| 摘要 |
A power supply system and corresponding methodology is provided for providing a self-protected power supply for use with electronic electricity meters. The self-protecting features are provided, in part, through the use of surface mounted resistive components corresponding to a resistor dropper portion of the power supply. The use of surface mount components also provides a general reduction in circuit board surface area requirements thereby providing a compact overall construction and provides economies with respect to reduction in manufacturing process steps. When the surface mount resistor divider is configured along with a half-wave rectifier, a low voltage DC supply is obtained from a direct connection to a much higher voltage AC mains source without requiring the use of coupling capacitors or transformers. Plural output voltages may be provided and capacitive filtering may be associated with the outputs. The use of a surface mount resistor divider in combination with surge protection elements helps to distribute any power surge over the power supply, which facilitates the use of less robust surge protection devices to achieve desired levels of protection.
|
