一种面向MRAM感测放大器的三级运算放大器设计OA

In order to meet the requirements for amplifying weak storage signals in complex battlefield elec-tromagnetic environments,a highly reliable sensing amplifier for magnetic random access memory(MRAM)stor-age arrays is designed.First,the sensing amplifier circuit is analyzed;then the damping factor controlled frequen-cy compensation(DFCFC)technology is introduced to optimize the frequency response characteristics,and finally,the circuit is simulated based on the SMIC 0.18 μm technology.The simulation results show that under the conditions of a 1.8 V power supply voltage and a 10 pF capacitive load,the direct current open-loop gain of this amplifier reaches 137.38 dB,with the unit gain bandwidth of 36 MHz,and the phase margin of 74.07°,and that compared with the three common sensing amplifiers,the sensing amplifier designed in this paper has better performance.