Hi Team,
I want to use this PMOS as attached:
Thanks,
Shlomi
Hi Shlomi,
Thanks for promoting TI FETs at your customers. In theory, the body diode can conduct the same maximum current as the FET channel. However, there is a constant forward voltage drop for the diode that limits the maximum power that can be dissipated by the device. The maximum continuous current and power dissipation specified in the datasheet are calculated values as detailed in the blog below. We can use the same approach for the body diode. For the minimum pad, the typical thermal impedance is 230C/W and the maximum power dissipation can be calculated as follows: PDmax = (TJmax - Tamb)/RthetaJA = (150C - 25C)/230C/W = 0.54W. This needs to be adjusted for higher ambient temperature and for different pad geometry and board stackup that can change (raise or lower) RthetaJA. In practical designs, 0.5W max power dissipation is a good guideline. Please see the technical article below. The body diode forward voltage drop at 1.5A and Tcase = 125C is about 0.7V which gives a power dissipation = 1.5A x 0.7V = 1.05W. I think it is going to be difficult to dissipate this much power in the package for 30s (which can be considered DC or continuous).
