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Power Analog Microelectronics Inc

www.poweranalog.com

Application Information

Power and Heat Dissipation

Choose speakers that are able to stand large

output power from the PAM8615. Otherwise,

speaker may suffer damage.

Heat dissipation is very important when the

device works in full power operation. Two factors

affect the heat dissipation, the efficiency of the

device that determines the dissipation power, and

the thermal resistance of the package that

determines the heat dissipation capability.

Generally, class-D amplifiers are high efficiency

and need no heat sink. For high power ones that

has high dissipation power, the heat sink may also

not necessary if the PCB is carefully designed to

achieve good heat dissipation by the PCB itself.

Dual-Side PCB

To achieve good heat dissipation, the PCB's

copper plate should be thicker than 35um and the

copper plate on both sides of the PCB should be

utilized for heat sink.

The thermal pad on the bottom of the device

should be soldered to the plate of the PCB, and

via holes, usually 9 to 16, should be drilled in the

PCB area under the device and deposited copper

on the vias should be thick enough so that the

heat can be dissipated to the other side of the

plate. There should be no insulation mask on the

other side of the copper plate. It is better to drill

more vias on the PCB around the device if

possible.

A DC volume control section is integrated in

PA M 8 6 1 5 , c o n t ro ll i n g v ia D C V a n d D G N D

terminals. The voltage on DCV pin, determines

internal amplifier gain as listed in Page6.

If a resistor divider is used to fix gain of the

amplifier, the DCV terminal can be directly

connected to the resistor divider connected

across AVDD and DGND. For fixed gain, the

resistor divider values are calculated to center

the voltage given in Page6.

The MUTE pin is an input for controlling the

output state of the PAM8615. A logic high on this

pin disables the outputs and low enables the

outputs. This pin may be used as a quick disable

or enable of the outputs without a volume fade.

Volume Control

MUTE Operation

Notes

1. The AP AUX-0025 low pass filter is necessary for class-D amplifier measurement with AP analyzer.

2. Two 22µH inductors are used in series with load resistor to emulate the small speaker for effic iency

measurement.

Test Setup for Performance Testing

AP System One

Generator

PAM8615 Demo Board

+OUT

Input

Load

AP

Low Pass

Filter

AUX-0025

AP System Two

Analyzer

GND

-OUT

VDD

Power Supply

PAM8615

16W/32W Stereo Class-D Audio Power Amplifier

02/2012 Rev1.1