Diodes PAM8603M - Manual (Page 11)

PAM8603M
Document number: DSxxxxx Rev. 1 - 1
11 of 14
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November 2012
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PAM8603M
A Product Line of
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Application Information
(cont.)
PCB Layout Guidelines Grounding
At this stage it is paramount to notice the necessity of separate grounds. Noise currents in the output power stage need to be returned to output
noise ground and nowhere else. Were these currents to circulate elsewhere, they may get into the power supply, the signal ground, etc, even
worse, they may form a loop and radiate noise. Any of these cases results in degraded amplifier performance. The logical returns for the output
noise currents associated with Class-D switching are the respective PGND pins for each channel. The switch state diagram illustrates that
PGND is instrumental in nearly every switch state. This is the perfect point to which the output noise ground trace should return. Also note that
output noise ground is channel specific. A two channel amplifier has two seperate channels and consequently must have two seperate output
noise ground traces. The layout of the PAM8603M offers separate PGND connections for each channel and in some cases each side of the
bridge. Output noise grounds must be tied to system ground at the power exclusively. Signal currents for the inputs, reference, etc need to be
returned to quite ground. This ground is only tied to the signal components and the GND pin, and GND then tied to system ground.
Ordering Information
Part Number Part Marking Package Type Standard Package
PAM8603MNHR
PAM8603M
XXXYWWLL
SSOP-24 2500 Units/Tape&Reel
PAM8603MDER
PAM8603M
XXXYWWLL
SOP-18 1000 Units/Tape&Reel
PAM8603MDET
PAM8603M
XXXYWWLL
SOP18 40 Units/Tube
Marking Information