AW8155B
Jul. 2022 V1.3
www.awinic.com
21
COPYRIGHT ©2022 SHANGHAI AWINIC TECHNOLOGY CO. LTD.
Applications Information
Supply Decoupling Capacitor
（
C
S
）
The AW8155B is a high-performance audio amplifier that requires adequate power supply decoupling. For
higher frequency transients, a good low equivalent-series-
resistance (ESR) ceramic capacitor, typically 1μF,
placed as close as possible to the device VDD pin works best. For filtering lower-frequency noise signals, a
10 μF or greater capacitor placed near the audio power amplifier would also help.
Input Capacitor
The input coupling capacitor blocks the DC voltage at the amplifier input terminal. The input capacitors and
internal
input
resistors
(28.5
KΩ) form a high-pass filter with the corner frequency, fc.
Hz
169
RinCin
2
1
f
C
=
=
.
Setting the high-pass filter point high can block the 217Hz GSM noise coupled to inputs. Better matching of
the input capacitors improves performance of the circuit and also help to suppress pop-click noise.
Cin
33nF
Differential
Input
Cin
33nF
INP
INN
Figure 17.
Differential Input
Cin
33nF
Single-Ended
Input
Cin
33nF
INP
INN
Figure 18.
Single-Ended Input
Ferrite Chip Bead and Capacitor
The AW8155B passed FCC and CE radiated emissions with no ferrite chip beads and capacitors with speaker
trace wires 24 inch.Use ferrite chip beads and capacitors if device near the EMI sensitive circuits and/or there
are long leads from amplifier to speaker, placed as close as possible to the output pin.
Ferrite
Chip Bead
0.1nF
0.1nF
VOP
VON
Ferrite
Chip Bead
Figure 19.
Ferrite Chip Bead and capacitor
awinic Confidential
