Control circuit and voltage regulation unit for switching power converter

The invention provides a control circuit suitable for a switching power converter and a voltage regulation unit in the control circuit. The voltage regulation unit according to various embodiments of the present disclosure may include a switch-type step-down regulation module and a low dropout linear regulation module. The control circuit comprises the voltage regulation unit, the switch type step-down regulation module can be coupled to the power input end of the control circuit and used for providing a step-down output voltage at the step-down output end of the switch type step-down regulation module, and the low-dropout linear regulation module can be coupled to the power input end and the step-down output end and used for providing the step-down output voltage at the step-down output end of the switch type step-down regulation module. The power supply is powered by the power input during a first working period and is powered by the step-down output voltage during a second working period. Therefore, when t