Re: How to design for low ripple Amplifier?
As the output of switch is connected to RC circuit, by increasing the time constant of RC circuit i.e. by increasing value of R or C or both can reduce the switching ripple size.
If the RC circuit is connected to another circuit with very low input impedance, it may create loading problem for the 1nF cap and the switching ripple size will be bigger both in amplitude and time. So, increasing the input impedance of circuit next to cap or increasing C or both R and C can solve the problem. The other way is to decrease switching delay to less than 1 us. Increasing the value of C also will help in reducing discontinuous noise due to change from 10V to 13V or vice versa.
Hope that helps.