Patent ID: 9602004
Date: 2017-03-21
CPC Classifications: H02M

Claim:
1. A controller used in a buck-boost converter, wherein the buck-boost converter converting an input voltage into an output voltage comprises a first switch, a second switch, a third switch, a fourth switch and an inductor, the controller comprises: a logic control circuit configured to generate a logic control signal based on a reference signal and a feedback signal representative of the output voltage; a pulse width increasing circuit coupled to the logic control circuit, wherein the pulse width increasing circuit is configured to generate a sum control signal based on the logic control signal, and wherein the pulse width increasing circuit increases the pulse width of the logic control signal by a first predetermined value to generate the pulse width of the sum control signal; a pulse width decreasing circuit coupled to the logic control circuit, wherein the pulse width decreasing circuit is configured to generate a difference control signal based on the logic control signal, and wherein the pulse width decreasing circuit decreases the pulse width of the logic control signal by a second predetermined value to generate the pulse width of the difference control signal; a first driving circuit coupled to the pulse width increasing circuit, wherein based on the sum control signal, the first driving circuit generates a first driving signal and a second driving signal to respectively control the first switch and the second switch; and a second driving circuit coupled to the pulse width decreasing circuit, wherein based on the difference control signal, the second driving circuit generates a third driving signal and a fourth driving signal to respectively control the third switch and the fourth switch.