Patent ID: 9509157
Filing Date: 2016-11-29
CPC Classification: H02J,H02M

Claim Text:
1. A power bank device, comprising: a load node for connecting to a load outside the power bank device; a power-supply circuit, for providing an output current to the load node, wherein an initial value of the output current is according to a sink of the load; an output circuit, for generating an output voltage at the load node according to the output current, wherein the output circuit comprises an impedance circuit; a detecting unit, for generating a detecting signal according to the output current, wherein when the initial value of the output current is below a predetermined current value, the detecting unit generates a detecting signal with a first value, and when the initial value of the output current is above the predetermined current value, the detecting unit generates a detecting signal with a second value; a switching unit, for switching an impedance of the impedance circuit from a first impedance to a second impedance, wherein an impedance of the first impedance is larger than an impedance of the second impedance, and the output voltage of the output circuit is reduced by the second impedance; and a control circuit, for controlling the switching unit to switch to the impedance of the impedance circuit according to the detecting signal, wherein the control circuit controls the switching unit to switch the impedance of the impedance circuit from the first impedance to the second impedance when the detecting signal has the second value so as to reduce the output voltage and then reduce the output current to the load node when the load is changed from a low load to a high load; wherein the switching unit is coupled between the impedance circuit and the control circuit.