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APPLICATION INFORMATION

PCB Material Recommendation

PVDD Capacitor Recommendation

Decoupling Capacitor Recommendations

System Design Recommendations

GVDD(+12V)

VDD(+12V)

PVDD

PVDD

GVDD(+12V)

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

GND

TAS5508/18

PWM1_P

PWM1_M

PWM2_P

PWM2_M

VALID

Microcontroller

I2C

10µH

100nF

50V

10µH

100nF

TAS5342LDDV

GVDD_B

OTW

SD

PWM_A

RESET_AB

PWM_B

OC_ADJ

GND

AGND

VREG

M3

M2

M1

PWM_C

RESET_CD

PWM_D

GVDD_C

GVDD_D

BST_D

PVDD_D

OUT_D

GND_D

GND_C

OUT_C

PVDD_C

BST_C

BST_B

PVDD_B

OUT_B

GND_B

GND_A

VDD

GVDD_A

BST_A

PVDD_A

OUT_A

NC

NC

NC

NC

NC

PVDD_D

PVDD_A

NC

25V

33nF

100nF

50V

100nF

50V

100nF

470nF

100nF

50V

10µH

470µF

50V

470 F

µ

50V

33nF 25V

3.3 W

100nF

0 W

27k

100nF

33nF 25V

100nF

50V

10nF

50V

100nF

470nF

100nF

100nF

50V

33nF

25V

100nF

50V

100nF

10µH

3.3 W

10nF

50V

10nF

50V

3.3 W

1nF

50V

1nF

50V

1nF

50V

1nF

50V

3.3 W

10nF

50V

10nF

50V

3.3 W

3.3 W

10nF

50V

10 W

10 W

10 W

10 W

50V

GND

2

1

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

23

22

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

TAS5342L

SLAS558 – OCTOBER 2007

FR-4 Glass Epoxy material with 2 oz. (70

μm) is recommended for use with the TAS5342L. The use of this

material can provide for higher power output, improved thermal performance, and better EMI margin (due to

lower PCB trace inductance.

The large capacitors used in conjunction with each full-birdge, are referred to as the PVDD Capacitors. These

capacitors should be selected for proper voltage margin and adequate capacitance to support the power

requirements. In practice, with a well designed system power supply, 1000

μF, 50-V will support more

applications. The PVDD capacitors should be low ESR type because they are used in a circuit associtated with

high-speed switching.

In order to design an amplifier that has robust performance, passes regulatory requirements, and exhibits good

audio performance, good quality decoupling capacitors should be used. In practice, X7R should be used in this

application.

The voltage of the decoupling capactors should be selected in accordance with good design practices.

Temperature, ripple current, and voltage overshoot must be considered. This fact is particularly true in the

selection of the 0.1

μF that is placed on the power supply to each half-bridge. It must withstand the voltage

overshoot of the PWM switching, the heat generated by the amplifier during high power output, and the ripple

current created by high power power output. A minimum voltage rating of 50-V is required for use with a 32.0 V

power supply.

The following schematics and PCB layouts illustrate "best practices" in the use of the TAS5342L.

Figure 14. Typical Differential (2N) BTL Application With AD Modulation Filters

16

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