Patent ID: 7477076
Filing Date: 2009-01-13
Classification: G11C,H03F

Abstract:
1. A differential current-sensing amplifier comprising: a first inverter having a first output; a second inverter having a second output; a first resistor connected between the first inverter and ground, a current to be sensed input between the first resistor and the first inverter; a second resistor connected between the second inverter and ground, a reference current in relation to which the current to be sensed is compared input between the second resistor and the second inverter; a first switch connected between the first output and ground, the first switch turned off to compare the current to be sensed in relation to the reference current; a second switch connected between the second output and ground, the second switch turned off to compare the current to be sensed in relation to the reference current; a third switch connected between the first and the second inverters and power, the third switch turned on to compare the current to be sensed in relation to the reference current; a fourth switch connecting the current to be sensed to a point between the first resistor and the first inverter; a fifth switch connecting the reference current to a point between the second resistor and the second inverter; and, a NOR gate having inputs connected to the first and the second outputs, and an output controlling the fourth and the fifth switches.