Micro-Satellites ,consist of many controllers, controlling circuits, sensors, actuators, telemetric equipment, data acquisition systems and storage systems to monitor and control the satellite operations. These have different power requirements and must be turned ON or OFF depending upon the satellite operation for better utilization of the electrical energy available in limit. These functions are fulfilled by the Power Conditioning Unit (PCU) present on each of the above mentioned circuits. PCUalso protects these devices from faults such as short circuit, open circuit, over current and over temperature, gives feedback of ON/OFF status and fault status to the on board Microcontroller (µC) in regular intervals thereby forming a close loop system. As it is a Micro-Satellite, PCU design must be compact and must use as few components as possible to make it less bulky without compromising on its objectives. This paper describes PCU, its objectives,different architectures of PCU depending on number of loads and operational speed requirements, how the objectives of PCU and its design are achieved, devices used in the designs and different protocols used for communication.

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Micro-satellites Power Conditioning Unit (pcu) I2c Communication Protocol 1-wire Communication Protocol Electrical And Addressable Switch