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TDA8932B Datasheet, PDF (22/48 Pages) NXP Semiconductors – Class-D audio amplifier | |||
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NXP Semiconductors
TDA8932B
Class-D audio ampliï¬er
14. Application information
14.1 Output power estimation
The output power Po at THD+N = 0.5 %, just before clipping, for the SE and BTL
conï¬guration can be estimated using Equation 2 and Equation 3.
SE conï¬guration:
Po(0.5%) = ---ï£ï£«----R--------L--------+----------R-------D--------S-----o-----n-R-------+-L---------R--------s------+----------R--------E------S-----8R------Ã---Ã--R--(--L-1----â-----t--w---(--m----i-n---)---Ã------f--o---s--c--)----Ã----V-----P------2
(2)
BTL conï¬guration:
Po(0.5%) = ---ï£ï£«----R--------L--------+---------2----------Ã---------(----R-R------L--D-------S-----o------n-------+----------R--------s-----)-2-----ÃÃ----R-(--1-L----â----t--w----(-m----i--n--)---Ã------f---o--s--c---)---Ã-----V----P------2
(3)
Where:
VP = supply voltage VDDP1 â VSSP1 (V) or VDDP2 â VSSP2 (V)
RL = load impedance (â¦)
RDSon = on-resistance power switch (â¦)
Rs = series resistance output inductor (â¦)
RESR = equivalent series resistance SE capacitor (â¦)
tw(min) = minimum pulse width (s); 80 ns typical
fosc = oscillator frequency (Hz); 320 kHz typical with Rosc = 39 kâ¦
The output power Po at THD+N = 10 % can be estimated by:
Po(10%) = 1.25 Ã Po(0.5%)
(4)
Figure 8 and Figure 9 show the estimated output power at THD+N = 0.5 % and
THD+N = 10 % as a function of the supply voltage for SE and BTL conï¬gurations at
different load impedances. The output power is calculated with: RDSon = 0.15 ⦠(at
Tj = 25 °C), Rs = 0.05 â¦, RESR = 0.05 ⦠and IO(ocp) = 4 A (minimum).
TDA8932B_4
Product data sheet
Rev. 04 â 18 December 2008
© NXP B.V. 2008. All rights reserved.
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