TDA8929T Datasheet, PDF (19/36 Pages) NXP Semiconductors – Controller class-D audio amplifier

Philips Semiconductors
Controller class-D audio amplifier
Preliminary specification
TDA8929T
15.2 BTL application
When using the system in a mono BTL application (for
more output power), the inputs of both channels must be
connected in parallel. The phase of one the inputs must be
inverted (see Fig.5). In principle the loudspeaker can be
connected between the outputs of the two single-ended
demodulation filters. For improving the common mode
behavior of the filter, the configuration in Fig.12 is advised.
15.3 Mode pin
For correct operation the switching voltage on pin MODE
should be de-bounced. If this pin is driven by a mechanical
switch an appropriate de-bouncing low-pass filter should
be used. If pin MODE is driven by an electronic circuit or
microcontroller then it should remain, for at least 100 ms,
at the mute voltage level (V_th1+) before switching back to
the standby voltage level.
15.4 External clock
Figure 11 shows an external clock oscillator circuit.
15.5 Reference designs
The reference design for a two-chip class-D audio
amplifier for TDA8926J or TDA8927J and TDA8929T is
shown in Fig.12. The Printed-Circuit Board (PCB) layout is
shown in Fig.13. The bill of materials is given in Table 1.
The reference design for a two-chip class-D audio
amplifier for TDA8926TH or TDA8927TH and TDA8929T
is shown in Fig.14. The PCB layout is shown in Fig.15.
handbook, full pagewidth
120 pF C3
1
R1
2
9.1 kΩ
3
J1
14
13
12
4 HEF4047B 11
5
10
6
9
7
8
external clock
VDDA
R19
5 kΩ
mode select
R20
39 kΩ
on
S1
mute
off
MODE
6
D1
5V6
C44
220 nF
TDA8929T
GND
OSC
7
MGW155
Fig.11 External oscillator circuit.
2001 Dec 11
19