Ultra Low Input Current Consumption Power Supplies under No-Load Condition for Discontinuous Transmission Systems

The present paper focuses on power supplies for communication system devices with discontinuous transmission. The paper studies and analyzes power supplies with high efficiency and low quiescent current consumption under no- load conditions. Linear and switched power supplies with and without isolation are being considered and the trade-offs of different topologies are presented. Finally it recommends solutions for wireless communication applications. To check the conclusions of the study, a practical implementation of an isolated switched power supply for wireless devices is presented, with one of the lowest quiescent current consumptions in the market The practical design reaches the technology limits of the isolated power supplies under no-load conditions. The design has been implemented on a commercial wireless device. This device has three communication modules; EGSM, WiFi™ and ZigBee™, and it is intended for the remote control of electromechanical actuators and electronic sensors in harsh environment applications.