• When DC is applied to pin3, current will flow through the transformer
and charges it. The current will generate .7 V on pin2. This is applied
to pin1 to turn it off.
• When the Inductor shuts off, the Inductor discharges the energy to the
secondary.
• Repeating the ON and OFF process causes a switching action. This
action causes the transformer to charge and discharge generating
generates Secondary Voltages.
• The IC’s startup voltage is through a high value resistor.
• When the IC functions, it drains current through pin4 and the supply is
insufficient and cannot continue to supply voltage to the IC.
The IC could Shut OFF due to insufficient Supply Voltage
• We want the IC to be permanently on and turn ON/OFF the FET. But
if the IC goes off, the control is not possible. Total reset occurs causing
a pulsating supply
