STEVAL-CCA019V1 STMicroelectronics, STEVAL-CCA019V1 Datasheet - Page 22

• Manufacturer Part Number: STEVAL-CCA019V1
• Description: BOARD EVAL AUDIO AMP FOR TS4982
• Manufacturer: STMicroelectronics

Specifications of STEVAL-CCA019V1

• Amplifier Type: Class AB
• Output Type: 2-Channel (Stereo) with Stereo Headphones
• Max Output Power X Channels @ Load: 2W x 2 @ 4 Ohm; 125mW x 2 @ 16 Ohm
• Voltage - Supply: 5.0V
• Operating Temperature: -40°C ~ 85°C
• Board Type: Fully Populated
• Utilized Ic / Part: TS4982
• Description/function: Audio Amplifiers
• Operating Supply Voltage: 5 V
• Output Power: 2 W
• Product: Audio Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: TS4982
• Other names: 497-10339

Application information
4.8
4.8.1
22/31
Decoupling and charge pump capacitors
Only a power supply decoupling capacitor Cs and a bias voltage decoupling capacitor Cb
are needed to correctly decouple the TS4982.
Decoupling capacitors Cs and Cb
Cs has a particular influence on the THD+N in the high frequency region (above 7 kHz) and
an indirect influence on the power supply disturbances. With a value for Cs of 1 µF, you can
expect similar THD+N performances to those outlined in this document (see
Figure
●
●
Cb has a critical influence on the final result of the PSRR with input grounded and in the
lower frequency region in the following manner:
●
●
Figure 43. PSRR vs. frequency
In the high frequency region, if Cs is lower than 1 µF, it increases THD+N and
disturbances on the power supply rail are less filtered.
On the other hand, if Cs is higher than 1 µF, those disturbances on the power supply
rail are more filtered.
If Cb is lower than 1 µF the PSRR performance worsens at lower frequencies.
If Cb is higher than 1 µF, the benefit to PSRR is decreased significantly.
23). For example:
-100
-120
-20
-40
-60
-80
0
20
SPEAKER
V
R
Inputs AC grounded
CC
L
Doc ID 14527 Rev 2
≥
= PV
4
Ω ,
Cb = 1
CCL,R
Cin = 1
100
= 5V, Vripple = 200mV
μ
F
μ
F, T
AMB
Frequency (Hz)
= 25
Cb = 470nF
°
C, Gain = 9dB
1k
PP
Cb = 2.2
10k
μ
F
20k
Figure 12
TS4982
to