1. A circuit comprising: a current generating circuit comprising: a first current mirror configured to generate a first current having a first current value, wherein the first current value is less than a value of a first cell current through a first reference cell and a first transistor having a gate terminal directly connected with a drain terminal, and the first current value is based on a first ratio of the first cell current to the first current; and a second current mirror configured to generate a second current having a second current value, wherein the second current value is less than a value of a second cell current through a second reference cell and a second transistor having a gate terminal directly connected with a drain terminal, and the second current value is based on a second ratio of the second cell current to the second current, wherein the current generating circuit is configured to generate a reference current having a reference current value based on the first current value and the second current value; and a sense amplifier configured to receive a third current having a third current value and generate a voltage output based on the reference current value and the third current value.