TS4962M_07 STMICROELECTRONICS [STMicroelectronics], TS4962M_07 Datasheet - Page 28

• Manufacturer Part Number: TS4962M_07
• Description: 3W filter-free class D audio power amplifier
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Application information
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5.1
5.2
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Application information
Differential configuration principle
The TS4962M is a monolithic fully-differential input/output class D power amplifier. The
TS4962M also includes a common-mode feedback loop that controls the output bias value
to average it at V
always have a maximum output voltage swing, and by consequence, maximizes the output
power. Moreover, as the load is connected differentially compared to a single-ended
topology, the output is four times higher for the same power supply voltage.
The advantages of a full-differential amplifier are:
●
●
●
●
●
The main disadvantage is:
●
Gain in typical application schematic
Typical differential applications are shown in
In the flat region of the frequency-response curve (no input coupling capacitor effect), the
differential gain is expressed by the relation:
with R
Due to the tolerance of the internal 150kΩ feedback resistor, the differential gain will be in
the range (no tolerance on R
High PSRR (power supply rejection ratio).
High common mode noise rejection.
Virtually zero pop without additional circuitry, giving a faster start-up time compared to
conventional single-ended input amplifiers.
Easier interfacing with differential output audio DAC.
No input coupling capacitors required due to common mode feedback loop.
As the differential function is directly linked to external resistor mismatching, paying
particular attention to this mismatching is mandatory in order to obtain the best
performance from the amplifier.
in
expressed in kΩ.
CC
/2 for any DC common mode input voltage. This allows the device to
in
):
A
V
diff
273
--------- - A
R
=
in
Out
------------------------------ -
≤
In
+
+
Figure 1 on page
V
–
–
diff
Out
In
≤
-
327
--------- -
R
-
in
=
300
--------- -
R
in
4.
TS4962M