Control method and control circuit for a boost converter

A control circuit for a boost converter, the control circuit comprising:

• a) a comparison circuit configured to compare an input voltage of said boost converter against an output voltage of said boost converter, and to generate first and second control signals;
• b) an option circuit comprising first and second switches, and being configured to provide a third control signal from a drive circuit of said boost converter to a gate of a synchronous power transistor of said boost converter, in accordance with said first and second control signals, and when said output voltage is greater than said input voltage, wherein said first switch is directly connected between said third control signal and said gate of said synchronous power transistor, wherein said gate is a front control gate that is on an oxide layer and not in a substrate of said synchronous power transistor;
• and
• c) said option circuit being configured to provide said input voltage to said gate of said synchronous power transistor, in accordance with said first and second control signals, in order to provide a current path for an inductor current of said boost converter through said synchronous power transistor, and when said output voltage is not greater than said input voltage, wherein said second switch is directly connected between said input voltage and said gate of said synchronous power transistor.