TDA7491P13TR STMicroelectronics, TDA7491P13TR Datasheet - Page 34

• Manufacturer Part Number: TDA7491P13TR
• Description: AMP, AUDIO, DUAL, CLASS D, 36PSSOEPD
• Manufacturer: STMicroelectronics

Specifications of TDA7491P13TR

• Amplifier Class: D
• No. Of Channels: 2
• Output Power: 9.5W
• Supply Voltage Range: 5V To 18V
• Thd + N: 0.1% @ 1W, 6ohm, VCC=11V
• Load Impedance: 6ohm
• Operating Temperature Range: 0°C To +70°C
• Rohs Compliant: Yes

Applications information
7.4
7.4.1
7.4.2
34/40
Internal and external clocks
The clock of the class-D amplifier can be generated internally or can be driven by an
external source.
If two or more class-D amplifiers are used in the same system, it is recommended that all
devices operate at the same clock frequency. This can be implemented by using one
TDA7491P as master clock, while the other devices are in slave mode (that is, externally
clocked. The clock interconnect is via pin SYNCLK of each device. As explained below,
SYNCLK is an output in master mode and an input in slave mode.
Master mode (internal clock)
Using the internal oscillator, the output switching frequency, f
resistor, R
where R
In master mode, pin SYNCLK is used as a clock output pin, whose frequency is:
For master mode to operate correctly then resistor R
below in
Slave mode (external clock)
In order to accept an external clock input the pin ROSC must be left open, that is, floating.
This forces pin SYNCLK to be internally configured as an input as given in
The output switching frequency of the slave devices is:
Table 9.
Figure 53. Master and slave connection
Master
Slave
f
f
f
SW
SYNCLK
SW
OSC
= 10
Table
= f
OSC
SYNCLK
Mode
How to set up SYNCLK
is in kΩ.
= 2 * f
6
, connected to pin ROSC:
Cosc
100 nF
9.
/ ((16 * R
SW
/ 2
ROSC
OSC
TDA7491P
Master
Rosc
39 kΩ
+ 182) * 4) kHz
Doc ID 13540 Rev 4
R
Floating (not connected)
OSC
SYNCLK
< 60 kΩ
Output
ROSC
OSC
SYNCLK
must be less than 60 kΩ as given
TDA7491P
Input
SW
Output
Input
Slave
, is controlled by the
ROSC
SYNCLK
Table
TDA7491P
9.