SLVSDS7B August 2019 – November 2019 DRV8876
In the alternative application for two half-bridge loads, the IPROPI output will be the combination of the two outputs currents. The current sense feedback resistor RIPROPI should be scaled appropriately to stay within the dynamic voltage range of the controller ADC. An example of this is shown
If VADC = 3.3 V, IPEAK1 = 1 A, IPEAK2 = 0.5 A, and AIPROPI = 1000 µA/A455 µA/A then to maximize the dynamic IPROPI voltage range an RIPROPI of approximately 2.2 kΩ should be selected.
The accuracy tolerance of RIPROPI can be selected based on the application requirements. 10%, 5%, 1%, 0.1% are all valid tolerance values. The typical recommendation is 1% for best tradeoff between performance and cost.
In independent half-bridge mode, the internal current regulation of the device is disabled. VREF can be set directly to the supply reference for the controller ADC.