When designing PCB, in order to stabilize the power supply, should the more capacitors be put, the better? Why all put both 0.1uf and 10uf capacitors? And some put three capacitors. So, what kind of capacitors should be used? How many should be used? And what is the capacitance value?
For the capacitor, it is the filter function, which is to filter off and clear out the clutter. Generally, 10uF is better for low-frequency clutter. And it can effectively filter out low-frequency clutter. But it is inductive to high-frequency clutter, and has a lot of impedance, and thus cannot filter out high-frequency clutter. And 2.2uF and 47uF are also be used.
The high-frequency clutter must be filtered out with a 0.1uF capacitor. On the contrary, the 0.1uF capacitor cannot filter out the low-frequency clutter. There is also a 0.01uF capacitor, which is to filter out UHF clutter.
So it is the securest to put three capacitors: 10uF, 0.1uF and 0.01uF. Where to put them? Generally, put 0.01uF and 0.1uF capacitors close to the power pins of the chip process high-frequency signals, and the 10uF can be placed a little farther. It is even enough to put only one 10uF at 3 or 4 power pins.