Charging circuits for portable communication terminals

摘要

Current sensing during recharging of a battery in a portable communication terminal is achieved without the use of a dedicated sense resistor. The type of charger attached to the terminal is established from the measured difference in potential between battery and charger. The accuracy of the computation of current in the charging circuit relies on estimated values of impedance and voltage drops across in-circuit components. Estimated values may vary in accordance with the current temperature of the components for which the estimates are derived. <IMAGE>