Patent ID: 7965058

Claim:
A method of manufacturing a USB-compliant charging and power supply circuit, the method comprising: forming a switch-mode battery charging circuitry with: an external power input adapted to receive external power from an external power source; an output node adapted to supply output power to: an electronic system of an electronic communication device; and a battery, via a switch; an inductor; an integrated circuit arranged to cooperate with said inductor to supply said output power with a current of greater magnitude than current of said external power; and forming a battery isolation circuitry with: said switch; a reference voltage input adapted to receive a reference voltage from said electronic system; a voltage divider adapted to determine, based on said reference voltage, a minimum voltage value needed at said output node; an op-amp adapted to: sense that a voltage at said output node is below said minimum voltage value; and control, responsive to said sensing, said switch to restrict current of said output power to said battery, thereby increasing a power allocated to said electronic system.