Figure 3-1 shows a board size comparison between two similar designs for a bi-directional brushed DC motor, such as a window lift. This application typically requires a peak power of 300W or less, and typical operating power around 100W.

The left image, a 12V design using the DRV8706-Q1 gate driver and four external n-channel MOSFETs, is preferred for motor currents typical of window lifts, around 20A peak and 8A in steady-state (although intermittent) operation. By choosing appropriate MOSFETs with low RDS(on) values, this design can be extended to higher currents.

The right image, a 48V design using the DRV8263-Q1 integrated full-bridge motor driver, is also preferred for window lift applications, with significant board size savings. The current levels with a 48V supply are less than 10A peak and only a few amps in steady-state operation. Note that beyond the reduction in driver size due to reduced current, the integration of the full-design into a single chip reduces the size of external components, most significantly the elimination of the large shunt resistor.

Figure 3-1 Comparison of Board Size for 12V and 48V Full-Bridge Motor Drivers