The RT9554A is designed for over-current detection. The current sense amplifier amplifies the voltage across resistor which is connected between CSP and CSN by 200. The amplified voltage is compared with the voltage of BAT_REF and check whether over-current happens or not. The RT9554A also provides a comparator with two input pins, AC_REAL and AC_REF for users. There is an output pin FLAG as an indicator which is a N-MOSFET in open-drain configuration. Users can connect one resistor between the FLAG pin and supply voltage. Either over-current condition occurs or the AC_REAL voltage is larger than the AC_REF voltage, the FLAG is pulled low. The RT9554A is a available in the WDFN-8L 2x2 package.
Applications