A method of writing in and reading a memory device comprising a plurality of magnetoresistive random access memory (MRAM) cells arranged in rows and columns, each MRAM cell to be written by using a thermally-assisted switching write operation, including a magnetic tunnel junction having a resistance that can be varied during a write operation when the magnetic tunnel junction is heated at a high threshold temperature, and a select transistor electrically coupled to the magnetic tunnel junction; a plurality of word lines connecting MRAM cells along a row via the gate of the select transistor; a plurality of bit lines connecting MRAM cells along a column; and a plurality of source lines arranged substantially orthogonal with the bit lines and connecting the MRAM cells along a row via the drain of the select transistor; the method comprising, during the write operation: supplying a bit line voltage (V BL) to one of the bit lines and a word line voltage (V WL) to one of the word lines for passing a heating current (I heat) through the magnetic tunnel junction of a selected MRAM cell; once the magnetic tunnel junction has reached the high threshold temperature, varying the resistance of the magnetic tunnel junction; cooling the magnetic tunnel junction such as to freeze said resistance in its written value; and wherein said word line voltage (V WL) is a word line overdrive voltage (V WLo) being higher than the core operating voltage of the MRAM cells; such that the heating current (I heat) has a magnitude that is high enough for heating the magnetic tunnel junction at the predetermined high threshold temperature and during a read operation: measuring the resistance of the magnetic tunnel junction; characterized in that the method further comprises during the write operation, supplying a source line overdrive voltage (V SLo) to the source line; and during the read operation, supplying to the source line the source line overdrive voltage (V SLo) that is the same as the source line overdrive voltage supplied to the source line during the write operation. supplying a bit line voltage (V BL) to one of the bit lines and a word line voltage (V WL) to one of the word lines for passing a heating current (I heat) through the magnetic tunnel junction of a selected MRAM cell; once the magnetic tunnel junction has reached the high threshold temperature, varying the resistance of the magnetic tunnel junction; cooling the magnetic tunnel junction such as to freeze said resistance in its written value; and wherein said word line voltage (V WL) is a word line overdrive voltage (V WLo) being higher than the core operating voltage of the MRAM cells; such that the heating current (I heat) has a magnitude that is high enough for heating the magnetic tunnel junction at the predetermined high threshold temperature and during a read operation: measuring the resistance of the magnetic tunnel junction; characterized in that the method further comprises during the write operation, supplying a source line overdrive voltage (V SLo) to the source line; and during the read operation, supplying to the source line the source line overdrive voltage (V SLo) that is the same as the source line overdrive voltage supplied to the source line during the write operation. measuring the resistance of the magnetic tunnel junction; characterized in that the method further comprises during the write operation, supplying a source line overdrive voltage (V SLo) to the source line; and during the read operation, supplying to the source line the source line overdrive voltage (V SLo) that is the same as the source line overdrive voltage supplied to the source line during the write operation.