UCC28950_13 Datasheet, PDF (8/11 Pages) Texas Instruments – Frequency Dithering With the UCC28950 and TLV3201

SLUA646 – May 2012
Here in Figure 6 the slight frequency variation of the outputs, and thus the main internal oscillator,
can be observed. If we were to view different single captures of these signals, the frequency would
be different each time. This can be observed in Figures 7 and 8. The frequency is varying both
above and below the 133kHz center frequency.
Figure 7. Two Output Signals of the UCC28950 with dithering added (single capture = ~ 122kHz)
Ch2 = OUTA Signal of controller
Ch3 = OUTB Signal of controller
Figure 8. Two Output Signals of the UCC28950 with dithering added (single capture = 144kHz)
Ch2 = OUTA Signal of controller
Ch3 = OUTB Signal of controller
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Frequency Dithering With the UCC28950 and TLV3201