Application information

TS4657

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Figure 50. Audio interface formats managed by the TS4657

4.2

Power-management unit

The TS4657 utilizes a power-management unit to supply its internal structures.

A self-generated negative supply enables the drivers to be powered from positive and

negative supplies, therefore increasing the amplitude of the output signal. This internal

negative supply switches at a higher frequency than traditional architectures, derived from

the master clock MCLK. This structure uses an original design that enables one to suppress

the flying or floating capacitors. Therefore, only four small ceramic X5R 10V 1-µF

decoupling capacitors are necessary for VCCA/VCCD and VREGA/VREGD.

Furthermore, the self-generated negative supply allows the amplifier outputs to be centered

around zero, thus the bulky output coupling capacitors can be removed.

LRCLK

SDAT

BCLK

LEFT

RIGHT

0

1

15

14

MSB

LSB

16

1

14

MSB

LSB

16-bit word right data

015

16-bit Right justified data format: pin FORMAT1 = VIL, FORMAT2 = VIL

LRCLK

SDAT

BCLK

LEFT

RIGHT

0

1

n-1

n-2

MSB

LSB

n-bit word left data

1

n-2

MSB

LSB

n-bit word right data

0n-1

Up to 24-bit left-justified data format: pin FORMAT1 = VIL, FORMAT2 = VIH

-bit word left data

LRCLK

SDAT

BCLK

LEFT

RIGHT

0

1

n-1

n-2

MSB

LSB

32-bit word left data

1

n-2

MSB

LSB

32-bit word right data

0

n-1

Up to 24-bit I²S data format: pin FORMAT1 = VIH, FORMAT2 = VIH

LRCLK

SDAT

BCLK

LEFT

RIGHT

0

1

n-1

n-2

MSB

LSB

n-bit word left data

1

n-2

MSB

LSB

n-bit word right data

0n-1

24-bit right-justified data format: pin FORMAT1 = VIH, FORMAT2 = VIL