Summing Capacitance in Parallel
Parallel connection is the most common way to combine capacitors. When capacitors are wired in parallel, their total equivalent capacitance ($C_{eq}$) is simply the sum of all individual capacitances.
Benefits of Parallel Capacitance
- Increased Storage: If you need more 'energy buffer' in a power supply, you simply keep adding capacitors in parallel.
- Lower ESR: Using multiple small capacitors in parallel often results in a lower "Equivalent Series Resistance" than one large capacitor, allowing for faster charging and discharging.
- Voltage Safety: In a parallel circuit, every capacitor sees the same voltage. However, the total voltage must NOT exceed the rating of the weakest capacitor in the group.
The Formula
Where:
=
Equivalent Capacitance=
Individual CapacitancesExample Calculation
You have a circuit with a $100 , \mu\text{F}$, a $220 , \mu\text{F}$, and a $47 , \mu\text{F}$ capacitor in parallel.
- Sum them up: $100 + 220 + 47 = 367 , \mu\text{F}$.
The total equivalent capacitance is $367 , \mu\text{F}$.