SAA7374GP PHILIPS [NXP Semiconductors], SAA7374GP Datasheet - Page 9

• Manufacturer Part Number: SAA7374GP
• Description: Low voltage digital servo processor and Compact Disc decoder CD7LV
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
7.2
The crystal oscillator is a conventional 2 pin design
operating between 8 and 35 MHz. This oscillator is
capable of operating with ceramic resonators as well as
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 Feb 26
Low voltage digital servo processor and
Compact Disc decoder (CD7LV)
Fig.3 8.4672 MHz fundamental configuration.
Crystal oscillator
Fig.4 33.8688 MHz overtone configuration.
MBG658
CROUT
MBG650
CROUT
SAA7374
SAA7374
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 SAA7374 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 SAA7374 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
SAA7374