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The specified input voltage value of the EN (CTRL) pin will not be the same since it is dependent on the supply voltage. When using with IN=3.3V refer to the following graphs in the datasheet. BD6520F and BD6522: Control Input Voltage vs Supply Voltage, BD6524HFV: EN Input Voltage vs Ambient Temperature, and for other models: EN, /EN Input Voltage vs Supply Voltage.
If the switch is turned ON while connected to a load exceeding the overcurrent limit value (short-circuit output current), the output current is limited to the overcurrent limit value and not the overcurrent detection value. Turning ON the load after turning ON the switch makes it possible to output a current over the overcurrent limit value.
When overcurrent is detected and the current is limited, once the output current falls below the limited current normal operation resumes and the output current returns.
. With backflow models, if a higher voltage is supplied to OUT vs IN when the switch is OFF (EN=OFF), current may flow (i.e. through a parasitic diode), which can lead to deterioration and breakdown. If applying a higher voltage to OUT than IN, please use a model that can prevent backflow. Applicable models are described as providing 'reverse current protection while the switch is OFF' in the datasheet.Related Link:Technical Document
If the switch turns ON when a resistive load exceeding the overcurrent limit (short-circuit output current) is connected, overcurrent is detected and the output current is immediately limited to the overcurrent limit value. The output voltage at this time is 'Overcurrent Limit Value (Short-Circuit Output Current) x Load Resistance Component'. Besides this, there is a possibility of a short-circuit between the output and ground.Related Link:Technical Document
There should be no problems even if a large capacitance capacitor (USB standard, 120uF or more) is connected to the output. However, when the IC turns ON and the output rises the capacitor CL is charged, causing inrush current to flow. Depending on the value of CL, the inrush current is restricted to the current limit value and the IC enters an overcurrent detection state. If the high-side switch IC continues in this state for more than the /OC pin (flag) output delay time, 'L' is output from the /OC pin.
One recovery method involves turning OFF the EN (CTRL) pin and then turning it ON again or turning the power supply OFF then ON, or going below VTUVL(VUVLOL) then above VTUVH(VUVLOH).
The output voltage in the overcurrent limited state fluctuates according to 'Current Value Limit (Short-Circuit Output Current) x Load Resistance Component'.
The ramp waveform is measured using an electronic load device (constant current mode). After overcurrent is detected, since the device continues the current even after the IC output is current limited, the output voltage will be 0V.