MB3789
(2) Low input voltage malfunction preventive circuit
The transient state or a momentary decrease in supply voltage, which occurs when the power supply is turned
on, may cause errors in the control IC, resulting in breakdown or degradation of the system. The low input
voltage malfunction preventive circuit detects the internal reference voltage level according to the supply voltage
level and, if the input voltage is low, turn off the output transistor and maintains the SCP pin (pin 5) at 0 V while
making the dead time 100%.
The circuit restores voltage supply when the supply voltage reaches its threshold voltage.
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