Patent ID: 7388409
Filing Date: 2008-06-17
Classification: G11C

Abstract:
1. An offset independent sense circuit comprising: a balance circuit, having a first and second inputs and a first and second outputs, operative to produce an offset current at the first output when a first voltage is switched to the first and second inputs; a capacitor, connected to the first output, for storing the offset current; a second transistor connected between the first output and the capacitor; wherein the balance circuit comprises: a first current source, connected to the second output, for providing a first current; a second current source for providing a second current as large as the first current; a third transistor connected to the second output; a first resistor connected between the first input and third transistor; a current mirror having a reference branch connected between the first resistor and third transistor, and a mirror branch connected to the first output; a fourth transistor, connected to the second current source, for conducting a third current; and a second resistor connected between the second input and fourth transistor.