2003 Mar 20
28
Philips Semiconductors
Objective specification
2
×
25 W class-D power amplifier
TDA8922
handbook, halfpage
Vres(rms)
(mV)
100
400
200
500
600
fclk (kHz)
300
0
1000
600
800
200
400
MGX345
Fig.34 PWM residual voltage as a function of clock
frequency.
V
P
=
±
20 V; R
L
= 8
Ω
.
handbook, halfpage
Po
(W)
100
400
200
500
600
fclk (kHz)
300
0
50
30
40
10
20
MGX343
Fig.35 Output power as a function of clock
frequency.
V
P
=
±
20 V; R
L
= 8
Ω
; f
i
= 1 kHz; THD + N = 10%.
handbook, halfpage
MGX348
Vo
(V)
10
−
4
10
−
1
10
−
5
10
−
6
10
−
3
10
−
2
1
10
VMODE (V)
6
5
4
3
2
1
0
Fig.36 Output voltage as a function of mode
selection voltage.
V
i
= 100 mV; f
i
= 1 kHz.
handbook, halfpage
MGX349
S/N
(dB)
40
80
20
0
60
100
120
Po (W)
10
−
2
10
−
1
1
10
10
3
10
2
(1)
(2)
Fig.36 Signal-to-noise ratio as a function of output
power.
V
P
=
±
20 V; R
s
= 5.6 k
Ω
.; filter: 20 kHz AES17
(1) 2
×
8
Ω
SE.
(2) 1
×
8
Ω
BTL.
