TS4994

Application information

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4.10

Shutdown time

When the standby command is set, the time required to put the two output stages in high

impedance and the internal circuitry in shutdown mode is a few microseconds.

Note:

In shutdown mode, the Bypass pin and Vin+, Vin- pins are short-circuited to ground by

internal switches. This allows a quick discharge of the Cb and Cin capacitors.

4.11

Pop performance

Due to its fully differential structure, the pop performance of the TS4994 is close to perfect.

However, due to mismatching between internal resistors Rin, Rfeed, and external input

capacitors Cin, some noise might remain at startup. To eliminate the effect of mismatched

components, the TS4994 includes pop reduction circuitry. With this circuitry, the TS4994 is

close to zero pop for all possible common applications.

In addition, when the TS4994 is in standby mode, due to the high impedance output stage in

this configuration, no pop is heard.

4.12

Single-ended input configuration

It is possible to use the TS4994 in a single-ended input configuration. However, input

coupling capacitors are needed in this configuration. The schematic in Figure 79 shows this

configuration using the MiniSO-8 version of the TS4994 as an example.

Figure 79.

Single-ended input typical application

Rfeed1

20k

Rin1

20k

Rin2

20k

Rfeed2

20k

Cin1

220nF

Cin2

220nF

Cb

1u

Cs

1u

GND

GND

GND

Ve

GND

GND VCC

VCC

Optional

8 Ohms

Bias

Vin-

Vin+

Bypass

Standby

VCC

GND

Vo-

Vo+

+

-

2

4

7

8

6

3

5

1

Stdby

TS4994IS