TS4985

Application Information

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By following previous rules, the TS4985 can reach near zero pop and click even with high gains

such as 20dB.

Example calculation:

With

standard value which gives a lower cut-off frequency equal to 18.5Hz. In this case,

(

read 20ms max. This value is twice as high as our current value, thus we can state that pop and

click will be reduced to its lowest value. Minimizing both

phenomena, and the cost and size of the application.

4.9

Dedicated standby control

TS4985 has two standby control inputs to allow to put each channel in standby mode

independently. In case a channel is active and another one in standby mode It’s very important

to be in line with a following recommendation to reach near zero pop. When left (right) channel

is active and right (left) channel is in standby mode it's necessary to put active channel in

standby mode first and then immediately (with regard to Standby time) activate right (left)

channel or both channels together in at the same moment.

4.10

Application example: differential-input BTL power stereo

amplifier

The schematic in

Figure 65 shows how to design the TS4985 to work in differential-input mode.

For this discussion, only the left-channel amplifier will be referred to.

Let:

The gain of the amplifier is:

Figure 65.

12

34

0

40

80

120

160

Vcc=5V

Vcc=3.3V

Vcc=2.6V

Tamb=25

Bypass Capacitor Cb ( F)

Gvdif = 2

R2

R1

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