Title :
Novel dynamic ramp circuit with input feedforward for voltage-mode DC-DC buck converter
Author :
Yuan Bing ; Lai Xinquan ; Zhao Lingling
Author_Institution :
Minist. of Educ., Xidian Univ., Xi´an, China
Abstract :
A novel dynamic ramp circuit with input feedforward technique for voltage-mode DC-DC buck converter is presented. By converting a charging current proportional to input voltage skillfully, the ramp amplitude varies with input voltage and the gain of modulator maintains substantially constant. Also the minimum value of the saw-tooth wave could be set freely by the introduction of clamp circuit. The proposed circuit can improve the stability and line transient response under various input voltages. A monolithic DC-DC buck converter with 2.25MHz frequency using the proposed circuit has been fabricated with a 0.5μm CMOS process for validation. With 2V line transient response, the undershoot and overshoot output voltages are about 35mV and 30mV, respectively.
Keywords :
DC-DC power convertors; feedforward; charging current; dynamic ramp circuit; frequency 2.25 MHz; input feedforward; overshoot output voltages; sawtooth wave; size 0.5 mum; undershoot output voltages; voltage 2 V; voltage mode DC DC buck converter; Capacitors; Circuit stability; Feedforward neural networks; Modulation; Stability analysis; Transient response; Voltage control; DC-DC buck converter; Input feedforward; high frequency; voltage mode control;
Conference_Titel :
Radio-Frequency Integration Technology (RFIT), 2014 IEEE International Symposium on
Conference_Location :
Hefei
DOI :
10.1109/RFIT.2014.6933247
