Datasheet

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_
+
IN-
IN+
PWM H-
Bridge
V
O+
V
O-
Internal
Oscillator
C
S
To Battery
V
DD
GND
Bias
Circuitry
R
I
R
I
Differential
Input
TPA2010D1
Filter-Free Class D
SHUTDOWN
C
I
C
I
_
+
IN-
IN+
PWM H-
Bridge
V
O+
V
O-
Internal
Oscillator
C
S
To Battery
V
DD
GND
Bias
Circuitry
R
I
R
I
Single-ended
Input
TPA2010D1
Filter-Free Class D
SHUTDOWN
C
I
C
I
SUMMING INPUT SIGNALS WITH THE TPA2010D1
Summing Two Differential Input Signals
Gain 1 +
V
O
V
I1
+
2 x 150 kW
R
I1
ǒ
V
V
Ǔ
(4)
Gain 2 +
V
O
V
I2
+
2 x 150 kW
R
I2
ǒ
V
V
Ǔ
(5)
TPA2010D1
SLOS417C – OCTOBER 2003 – REVISED SEPTEMBER 2007
Figure 28. TPA2010D1 Application Schematic With Differential Input and Input Capacitors
Figure 29. TPA2010D1 Application Schematic With Single-Ended Input
Most wireless phones or PDAs need to sum signals at the audio power amplifier or just have two signal sources
that need separate gain. The TPA2010D1 makes it easy to sum signals or use separate signal sources with
different gains. Many phones now use the same speaker for the earpiece and ringer, where the wireless phone
would require a much lower gain for the phone earpiece than for the ringer. PDAs and phones that have stereo
headphones require summing of the right and left channels to output the stereo signal to the mono speaker.
Two extra resistors are needed for summing differential signals (a total of 5 components). The gain for each input
source can be set independently (see Equation 4 and Equation 5 , and Figure 30 ).
If summing left and right inputs with a gain of 1 V/V, use R
I1
= R
I2
= 300 k Ω .
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Product Folder Link(s): TPA2010D1