Application Information

TS4975

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The efficiency is the ratio between the output power and the power supply:

The maximum theoretical value is reached when Vpeak = Vcc/2, so

The TS4975 is stereo amplifier so it has two independent power amplifiers. Each amplifier

produces heat due to its power dissipation. Therefore the maximum die temperature is the sum

of each amplifier’s maximum power dissipation. It is calculated as follows:

●

●

●

Single ended configuration:

Phantom ground configuration:

4.3

Low frequency response

Input capacitor Cin

The input coupling capacitor blocks the DC part of the input signal at the amplifier input. In the

low-frequency region, Cin starts to have an effect. Cin with Zin forms a first-order, high-pass

filter with -3 dB cut-off frequency.

Zin is the input impedance of the corresponding input (30 k

Ω for In1 & In2).

Note:

For all inputs, the impedance value remains for all gain settings. This means that the lower cut-

off frequency doesn’t change with gain setting. Note also that 30 k

η

P

OUT

P

supply

-------------------

πV

PEAK

4V

CC

---------------------

==

η

π

8

---

39.25%

==

TotalP

diss

2P

diss1

=

TotalP

diss

π R

L

---------------------- P

OUT

2P

()

–

=

TotalP

diss

π R

L

---------------------- P

OUT

2P

()

–

=

F

CL

1

2

πZ

------------------------Hz

()

=