Patent ID: 6407619
Filing Date: 2002-06-18
Classification: H03L

Abstract:
A charge pump circuit comprising:a first current mirror circuit through which a charge-up current flows; and a second current mirror circuit through which a charge-down current flows; wherein a charge pump current corresponding to the difference between said charge-up current and said charge-down current is output as an output signal; said first current mirror circuit comprises first and second current sources, and a first reference transistor which is connected to said first current source and generates a first reference potential in response to the activation of a first comparison signal, and is connected to said second current source and generates a second reference potential in response to the deactivation of said first comparison signal; and a first output transistor through which said charge-up current flows in response to application of said first reference potential, and which turns off in response to application of said second reference potential; and said second current mirror circuit comprises third and fourth current sources, and a second reference transistor which is connected to said third current source and generates a third reference potential in response to the activation of a second comparison signal, and is connected to said fourth current source and generates a fourth reference potential in response to the deactivation of said second comparison signal; and a second output transistor through which said charge-down current flows in response to application of said third reference potential, and which turns off in response to application of said fourth reference potential.