IC AMP AUDIO PWR 1.2W MONO 8MSOP

TS4990IST

Manufacturer Part NumberTS4990IST
DescriptionIC AMP AUDIO PWR 1.2W MONO 8MSOP
ManufacturerSTMicroelectronics
TypeClass AB
TS4990IST datasheet
 

Specifications of TS4990IST

Output Type1-Channel (Mono)Max Output Power X Channels @ Load1.2W x 1 @ 8 Ohm
Voltage - Supply2.2 V ~ 5.5 VFeaturesDepop, Differential Inputs, Standby, Thermal Protection
Mounting TypeSurface MountPackage / Case8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
For Use With497-6383 - BOARD DEMO FOR TS4990Lead Free Status / RoHS StatusLead free / RoHS Compliant
Other names497-4451-2  
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Application information
Therefore, the power dissipated by each amplifier is:
P
= P
diss
supply
and the maximum value is obtained when:
and its value is:
Note:
This maximum value is only dependent on power supply voltage and load values.
The efficiency is the ratio between the output power and the power supply:
The maximum theoretical value is reached when V
4.5
Decoupling of the circuit
Two capacitors are needed to correctly bypass the TS4990: a power supply bypass
capacitor C
and a bias voltage bypass capacitor C
s
C
has particular influence on the THD+N in the high frequency region (above 7 kHz) and
s
an indirect influence on power supply disturbances. With a value for C
expect THD+N levels similar to those shown in the datasheet.
In the high frequency region, if C
on the power supply rail are less filtered.
On the other hand, if C
more filtered.
C
has an influence on THD+N at lower frequencies, but its function is critical to the final
b
result of PSRR (with input grounded and in the lower frequency region).
If C
is lower than 1 µF, THD+N increases at lower frequencies and PSRR worsens.
b
If C
is higher than 1 µF, the benefit on THD+N at lower frequencies is small, but the benefit
b
to PSRR is substantial.
Note that C
has a non-negligible effect on PSRR at lower frequencies. The lower the value
in
of C
, the higher the PSRR.
in
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- P
(W)
out
2 2V
---------------------- P
P
=
diss
π R
δP
diss
----------------- - = 0
δP
out
2
2V
CC
P
-------------- -
=
diss
2
π
max
R
L
P
out
η =
------------------ - =
P
supply
π
---- - = 78.5%
4
is lower than 1 µF, it increases THD+N and disturbances
s
is higher than 1 µF, those disturbances on the power supply rail are
s
CC
P
out
out
L
(W)
πV
PEAK
---------------------- -
4V
CC
= V
, so:
PEAK
CC
.
b
of 1 µF, you can
s
TS4990