ZHCSND1A November 2020 – May 2022 DRV8434
PRODUCTION DATA
The current path for a motor connected in full-bridge is through the high-side FET of one half-bridge and low-side FET of the other half-bridge. The conduction loss (PCOND) depends on the motor rms current (IRMS) and high-side (RDS(ONH)) and low-side (RDS(ONL)) on-state resistances as shown in Equation 3.
The conduction loss for the typical application shown in Table 8-1 is calculated in Equation 4.
This power calculation is highly dependent on the device temperature which significantly effects the high-side and low-side on-resistance of the FETs. For more accurate calculation, consider the dependency of on-resistance of FETs with device temperature.