歡迎進入福州萊格光電科技有限公司官網!

186-5078-8929
欄目導航
新聞動態
聯系我們
服務熱線
186-5078-8929
手機: 186-5078-8929
郵箱: cdlkimi@163.com
地址: 福州市晉安區新店鎮西園692區
當前位置:主頁 > 新聞動態
LED燈閃爍的常見原因與處理辦法
瀏覽:296 發布日期:2017-05-04
Generally, the human eye can detect light flashes with frequencies up to 70 Hz, which are not sensed above this frequency. Therefore, in LED lighting applications, if the pulse frequency appears below 70 Hz low-frequency components, the human eye will feel flashing. Of course, in specific applications, there are a variety of factors that may cause LED lights to flicker. For example, in offline low power LED lighting applications, a common power topology is an isolated flyback topology. In the off-line 8W LED driver GreenPoint&reg with solid state lighting standard energy star; reference design as an example, the sine wave regulator side flyback power conversion does not provide constant energy to the primary bias, dynamic self supply (DSS) circuit may activate and trigger light flashes. To avoid this problem, it is necessary to allow primary bias to be discharged at each half cycle, and accordingly, the values of the capacitance and resistance that constitute the bias circuit need to be appropriately chosen.
In addition, electromagnetic interference (EMI) filters are also required, even in LED drive applications that provide excellent power factor correction and support TRIAC dimming. The transient current caused by the TRIAC step (step) will excite the natural resonance of the inductance and capacitance in the EMI filter. If this resonant characteristic causes the input current to fall below the TRIAC sustaining current, the TRIAC will turn off. After a short delay, the TRIAC usually switches on and fires the same resonance. In the 1.5 cycle of the input power waveform, this series of events may be repeated several times to form visible LED flashes. To cope with this problem, a key requirement of TRIAC dimming is that the input capacitance of the EMI filter is very low and that the capacitor is decoupled through the TRIAC and the winding impedance. According to the formula, if the capacitance of the dimming module is reduced, the resistance of the resonant circuit can be increased, and the oscillation is suppressed in principle, and the desired circuit work is resumed.

长途汽车上玩弄少妇,上课被同桌取下小内裤玩流水,日本熟妇浓毛护士