SLVSD74D December 2015 – December 2019 TPS2H160-Q1
High-accuracy current sense is implemented in the version-B device. It allows a better real-time monitoring effect and more-accurate diagnostics without further calibration.
One integrated current mirror can source 1 / K(CS) of the load current, and the mirrored current flows into the external current sense resistor to become a voltage signal. The current mirror is shared by the four channels. K(CS) is the ratio of the output current and the sense current. It is a constant value across the temperature and supply voltage. Each device is calibrated accurately during production, so post-calibration is not required. See Figure 23 for more details.
When a fault occurs, the CS pin also works as a fault report with a pullup voltage, VCS(H). See Figure 24 for more details.
Use Equation 1 to calculate R(CS).
Take the following points into consideration when calculating R(CS).