What is the difference between Tj(max) and Tj(op)?

The maximum allowable temperature for the chip during conventional continuous operation is specified in Tj(op). Please ensure the maximum chip temperature stays at or under Tj(op) during conventional continuous operation. The maximum allowable temperature for a chip during short-term overload or abnormal operation is specified inTj(max).

How do I estimate the junction temperature (Tj)?

Junction temperature can be estimated based on generated losses and thermal resistance Rth(j-c). For details, refer to Application Manual Chapter 6-2.1. We provide a free software to calculate IGBT’s temperature at 2-level inverter, 3-level inverter, and chopper circuits. This software can be downloaded here.

What is the acceptable range of case temperature (Tc) for an IGBT module?

Refer to the “Maximum Ratings: Case temperature” section in the data sheet.

What functions do the IGBT Simulator have?

The IGBT Simulator can estimate the power loss and temperature for a 3-phase 2-level inverter circuit, 3-phase 3-level inverter circuit, and chopper circuit of an IGBT and FWD. It can also calculate loss and temperature under variable inverter operation conditions such as output current and switching frequency. Changes in loss and temperature when the load […]

How do I calculate IGBT losses?

Fuji provides a free software to calculate the IGBT losses. The following steps can be followed to obtain the figure. (1) Download our Loss Simulator (2) Launch our Loss Simulator (3) Enter data on the chip series, circuit configuration, voltage rating, and current rating. Select your model type. Click “”Next”” (4) Enter data on the […]

Is there a temperature dependency in the IGBT’s maximum collector-emitter voltage (VCES)?

A lower temperature reduces the IGBT’s maximum collector-emitter voltage (VCES). The data sheet describes the maximum collector-emitter voltage (VCES) under the condition of Tj=25oC. Refer to the technical information describing temperature dependency included in the technical documents under Design Support.

Can an IPM operate at -40oC?

Our IPM is designed with a lowest guaranteed operating temperature of Tc=-20oC. Operation below this temperature has not been evaluated, and any use below -20oC will void your warranty. At such temperature, there are concerns about possible malfunctions due to a lower device withstand voltage or reduced capacity of the used capacitor.

What is the lowest operation temperature for an IGBT module?

The minimum temperature is specified by the storage temperature (Tstg). Please consider that there will be a reduced device withstand voltage and peripheral component (capacitor, control circuit) characteristics under low temperature before use.

What precautions need to be considered when designing an IGBT drive circuit?

Refer to Application Manual Chapter 7-5. It provides precautions regarding the photo-coupler’s noise capability, wiring between the drive circuit and IGBT, and gate overvoltage protection.

Can application of a reverse-bias voltage (-VGE) on a gate-to-emitter be exempted in a case where only an FWD is used without an opposite IGBT, such as in a chopper circuit?

Please apply a reverse-bias voltage (-VGE) of -5 V or higher (-15 V recommended; max. -20 V) between the gate and emitter in the IGBT that is not being used. An insufficient reverse-bias voltage (-VGE) may cause the IGBT to misfire due to dV/dt at the time of reverse-recovery of the FWD, resulting in damage. […]