| 摘要 |
FIELD: electricity.SUBSTANCE: suggested invention refers to the sphere of artificial lighting control and regulation using powerful light-emitting diodes (LEDs) supplied from external direct current sources. Technical result consists in increase of LEDs service life and accuracy of current regulation due to regulation against average current, and it is attained due to generation of a pulse-width modulated signal controlling the built-in transistor switch by integration of a signal from the current sensor and its comparison with synchronous saw-tooth voltage, wherein RS-trigger, logic elements and a source of reference thermostable voltage is used in order to ensure protection from reduction of input voltage, short-circuiting current and overheating of the elements. The device checking has been made by simulation modelling in OrCAD environment and by experimental measurements. Results of the investigations demonstrated that the suggested device allows increase in current stabilisation accuracy up to 3%, linearity of specifications and reproducibility of the current source for LEDs, usage of lower inductances (50-500 mcH) and ability of dimming by external signal. In case of breakdown of one of light emitters the remaining LEDs will continue functioning with the specific current value.EFFECT: advantage of this device is high current stability, which prevents overloading of any LED in a succession and ensures large service life.6 dwg |
