In an RC circuit, the value of the time constant (in seconds) is equal to the product of the circuit resistance (in ohms) and the circuit capacitance (in farads), i.e. R × C. It is the time required to charge the capacitor, through the resistor, to 63.2% of full charge; or to discharge it to 36.8% of its initial voltage. read more
Circuits are occasionally drawn without capacitors, as it is implicit that they will be included on every logic power pin. Obviously if using an EDA tool, they must be on the schematic somewhere (usually disembodied in some corner), but it is implied that there will be at least one on each pin (multiple caps can cover a wider range of frequencies), and as close as possible. read more
Capacitor used for charging and discharging of electric field.(e.g, rectifier circuits) It also used for filtering actions in passive filter circuits. read more
If you use a capacitor with low capacitance, it will discharge quickly and give the output voltage in a wide range like 5 to 9V (for 9V output). Regulator circuit may not accept this wide range of input for regulation. Hence, it is recommended to use high value capacitors like 1000uF or 4700uF capacitor as a filter. read more