ESD204: Max Junction Temperature of ESD204 4-Channel Low-Capacitance Surge and ESD Protection Diode

Hi Giselle,

From my understanding, the maximum junction temperature is the maximum operating temperature, which would be 125°C.

Please let me know if you have any additional questions!

Best Regards,

Josh Prushing

Hi John,

You are correct in your understanding. In the formula used to calculate Tj, the RθJA * PDEV portion will always be positive, and the max Ta would sum with this. This would indicate that the max junction temperature is higher than the max operating temperature, and I personally have never seen the max junction temperature to be higher than the max storage temperature, especially because the breakdown current used in the calculation (for PDEV) is often either 1mA or 10mA, which when multiplied with the RθJA will result in a much smaller number, often only a few degrees above the max operating temperature.

For instance, for ESD204, using the formula Tj = TA + RθJA * PDEV, see the following calculation:

TjMAX = TAMAX + RθJA * PDEVMAX

TjMAX = 125°C + (262.1°C/W * (7.9V * 0.001A))

TjMAX = 125°C + 2.07°C

TjMAX = 127.07°C

As you can see, this is much closer to the max operating temperature than to the max storage temperature of 155°C.

Please let me know if you have any questions!

Best Regards,

Josh Prushing