TDA8929T NXP Semiconductors, TDA8929T Datasheet - Page 17

• Manufacturer Part Number: TDA8929T
• Manufacturer: NXP Semiconductors

Specifications of TDA8929T

• Lead Free Status / Rohs Status: Compliant

Philips Semiconductors
15 TEST AND APPLICATION INFORMATION
15.1
The test diagram in Fig.10 can be used for stand alone
testing of the controller. Audio and mode input pins are
configured as in the application. For the simulation of a
switching output power stage a simple level shifter can be
used. It converts the digital PWM signal from the controller
(switching between V
PWM signal switching between V
A proposal for a simple level shifting circuit is given
in Fig.9.
2001 Dec 11
handbook, full pagewidth
Controller class-D audio amplifier
Test circuit
SS
and V
0/12 V
switch
V SS
SS
+ 12 V level) to a
DD
and V
20 k
5 V
SS
.
10 k
Fig.9 Level shifter.
74LV14
1.33 k
BST82
2 k
17
The low-pass filter performs the demodulation, so that the
audio signal can be measured with an audio analyzer. For
measuring low distortion values, the speed of the level
shifter is important. Special care has to be taken at a
sufficient supply decoupling and output waveforms without
ringing.
The handshake with the power stage is simulated by a
direct connection of the release inputs (REL1 and REL2)
with the switch outputs (SW1 and SW2) of the controller.
The enable outputs (EN1 and EN2) for waking-up the
power stage are not used here, only the output level and
timing are measured.
10 nF
10
10
PHC2300
MGW154
33
42
V DD
PWM
V SS
Preliminary specification
TDA8929T