General Description; Special Features - Harman Kardon FL8550 Service Manual

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General Description

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The PMD-100 HDCD Process Decoder is a sophisticated
0.6 micron CMOS Integrated Circuit that performs pre-
cise decoding of HDCD encoded recordings. The Decoder
also functions as a state-of-the-art digital filter when fed
data from non-HDCD recordings. It is designed to inter-
face directly with popular data receivers and DAC's, elimi-
nates the need for conventional monolithic digital filters.
The PMD-100 has been carefully designed to maximize per-
formance and ease of use in a wide variety of applications.
HDCD Process Information
Data encoded with HDCD process information carries pre-
cisely encrypted signals, hidden within the LSB of the 16-
bit data word. Over time, only 1 to 5% of the LSB is used
for this hidden code. The encoded information is inau-
dible and causes no perceptible loss of information. The
PMD-100 recognizes the encrypted signals as HDCD pro-
cess information, and directs the decoding function to pre-
cisely reconstruct the high resolution signal in a form ap-
propriate for output to the D-A converter being used.
Note: To preserve HDCD process information, no alteration
of the encoded data is allowed prior to processing by the PMD-
100. Digital data processing including phase inversion prior to
the PMD-100 input will result in the loss of HDCD process
information encoded in the data.
9300-0005
Rev A1

SPECIAL FEATURES

Automatic HDCD Process Decoding
When the PMD-100 detects HDCD
mation in the input data, it automatically switches to
HDCD
an LED indicator. When non-HDCD
data is received, the decoder automatically operates
as a high performance digital filter.
Excellent Filter Characteristics
When operating as a digital filter, the PMD-100 ex-
hibits passband characteristics that have been care-
fully optimized to provide extremely accurate sound
quality. Passband ripple from 0 to 20 kHz is within
±.0001 dB and stopband attenuation is greater than
120 dB.
Two Operating Modes
Stand-Alone
In Stand-Alone Mode, the PMD-100 requires no
external controller, allowing for the most cost
effective designs.
Program
In Program mode, an external processor controls
the PMD-100's many advanced operating modes
and features.
HDCD
HDCD® and High Definition Compatible Digital®
are registered trademarks of Pacific Microsonics, Inc
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PMD-100
PMD-100 Process Decoder
decode mode, and provides an output to drive
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FL8550
® process infor-
® process input