US 12,438,461 B2
Switching regulator with ramp injection switch
Zheyuan Tan, San Jose, CA (US)
Assigned to Renesas Electronics America Inc., Milpitas, CA (US)
Filed by Renesas Electronics America Inc., Milpitas, CA (US)
Filed on Feb. 1, 2023, as Appl. No. 18/162,932.
Prior Publication US 2024/0258919 A1, Aug. 1, 2024
Int. Cl. H02M 3/158 (2006.01)
CPC H02M 3/158 (2013.01) 16 Claims
OG exemplary drawing
 
1. A switched mode power supply comprising:
a high side power switch coupled to a low side power switch at a switching node;
a ramp injection circuit coupled to the switching node, wherein the ramp injection circuit comprises a ramp switch; and
drive the high side power switch and the low side power switch;
receive a first signal indicative of a state of the high side power switch;
receive a second signal indicative of a state of the low side power switch;
generate, based on the first signal and the second signal, a control signal for controlling the ramp switch;
use the control signal to turn off the ramp switch when the switch mode power supply enters a tri-state; and
use the control signal to turn the ramp switch back on when the switch mode power supply exits the tri-state,
wherein the tri-state occurs when both the high side power switch and the low side power switch are turned off when the switched mode power supply operates in a discontinuous current mode.