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pzl927o1r · Wysłany: Nie 4:37, 27 Mar 2011 Temat postu: High productivity design

In response to this target market, currently many major semiconductor manufacturers (including the world-renowned semiconductor manufacturers) have launched their own dimming LED ASIC, but because of the inherent light-emitting principle of LED current dimming LED ASIC available in the market are not yet the case very mature,[link widoczny dla zalogowanych], has its inherent problems, this article will be dimmer view of the current program to make a detailed analysis and present our solution based on MCU dimming.
1 LED light-emitting properties of new technology allows LED current to achieve high power levels, LED power to achieve 1W, and even some to 5W, luminous efficiency to achieve 60-85LM / W, this device is called bright LED LED ( HB-LED). Currently we are using LED lighting on the HB-LED,[link widoczny dla zalogowanych], the LED 1W generally choose the way through the series and parallel composition of high-power LED lights, especially the main series. This LED for 3.4V ± 2%, a forward current of 350mA or so.
The - curve shown in Figure 1.1. Figure 1.1 LED? Curve can be seen from Figure 1 that, when added to the voltage across the LED does not meet 3.4V before, with the increase. When added to the LED when the voltage reaches 3.4V,[link widoczny dla zalogowanych], the change is small, increasing the voltage across the LED will only increase the current flowing through the LED, thus changing the LED brightness,[link widoczny dla zalogowanych], LED increased until the maximum (350MA), LED to achieve maximum brightness. Which has been clamped in (3.4V) or so.