⭐️ Power Smoothing and Time Constant⭐️

Prolonged usage aside, capacitors do a very good job of evening out momentary drops in power. The time constant tau indicates this capability. Tau equals resistance times capacitance: τ = RC Tau indicates the amount of time in seconds that it takes a voltage to decay exponentially to 37 percent of its original value. At five times this number, the capacitor is considered fully discharged. If a capacitor attaches across a voltage source that varies (or momentarily cuts off) over time, a capacitor can help even out the load with a charge that drops to 37 percent in one time constant. The inverse is true for charging; after one time constant, a capacitor is 63 percent charged, while after five time constants, a capacitor is considered fully charged. For example, if you had a circuit as defined in Figure 1 above, the time constant of the RC circuit is: 1000 ohms x 47 x 10-6 farads This time constant works out to .047 seconds. When we disconnect the 5V source seen here, it takes .047 seconds to drop to 1.85V, and five times this, or .235 seconds, to discharge. If the capacitor charged up to 5V, that process would also take .235 seconds. You can use a larger capacitor to increase these numbers depending on the situation or load in question. Enjoy...😎

published 6 years ago