A magnetic random access memory (MRAM) sense amplifier circuit is provided that includes a pre-amplifier circuit that includes a data leg, a reference leg, and an operational amplifier. The data leg includes a first P-channel transistor and a first N-channel transistor that receives a local data bit bias voltage and outputs a data branch output voltage. The reference leg includes a second P-channel transistor and a second N-channel transistor. The transistors of the reference leg mismatch the transistors of the data leg due to device variations. The second N-channel transistor receives a global reference bit bias voltage, and outputs a reference voltage. The operational amplifier determines the difference between the data branch output voltage and the reference voltage, and generates an adjusted local data bit bias voltage that matches the global reference bit bias voltage to offset the mismatches that exist between the data leg and the reference leg.