Patent ID: 8760219

Claim:
A current providing circuit, for providing an output current at an output terminal, comprising: a current providing module, coupled to a first predetermined voltage level, for providing the output current according to the first predetermined voltage level and a control voltage transmitted to the current providing module; and a control voltage generating module, for generating the control voltage corresponding to the first predetermined voltage level and a threshold voltage of the current providing module, comprising at least one part of the current providing module to generate a control current based on the first predetermined voltage level and the threshold voltage of the current providing module; wherein the control voltage generating module further generates the control voltage according to the control current; wherein the control voltage generating module includes at least a capacitor, for generating a charging voltage according to the control current and a second predetermined voltage; wherein the control voltage generating module comprises a voltage detector for receiving the charging voltage directly from the capacitor and comparing the charging voltage and a reference voltage, where the control voltage generating module generates the control voltage according to a voltage detecting result of the voltage detector; wherein the control voltage generating module includes a control logic circuit comprising the voltage detector, for generating the control voltage according to the charging voltage; wherein the current providing module generates the output current only when the charging voltage is less than the reference voltage; wherein the control logic circuit further comprises: a NAND gate, for receiving the voltage detecting result and an enable signal to generate the control voltage according to the voltage detecting result and the enable signal.