Patent ID: 7554836
Filing Date: 2009-06-30
Classification: G11C

Abstract:
1. A data write-in control circuit for writing data to a magnetic memory arranged at the across of a first conductive line and a second conductive line, the magnetic memory comprising a magnetic tunnel junction (MTJ) element having at least a synthetic anti-ferromagnetic free layer, a tunnel barrier layer, and a synthetic anti-ferromagnetic pinned layer, thus the data stored in the toggle magnetic memory is represented by the resistance dependent on the parallel or anti-parallel alignment of the magnetic moment configurations of two ferromagnetic layers adjacent to the tunnel barrier layer, the data write-in control circuit comprising: a first transistor; a second transistor connected to the first transistor in series; a transmission gate electrically connected to the first transistor; a comparing circuit having two input ends electrically connected to the first transistor respectively; a storage capacitor with one end electrically connected to the first transistor; and a logic circuit electrically connected to an output end of the comparing circuit; wherein the transmission gate turns on in response to an activating signal at an initial time interval to store an initial state voltage to the storage capacitor; the transmission gate turning off and conducting a first current of the first conductive line at a first time interval; conducting a second current of the second conductive line at a second time interval, and the comparing circuit outputting a comparison result according the voltages of the two input ends of the comparing circuit such that the logic circuit outputs a control signal in response to the comparison result from the comparing circuit and a data to be written; cutting off the first current of the first conductive line or the second current of the second conductive line in response to the control signal at a third time interval; and cutting off the second current of the second conductive line or the first current of the first conductive line at a fourth time interval.