SAA7371GP Philips Semiconductors, SAA7371GP Datasheet - Page 9

• Manufacturer Part Number: SAA7371GP
• Description: Digital servo processor and Compact Disc decoder CD7
• Manufacturer: Philips Semiconductors

Philips Semiconductors
2. Data capture performance is not optimized for these
7.2
The crystal oscillator is a conventional 2 pin design
operating between 8 MHz and 35 MHz. This oscillator is
capable of operating with ceramic resonators and with
both fundamental and third overtone crystals. External
components should be used to suppress the fundamental
output of the third overtone crystals as shown in Figs 3
and 4. Typical oscillation frequencies required are 8.4672,
16.9344 or 33.8688 MHz depending on the internal clock
settings used and whether or not the clock multiplier is
enabled.
1998 Jul 06
Digital servo processor and
Compact Disc decoder (CD7)
options.
Fig.3 8.4672 MHz fundamental configuration.
Crystal oscillator
Fig.4 33.8688 MHz overtone configuration.
MGR309
CROUT
MGR
CROUT
SAA7371
SAA7371
308
330
330
OSCILLATOR
OSCILLATOR
10 pF
22 pF
33.8688 MHz
8.4672 MHz
100 k
100 k
10 pF
22 pF
CRIN
CRIN
3.3 H
1 nF
9
7.3
The SAA7371 has an integrated slice level comparator
which can be clocked by the crystal frequency clock, or
8 times the crystal frequency clock (if SELPLL is set HIGH
while using an 8.4672 MHz crystal, and register 4 is set
to 0xxx). The slice level is controlled by an internal current
source applied to an external capacitor under the control
of the Digital Phase-Locked Loop (DPLL).
Regeneration of the bit clock is achieved with an internal
fully digital PLL. No external components are required and
the bit clock is not output. The PLL has two registers
(8 and 9) for selecting bandwidth and equalization.
For certain applications an off-track input is necessary.
This is internally connected from the servo part (its polarity
can be changed by the foc_parm1 parameter), but may be
input via the V1 pin if selected by register C. If this flag is
HIGH, the SAA7371 will assume that its servo part is
following on the wrong track, and will flag all incoming HF
data as incorrect.
Data slicer and clock regenerator
Product specification
SAA7371