TS4974_07 STMICROELECTRONICS [STMicroelectronics], TS4974_07 Datasheet - Page 20

• Manufacturer Part Number: TS4974_07
• Description: 1W differential audio power amplifier with up/down digital volume control pins
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Application information
4.7
4.8
4.9
20/25
Pop performance
Due to its fully differential structure, the pop performance of the TS4974 is close to perfect.
However, due to mismatching between internal resistors R
capacitors C
components, the TS4974 includes pop reduction circuitry. With this circuitry, the TS4974 is
close to zero pop for all possible common applications.
In addition, when the TS4974 is in standby mode, due to the high impedance output stage in
this configuration, no pop is heard.
Single-ended input configuration
It is possible to use the TS4974 in a single-ended input configuration. The schematic in
Figure 41
Figure 41. Typical single-ended input application
Volume setting
The TS4974 features a digital volume control with an internal gain range of -33 dB up to
+12 dB, by steps of 3 dB. When the device is powered up from V
standby pin), an initial gain of -12dB is internally fixed. When standby mode is activated, the
gain value is memorized and held until standby is released.
shows an example of this configuration.
Vin
in
, some noise might remain at startup. To eliminate the effect of mismatched
P1
Cin1
330nF
Cin2
330nF
Volume DOWN
Volume UP
Cb
1µF
1
2
3
TS4974 DFN10
U1
Vin-
Vin+
BYP ASS
S1
S2
DIGITAL VOLUME
VCC
CONTROL
Rpu1
470k
STBY control
BIAS
STBY
VCC
STBY
Rpu2
470k
Rpd1
470k
Rpd1
470k
+
VCC
in
, R
feed
Vout+
CC
Vout-
, and external input
Cs
1µF
(and not from the
9
8
Speaker
8 Ohms
TS4974