Diodes PAM8615 - Manual (Page 9)

PAM8615
Document number: DSxxxxx Rev. 1 - 1
9 of 14
www.diodes.com
October 2012
© Diodes Incorporated
PAM8615
A Product Line of
Diodes Incorporated
Test Setup for Performance Testing
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.
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 35µm 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.
Volume Control
A DC volume control section is integrated in PAM8615, controll ing via DCV and DGND terminals. The voltage on DCV pin, determines internal
amplifier gain as listed in Page 6.
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 Page 6.
MUTE Operation
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.