TS4871 ST Microelectronics, Inc., TS4871 Datasheet - Page 23

• Manufacturer Part Number: TS4871
• Description: 1W Mono Audio Amplifier With Standby Active High
• Manufacturer: ST Microelectronics, Inc.

which gives 16Hz.
In Higher frequency we want 20kHz (-3dB cut off
frequency). The Gain Bandwidth Product of the
TS4871 is 2MHz typical and doesn’t change when
the amplifier delivers power into the load.
The first amplifier has a gain of:
and the theoretical value of the -3dB cut-off higher
frequency is 2MHz/3 = 660kHz.
We can keep this value or limit the bandwidth by
adding a capacitor Cfeed, in parallel on Rfeed.
Then:
So, we could use for Cfeed a 220pF capacitor
value that gives 24kHz.
Now, we can calculate the value of Cb with the
formula b = 50k xCb >> in = (Rin+Rfeed)xCin
which permits to reduce the pop and click effects.
Then Cb >> 0.8µF.
We can choose for Cb a normalized value of 2.2µF
that gives good results in THD+N and PSRR.
In the following tables, you could find three
another examples with values required for the
demoboard.
Remark : components with (*) marking are
optional.
C
C
FE E D
IN
=
=
----------------------------- - = 795nF
2
-------------------------------------- - = 265pF
2
Rfee d
----------------- = 3
RinF
R in
1
R
F E E D
1
C L
F
C H
Application n°1 : 20Hz to 20kHz bandwidth and
6dB gain BTL power amplifier.
Components :
Application n°2 : 20Hz to 20kHz bandwidth and
20dB gain BTL power amplifier.
Components :
R1
R4
R6
R7
R8*
C5
C6
C7
C9
C10
C12
S1, S2, S6, S7
S8
P1
D1*
U1
R1
R4
R6
R7
R8*
C5
C6
C7
Designator
Designator
22k / 0.125W
22k / 0.125W
Short Cicuit
330k / 0.125W
(Vcc-Vf_led)/If_led
470nF
100µF
100nF
Short Circuit
Short Circuit
1µF
2mm insulated Plug
10.16mm pitch
3 pts connector 2.54mm
pitch
PCB Phono Jack
Led 3mm
TS4871ID or TS4871IS
110k / 0.125W
22k / 0.125W
Short Cicuit
330k / 0.125W
(Vcc-Vf_led)/If_led
470nF
100µF
100nF
Part Type
Part Type
TS4871
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