Power supply start up booster circuit

A power supply start up booster circuit for providing an increased startup voltage for a switch mode control integrated circuit comprising:

• a boost portion for combining a first input voltage that has a predetermined minimum value and a second input voltage that transitions from 0 volts to the predetermined minimum value to make a minimum threshold voltage;
• a control portion having an integrated circuit for using the minimum threshold voltage to temporarily provide a voltage input at said integrated circuit;
• an output portion for providing a permanent voltage input at said integrated circuit and an output supply voltage to an external circuit;
• said boost portion comprising a first capacitor for storing said first input voltage and then adding said first input voltage to said second input voltage once said second input voltage transitions to said predetermined minimum value, a first transistor having a collector connecting said first input voltage through said first capacitor and having an emitter connected to ground, said first input voltage charging said first capacitor when said first transistor is in an ON state, a second transistor having a base connected to said second input voltage through a first resistor and a collector connected to said base of said first transistor providing a turn ON voltage to a base of said first transistor, said second input voltage charging said first capacitor when said second transistor is in an OFF state, a first diode connected between said first input voltage and said first capacitor for preventing current flow to first input voltage from a positive side of said first capacitor, a second diode connected between said second input voltage and said first capacitor for preventing current flow from a negative side of said first capacitor to said second input voltage, a third diode connected between said first capacitor and said control portion for preventing current flow to the positive side of said first capacitor from said control portion, and a fourth diode connected between said second input voltage and said control portion for providing an additional path to charge said control portion and to prevent current flow from said controls portion to said second input voltage.