Low sensing current non-volatile flip-flop

摘要

A low sensing current non volatile flip flop includes a first stage to sense a resistance difference between two magnetic tunnel junctions (MTJs) and a second stage having circuitry to amplify the output of the first stage. The output of the first stage is initially pre-charged and determined by the resistance difference of the two MTJs when the sensing operation starts. The first stage does not have a pull-up path to a source voltage (VDD), and therefore does not have a DC path from VDD to ground during the sensing operation. A slow sense enable (SE) signal slope reduces peak sensing current in the first stage. A secondary current path reduces the sensing current duration of the first stage.

主权项

1. A magnetic tunnel junction (MTJ) flip flop apparatus, comprising a first stage including a first MTJ and a second MTJ coupled to the first MTJ, the first stage including a first low current sense path from a first precharge node through the first MT; and a second low current sense path from a second precharge node through the second MTJ; and
a second stage separate from the first stage, the second stage including a third current sense path from a supply voltage node to a ground node via a first second stage transistor and a fourth current sense path from the supply voltage to the ground node via a second second stage transistor, in which the third current sense path excludes the first precharge node and the fourth current sense path excludes the second precharge node; and wherein the first second stage transistor includes a first second stage transistor gate coupled to the second precharge node, and the second second stage transistor includes a second second stage transistor gate coupled to the first precharge node.