SAA7806H NXP [NXP Semiconductors], SAA7806H Datasheet - Page 46

• Manufacturer Part Number: SAA7806H
• Description: One chip automotive CD audio device
• Manufacturer: NXP [NXP Semiconductors]

Philips Semiconductors
9397 750 13697
Objective data sheet
6.6.8.5 Writing and reading motor integrator value
6.6.8.6 Some notes on application motor servo
6.7.1 PDSIC Registers and servo RAM control
6.7 Digital Servo - PDSIC
It is possible to obtain the integrator value by reading the registers MotorIntLSB and
MotorIntMSB. The integrator can be written at the same location. By opening all switches,
the user can bypass the whole control and filter part, and just use the block as a DAC for
the motor drivers. The control part can then be done in software.
The motor servo can be used to control the motor during CLV playback and also during
CAV or pseudo-CLV lock-to-disc or jump mode.
The digital servo block on SAA7806 is an evolution of the design used for the SAA7824
IC, and is referred to as Parallel Digital Servo IC (PDSIC). The ‘parallel’ description refers
to the microcontroller interface to the servo block - this is now a high speed parallel
interface, whereas it was previously a serial interface (e.g. a SAA7824 3/4 wire, I
The other features of the PDSIC are:
The servo block is controlled by two parts of the design - the servo control registers which
are used to control the writing of commands and parameters to the servo; and the servo
RAM. The servo RAM has two roles: storage of the servo parameters and capture of
commands and parameters during the command process.
All of the servo write commands consist of a command byte followed by a number of
parameter bytes (between 1 and 7), all of which have to be loaded into the PDSIC using a
serial communication interface.
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In CLV mode, both SW1 and SW2 must be closed
In CAV / pseudo-CLV mode, SW2 must be open and SW1 may be open
The motor servo will revolve the disc at the speed corresponding to the frequency set
point; in CLV mode with lock to EFM, the frequency set point must be set equal to the
desired readout frequency of the HF-PLL
Accelerating the disc must be done in one of the start modes
Braking the disc must be done in one of the stop modes.
Programmable ADC for CD-RW playback compatibility
Diode signal processing
Signal conditioning
Focus and radial control system
Access control
Sledge control
Shock detector
Defect detector
Off-track counting and detection
Automatic closed-loop gain control available for focus and radial loops
High-level features.
Rev. 01 — 20 June 2005
One chip automotive CD audio device
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
SAA7806
2
C-bus).
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