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High Tj TRIACs
New high-performance 150 °C junction temperature TRIAC series

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The new high junction temperature TRIAC series, known as HiTj, can be used in hot environments, and also wherever high power density is needed on the PCB. Their extreme ruggedness eliminates the need for the usual RC snubber circuit, and due to their considerable thermal margin (Tj= 150 °C) with no derating whatsoever, they can use minimal size heatsinks.
High Tj TRIACs
This is the first time that such performance is proposed while common practices correspond to a standard derating of the performance at 150 °C, this new series secures the application operation even in dense or harsh operating conditions with minimal heatsink and snubber budget.

High Tj TRIACs
New high Tj TRIAC series allows new thermal design rules

Increasing the maximum operating junction temperature allows:
A reduced heatsink (Rthca), or
An increase in the maximum ambient temperature of the application, or
An increase in the RMS current

High power density on board


The further thermal margin offered by the new HiTj TRIACs is a real asset when increasing power. Where a conventional 125 °C TRIAC has to be dimensioned as X-size for a given operation, a Hi Tj is X-1 or X-2, reducing the global cost of the application.

Hot ambient temperature


In some cases, industrial applications operate at a hot ambient temperature. For outside applications (lighting, automation), or when the PCB is in a confined enclosure (vacuum cleaners, washing machines), the higher max operating junction temperature of the new HiTj TRIACs solves this technical constraint.

How to solve the 150 °C challenge


The key factors enabling construction of a TRIAC able to operate up to 150 °C are the reliability and the leakage current. These constraints were taken into account at the design stage.
A critical intrinsic parameter of the TRIAC is its ability to turn-off properly. The turn-off capability (di/dt)c is strongly dependent on the junction temperature. In order to avoid the risk of losing control at high temperatures due to the inability to switch-off, the new HiTj series has a switch-off capability 3 to 4 times higher than the first harmonic current slope, coping with currents affected by superimposed noise ripple due to loads of the brush motor type.

A medium power portfolio


The new series is ideal for vacuum cleaners and washing machine drum motors where heatsink size is critical due to raw material prices. 8 to 20 A devices are instrumental for 800 to 2000 W motor range.


T8xxH
T10xxH
T12xxH
T16xxH
T20xxH
ITRMS
8 A
10A
12A
16A
20A
TJMAX
150°C with no derating
VDRM
600 V
IGT
35 or 50
dV/dt
1000 to 1500 V/μs min
(di/dt)c
3 to 4 times the nominal value