TS4994EIKJT STMICROELECTRONICS [STMicroelectronics], TS4994EIKJT Datasheet - Page 29

• Manufacturer Part Number: TS4994EIKJT
• Description: 1.2 W differential input/output audio power amplifier with selectable standby
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

TS4994FC
Note:
and
Therefore, the average current delivered by the supply voltage is:
Equation 1
The power delivered by the supply voltage is:
Therefore, the power dissipated by each amplifier is:
Equation 2
and the maximum value is obtained when:
and its value is:
Equation 3
This maximum value is only dependent on the power supply voltage and load values.
The efficiency is the ratio between the output power and the power supply:
Equation 4
The maximum theoretical value is reached when V
The maximum die temperature allowable for the TS4994 is 125°C. However, in case of
overheating, a thermal shutdown set to 150°C, puts the TS4994 in standby until the
temperature of the die is reduced by about 5°C.
P
P
supply
P
diss
diss
I
Pdiss
CC
η =
P
=
AVG = 2
=
out
=
η =
max
2 2V
---------------------- P
P
------------------ - =
P
V
π R
∂P
---------------- - = 0
=
supply
P
supply
CC
∂P
π
---- - = 78.5%
=
4
out
V
-------------------- - (W)
diss
2
peak
out
⋅
CC
2R
L
π
Vcc
2
V
---------------- - (A)
I
R
–
CC
πR
L
peak
L
2
P
2
--------------------
πV
peak
AVG
4V
L
out
out
(
W
peak
)
CC
–
P
= V
out
(W)
(W)
CC
, so:
Application information
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