Pulsewidth control loop circuit using combined charge pumps and miller scheme

This work presents combined charge pumps and miller scheme for pulsewidth control loop (PWCL) circuit. Two charge pumps are combined to share common current sources to enhance the stability of the current source. A miller capacitance is applied between the two charge pumps to obtain 75% area reduction of the capacitor. The scheme using phase blending scheme and miller capacitance obtains 30% reduction of the voltage ripple. The accuracy of duty cycle as well as the operating frequency range and stability of the loop can be improved.