SLVSHD4 October 2024 DRV8376
ADVANCE INFORMATION
The SOx pin on the DRV8376 outputs an analog voltage proportional to the current flowing in the low-side FETs multiplied by the gain setting (GCSA). The gain setting is adjustable between four different levels which can be set by the GAIN pin (in the hardware device variant) or the GAIN bits (in the SPI device variant).
Figure 7-20 shows the internal architecture of the current sense amplifiers. The current sense is implemented with the sense FET on each low-side FET of the DRV8376 device. This current information is fed to the internal I/V converter, which generates the CSA output voltage on the SOX pin based on the voltage on the VREF pin and the Gain setting. The CSA output voltage can be calculated as :
Figure 7-21 and Figure 7-22 show the detail of the amplifier operational range. In bi-directional operation, the amplifier output for 0V input is set at VREF/2. Any change in the differential input results in a corresponding change in the output times the CSA_GAIN factor. The amplifier has a defined linear region in which it can maintain operation.