Philips TDA1562Q - Page 25

Philips Semiconductors
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TDA1562Q application note
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©
Koninklijke Philips Electronics N.V.
2004
. All rights reserved.
Application note Rev. 01.02 — 05 May 2006 25 of 62
Fig. 4 shows the situation at a moderate output level (approx. 40W). The sine wave is not
clipping yet. The voltage across the lift capacitor is shown for the positive output so
during the positive half of the sinewave, Vlift drops and it is visible that current is drawn
from the lift capacitor (Icharge going negative). During the negative half of the sinewave,
the lift capacitor is recharged.
Fig 12. Charge current, output signal and lift capacitor voltage at Po=40W, f=30Hz
Vlift
I charge
Vout
I audio
(fig 2b)
IClift