When capacitors are connected together in parallel the total or equivalent capacitance, CT in the circuit is equal to the sum of all the individual capacitors added together. This is because the top plate of capacitor, C1 is connected to the top plate of C2 which is connected to the top plate of C3 and so on.
You often can achieve higher ripple current rating and lower ESR by using multiple capacitors in parallel rather than a single cap of the same total capacitance and voltage rating. Improving these ratings translates to longer lifetime. The cost is likely to be a bit higher using multiple caps, but not always.
High value polarised capacitors typically do not have ideal characteristics at high frequencies (e.g. significant inductance), so it's fairly common to add a low value capacitor in parallel in situations where you need to worry about stability at high frequencies, as is the case with 78xx regulator ICs such as this.
Well, just replace C1 in the circuit above with a 100 µF and a 47 µF capacitor in parallel, and you end up with a total capacitance of 147 µF. Another typical place where you’ll see capacitors connected in parallel is with microcontroller circuits. Microcontroller chips often have several power pins.
Tuning Circuits: Capacitors in series and parallel combinations are used to tune circuits to specific frequencies, as seen in radio receivers. Power Supply Smoothing: Capacitors in parallel are often used in power supplies to smooth out voltage fluctuations.
which means that the equivalent capacitance of the parallel connection of capacitors is equal to the sum of the individual capacitances. This result is intuitive as well - the capacitors in parallel can be regarded as a single capacitor whose plate area is equal to the sum of plate areas of individual capacitors.
Sometimes it is useful to connect several capacitors in parallel in order to make a functional block such as the one in the figure. In such cases, it is important to know the equivalent capacitance of the parallel connection block. This article …