Capacitor Considerations for Power Management

Portable electronic devices demand maximum battery performance. This demand for ever increasing power has outpaced the rate of battery development in the electronics industry. Power management in portable electronic devices has thus become a critical area for circuit design and component selection, in the development cycle for portable electronic devices. Low energy designs improve mean time between charging (MTBC). Design in of capacitors with maximized insulation resistance (IR) and minimized equivalent series resistance (ESR) may be a useful tool in minimizing battery drain rate. In this paper, use of capacitors in typical battery operated applications is modeled with respect to leakage current and ESR for several types of capacitors available from several manufacturers. IR is measured for each and the data are used to model anticipated MTBC performance as a function of use conditions in generic applications. The effect of ESR and insulation resistance on anticipated MTBC is predicted. The use of lower ESR capacitors, which are highly consistent in capacitance and inductance from capacitor to capacitor, in the design of battery operated electronic devices is projected to improve performance significantly.