TDA8933B NXP Semiconductors, TDA8933B Datasheet - Page 26

• Manufacturer Part Number: TDA8933B
• Description: The TDA8933B is a high-efficiency class D amplifier with low power dissipation
• Manufacturer: NXP Semiconductors

NXP Semiconductors
TDA8933B_1
Preliminary data sheet
14.6 Device synchronization
Where:
Example:
Substituting R1 = R2 = 4.7 k , Z
results in a gain of G
If two or more TDA8933B devices are used in one application it is recommended that all
the devices are synchronized at the same switching frequency to avoid beat tones. This
can be done by connecting all OSCIO pins together and configuring one of the devices as
master while the others are configured as slaves (see
A device is configured as master when a resistor R
and pin V
configured as an oscillator output for synchronization. The OSCREF pins of the slave
devices should be shorted to pin V
R
Fig 10. Master/slave concept in a two-chip application
•
•
•
•
•
EQ
R1 = series resistors (
R2 = series resistors (
R
R3 = parallel resistor (
Z
=
i
EQ
= internal input impedance (
----------------- -
R3
R3
= equivalent resistance (
SSD(HW)
+
Z
Z
i
i
100 nF
, thus setting the carrier frequency. Pin OSCIO of the master is then
C osc
v(tot)
master
Rev. 01 — 23 October 2008
OSCREF
= 26.3 dB.
R osc
39 k
TDA8933B
V
SSD(HW)
IC1
i
= 100 k and R3 = 22 k in
SSD(HW)
OSCIO
, configuring pin OSCIO as an input.
slave
osc
OSCIO
is connected between pin OSCREF
Figure
TDA8933B
V
SSD(HW)
IC2
10).
Equation 8
Class D audio amplifier
OSCREF
010aaa138
TDA8933B
© NXP B.V. 2008. All rights reserved.
and
Equation 9
26 of 42
(9)