Datasheet

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LM3448
SNOSB51C –SEPTEMBER 2011–REVISED MAY 2013 www.ti.com
Figure 17. Voltage Waveforms After Bridge Rectifier Without TRIAC Dimming
Figure 18(b) and Figure 18(a) show typical TRIAC dimmed voltage waveforms before and after the bridge
rectifier.
Figure 18. Voltage Waveforms After Bridge Rectifier With TRIAC Dimming
SENSING THE RECTIFIED TRIAC WAVEFORM
An external series pass regulator (R2, D1, and Q1) translates the rectified line voltage to a level where it can be
sensed by the BLDR pin on the LM3448 as shown in Figure 19.
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