TS4997IQT STMicroelectronics, TS4997IQT Datasheet - Page 22

• Manufacturer Part Number: TS4997IQT
• Description: IC AMP AUDIO 1W STER AB 16QFN
• Manufacturer: STMicroelectronics
• Type: Class ABr

Specifications of TS4997IQT

• Output Type: 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 1W x 2 @ 8 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: 3D, Depop, Differential Inputs, Standby, Thermal Protection
• Mounting Type: Surface Mount
• Package / Case: 16-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-5995-2

Application information
4.5
4.6
22/34
Low frequency response
The input coupling capacitors block the DC part of the input signal at the amplifier inputs. In
the low frequency region, C
pass filter with a -3dB cut-off frequency.
with R
So, for a desired -3dB cut-off frequency we can calculate C
From
for some typical cases.
Figure 64. -3dB lower cut-off frequency vs. input capacitance
3D effect enhancement
The TS4997 features 3D audio effect which can be programmed at three discrete levels
(LOW, MEDIUM, HIGH) through input pins 3D1 and 3D0 which provide a digital interface.
The correspondence between the logic levels of this interface and 3D effect levels are
shown in
The 3D audio effect applied to stereo audio signals evokes perception of spatial hearing and
improves this effect in cases where the stereo speakers are too close to each other, such as
in small handheld devices, or mobile equipment.
The perceived amount of 3D effect is also dependent on many factors such as speaker
position, distance between speakers and listener, frequency spectrum of audio signal, or
difference of signal between left and right channel. In some cases, the volume can increase
when switching on the 3D effect. This factor is dependent on the composition of the stereo
audio signal and its frequency spectrum.
Figure
IN
expressed in Ω and C
Table
64, you can easily establish the C
9.
100
10
0.1
IN
Rin=12k
G~12dB
starts to have an effect. C
IN
F
expressed in F.
C
CL
IN
Ω
=
=
0.2
Input Capacitor Cin (
---------------------------------------------- - Hz
2
----------------------------------------------- - F ( )
2
Rin=24k
G~6dB
×
×
π
π
×
×
R
IN
1
R
1
IN
Ω
IN
value required for a -3 dB cut-off frequency
×
×
C
0.4
F
IN
CL
(
IN
Rin=6.2k
G~18dB
μ
F)
and R
)
IN
0.6
:
Tamb=25
IN
Ω
form a first-order high
0.8
°
C
1
TS4997