US Patent 9391467 Step-up battery charging management system and control method thereof

In one embodiment, a battery charger can include: (i) a step-up converter configured to generate an output signal by boosting a DC input voltage, where a threshold voltage is greater than the DC input voltage; (ii) a charging control circuit configured to receive the output signal from the step-up converter, and to control charging of a battery; (iii) the charging control circuit being configured to regulate the output signal to maintain a charging current for the battery charging as a trickle current when a battery voltage is less than the threshold voltage; and (iv) the charging control circuit being configured to charge the battery directly by the output signal when the battery voltage is greater than the threshold voltage.