4-Mb magnetoresistive random access memory (MRAM) with a novel magnetic bit cell and toggle switching mode is presented. The circuit was designed in a five level metal, 0.18-mum complementary metal-oxide-semiconductor process with a bit cell size of 1.55 mum(2). The new bit cell uses a balanced synthetic antiferromagnetic free layer and a phased write pulse sequence to provide robust switching performance with immunity from half-select disturbs. This switching mode greatly improves the operational performance of the MRAM as compared to conventional MRAM. A detailed description of this 4-Mb toggle MRAM is presented.