chargereservoir

Charge reservoir is a term used in electronics to denote a component or network that stores electric charge and can release it to a circuit when needed. It acts as a local store of energy to supply instantaneous current and help stabilize voltage during transient loads. In circuit models, a charge reservoir is often represented as a capacitor with Q = C V, where C is the effective capacitance of the reservoir.

Real implementations include capacitors, supercapacitors, batteries, and energy-storage modules. On integrated circuits, on-chip capacitances and buffer storage may serve as miniature reservoirs. The effective performance depends on the reservoir's capacitance, its equivalent series resistance (ESR), leakage, and aging. Higher C provides greater charge storage and slower voltage droop, while ESR determines how quickly the reservoir can respond to load changes.

Applications include decoupling and power-supply smoothing, peak-current delivery for digital circuits, and buffering in analog and mixed-signal circuits. In switching power supplies, reservoir capacitors provide instantaneous energy during switching events, reducing voltage ripple.

Design considerations involve balancing size, cost, and performance: larger reservoirs store more energy but take more space and can introduce unwanted parasitics; low leakage and low ESR are desirable but can be expensive.

The concept is widely used in electronics to maintain stable operation during dynamic load conditions.