0

5

10

15

20

25

30

35

40

6

8

10

12

14

16

18

20

G028

THD = 10%

THD = 1%

Gain = 20 dB

+ 33 µH

TPA3110D2

SLOS528E – JULY 2009 – REVISED NOVEMBER 2015

www.ti.com

10.2.5 Application Curve

Note: Dashed Lines represent thermally limited regions.

Figure 46. Output Power vs Supply Voltage (PBTL)

11 Power Supply Recommendations

The TPA3110D2 is designed to operate form an input voltage supply range between 8-V and 26-V. Therefore,

the output voltage range of power supply should be within this range and well regulated. The current capability of

upper power should not exceed the maximum current limit of the power switch.

The TPA3110D2 is a high-performance CMOS audio amplifier that requires adequate power supply decoupling

to ensure that the output total harmonic distortion (THD) is as low as possible. Power supply decoupling also

prevents oscillations for long lead lengths between the amplifier and the speaker. Optimum decoupling is

achieved by using a network of capacitors of different types that target specific types of noise on the power

supply leads. For higher frequency transients due to parasitic circuit elements such as bond wire and copper

trace inductances as well as lead frame capacitance, a good quality low equivalent-series-resistance (ESR)

ceramic capacitor of value between 220 pF and 1000 pF works well. This capacitor should be placed as close to

the device PVCC pins and system ground (either PGND pins or PowerPAD™) as possible.

For mid-frequency noise due to filter resonances or PWM switching transients as well as digital hash on the line,

another good quality capacitor typically 0.1

μF to 1 µF placed as close as possible to the device PVCC leads

works best. For filtering lower frequency noise signals, a larger aluminum electrolytic capacitor of 220

μF or

greater placed near the audio power amplifier is recommended.

The 220-

μF capacitor also serves as a local storage capacitor for supplying current during large signal transients

on the amplifier outputs. The PVCC terminals provide the power to the output transistors, so a 220 µF or larger

capacitor should be placed on each PVCC terminal. A 10-µF capacitor on the AVCC terminal is adequate. Also,

a small decoupling resistor between AVCC and PVCC can be used to keep high frequency class D noise from

entering the linear input amplifiers.

12 Layout

12.1 Layout Guidelines

The TPA3110D2 can be used with a small, inexpensive ferrite bead output filter for most applications. However,

since the Class-D switching edges are fast, it is necessary to take care when planning the layout of the printed

circuit board. The following suggestions will help to meet EMC requirements.

•

Decoupling capacitors—The high-frequency decoupling capacitors should be placed as close to the PVCC

and AVCC terminals as possible. Large (220 µF or greater) bulk power supply decoupling capacitors should

be placed near the TPA3110D2 on the PVCCL and PVCCR supplies. Local, high-frequency bypass

capacitors should be placed as close to the PVCC pins as possible. These caps can be connected to the

thermal pad directly for an excellent ground connection. Consider adding a small, good quality low ESR

24

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