A end-point prediction scheme with constant amplitude ramp signal suitable for high voltage applications

A novel constant amplitude ramp sub-optimum end-point prediction scheme for voltage-mode buck converters is presented. During reference tracking, the PWM controller input voltage is estimated and set directly by some control circuit and the error amplifier output voltage remains almost unchanged. A circuit implementing a first order variable coefficient linear function is employed in this design. This enables the use of constant magnitude ramp signal, which makes the resulting design suitable for both low voltage and high voltage applications. Simulation results show that the reference tracking speed of the buck converters can be improved by about 6 times.