Thanks for your response.
Are there no problems if they connect NCP1034(PWM Buck controller in CCG3 EVK) and CCG3PA?
CCG3 power is controled by VSEL1,2 output pins. CCG3PA output is based on FB control.
The buck controller used in CCG3 EVK NCP1034 also works similar to the one used in CCG3PA power board i.e. through analog feedback.
In CCG3 EVK we are using select lines to alter the feedback voltage to the Buck controller by changing the resistor divider pull down value keeping the feedback reference voltage (Vref) same. In CCG3PA we are directly providing the Feedback voltage to the buck-boost converter.
Please note that we do not have any reference design of CCG3PA with Buck converter.