I want to know the function of C 1300 and C 130 1 in the figure below. What effect will it have if it is too small? I'm a rookie on the tour. Don't laugh at me.

C 1300: it is the power supply decoupling filter capacitor. If it is very small, it may cause mutual interference between circuits through the power supply, or there are high-frequency signals connected in series to the IC, resulting in unstable operation.

C 130 1: due to the incomplete circuit, it may be a clutter filter capacitor, which is too small to be sensitive to clutter and its anti-interference ability is reduced; It can also be an integrated capacitor. If the time constant is too small, the circuit may not work.