Design of a power supply protection circuit with EMI suppression function

Abstract

Non cooled infrared thermal imaging cameras require external DC power supply. In practical applications, there may be abnormal situations where the power supply is reversed, and the actual power supply voltage exceeds or falls below the required voltage of the camera [1] . Traditional camera power modules do not have protective circuits or power noise suppression functions, which can cause camera damage and a decrease in infrared imaging quality.In response to this issue, this article proposes a circuit design based on the ADI power management chip LTC4365ITS8 # TRMPBF, which integrates EMI suppression, under-voltage, over-voltage, and power reverse protection functions, and has a light alarm function.Example verification and analysis show that the circuit suppresses common mode interference and serial mode interference from external switching power supplies, and improves the quality of infrared images;When there is an abnormal power supply as mentioned above, the protection circuit module will stop supplying power to the subsequent modules, protect the components of the subsequent modules from damage, and emit a light alarm [2] .