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(1)Under voltage lock out (UVLO)
This function places the IC in the standby state when the input voltage drops below the specified input voltage so that the internal circuit becomes unstable and malfunction does not occur.
This function protects against degradation and destruction due to heat generation of the device itself when the output terminal VOUT goes into an unintentional short mode state. There are two types of overcurrent protection: the foldback type that simultaneously reduces the output current and output voltage, and the current limiter type that reduces the output voltage while keeping the output current constant.
(3)Thermal shut down (TSD)
It is a circuit to prevent deterioration and destruction of the device because of remarkable ambient temperature rise, heat generation of the device itself due to unintentional high current load etc. When the specified temperature is detected by the internal temperature detection circuit, the output transistor is turned off.
When the output transistor is turned off, the terminal voltage of VOUT may remain for a certain time depending on the load capacitance connected to the output terminal. This circuit rapidly discharges the charge accumulated on the load side and drops the VOUT terminal voltage to near the IC GND.