A Precise and High Linearity Power Supply Noise Monitor Circuit

In this paper, we proposed a new power supply noise monitor with high linearity in CMOS 0.18um process.We remove the pre charging capacitor from power supply noise monitor circuit and add an independent stable charging voltage source to enhance power supply noise detection linearity. We set the detection path with a higher supply voltage of 2.5V to turn on the detection circuitry immediately when supply voltage drops. In this way, the noise detection range can be enlarged and the noise detection accuracy is improved by 4.94 times. By removing the pre charging capacitor we can save approximately 40% area as compare with the original design.