Switching regulator with ramp injection switch

Abstract

A switched-mode power supply, such as a constant on time regulator, is presented. The switched-mode power supply includes a high side power switch coupled to a low side power switch at a switching node. A ramp injection circuit is coupled to the switching node and a ramp switch is coupled to the ramp injection circuit are also provided. A driver is used to drive the high side power switch and the low side power switch and to control the ramp switch. The driver turns off the ramp switch when the switch-mode power supply enters a tri-state, and turns the ramp switch back on when the switch-mode power supply exists the tri-state. The tri-state occurs when the switched-mode power supply operates in a discontinuous current mode, when both the high side power switch and the low side power switch are turned off.

Dependencies are inferred from the claim text.