEDs, used in combination with T3Ster thermal transient tester to form a comprehensive, automated LED testing station.

Technical Specifications

Power Driving Module

  • Switching Time 1 μs
  • Maximum Power Step 20 W in voltage jump, 100 W in current jump mode (switching from heating current to measurement current)
  • Switched voltage range -10.24 V..+10.23 V, with an LSB of 5 mV at a max. current of 2A
  • Heating current range -2 A..+2 A with an LSB of 1 mA at a max. device voltage of 7 V
  • Enhanced range: -200 mA .. +200 mA with an LSB of 0.1 mA

Measurement Current Sources

  • Number of sources: 4
  • Current Range -25.5 mA..+25.5 mA with an LSB of 0.02 mA

Measuring Unit (2 to 8 measurement channels)

  • Max. Differential Input Voltage ± 5 V
  • Max. Common Mode Voltage 10 V
  • Measurement Ranges 400 mV / 200 mV / 100 mV / 50 mV
  • Maximum Sampling Rate 1 MSa/s
  • Signal-to-noise Ratio (SNR) 70 dB
  • Resolution 12 bit (12 μV in the 50 mV range) Input Impedance 100 kΩ

Thermal Measurement Outputs (after post processing)

  • Measured Unit-Step
  • Thermal Response – ΔTJ(t)
  • Thermal Impedance – Zth(t)
  • Thermal Time Constant Spectrum
  • Complex Locus – Zth(ω)
  • Pulse Thermal Resistance
  • Structure Function (Differential and Cumulative)