Abstract
Usually small and medium-sized Motors, transformers and other electrical appliances are used directly to start, that is motor rated voltage in the direct start. Directly activate the AC motor, the starting current, and rated current up to 5 ~ 7 times, resulting in motor windings due to excessive starting current over-heated, thus speeding up the aging of insulation, this will result in electricity supply networks, Result in reduced power supply network voltage is too large, such as the shortcomings. Switching power supply because of its high efficiency, large output current, static current, the advantages of small size in the hand-held devices and portable products are widely used, has become the main force of the AS IC power and a typical switching power supply in the boot process, easily lead to surge current and cause the output voltage overshoot may cause damage to electronic systems, so the need for soft-start circuit. In this paper, several soft-start circuit of the features and functionality, in line with the Bearing processing, select a switch circuit with soft-start circuit, in order to enable a smooth start-up heater and maintenance-free design with soft-start the load switch to achieve the protection of energy-saving control.
