SLVSFV1B August 2018 – August 2021 DRV8350F , DRV8353F
PRODUCTION DATA
In this application example the device is configured for dual supply operation. dual supply operation helps to decrease the internal power dissipation by providing the gate driver with a lower supply voltage. This can be derived from the internal buck regulator or an external power supply. The junction temperature is estimated in the example below.
Use Equation 5 to calculate the value of IVCP and IVGLS for a MOSFET gate charge of 78 nC, 1 high-side and 1 low-side MOSFETs switch at a time, and a switching frequency of 20 kHz.
Use equation Equation 36, Equation 37, Equation 38, , and Equation 39 to calculate the value of Ptot for VVM = 12 V, VVDRAIN = 48 V, VVIN = 48 V, IVM = 9.5 mA, IVCP = 1.56 mA, and IVGLS = 1.56 mA.
Lastly, to estimate the device junction temperature during operation, use Equation 40 to calculate the value of TJmax for TAmax = 105°C, RθJA = 26.1°C/W for the RGZ package, and Ptot = 0.22 W. Again, note that the RθJA is highly dependent on the PCB design used in the actual application and should be verified. For more information about traditional and new thermal metrics, refer to the Semiconductor and IC Package Thermal Metrics application report.