saa7327 NXP Semiconductors, saa7327 Datasheet - Page 22

• Manufacturer Part Number: saa7327
• Description: Digital Servo Processor And Compact Disc Decoder With Integrated Dac For Video Cd Cd7 Ii
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7.13
7.13.1
The spindle motor speed is controlled by a fully integrated
digital servo. Address information from the internal
calculate the motor control output signals. Several output
modes, selected by decoder register 6, are supported:
2000 Jun 26
8 frame FIFO and disc speed information are used to
Pulse density, 2-line (true complement output),
(1
PWM output, 2-line, (22.05
frequency
PWM output, 4-line, (22.05
frequency
CDV motor mode.
Digital servo processor and Compact Disc
decoder with integrated DAC for video CD (CD7 II)
n) MHz sample frequency
Spindle motor control
M
OTOR OUTPUT MODES
MOTO2
MOTO1
MOTO1
MOTO1
22 k
n) kHz modulation
n) kHz modulation
t
22 k
rep
10 nF
V DD
Fig.14 Motor pulse density application diagrams.
22 k
= 45 s
V SS
Accelerate
V SS
Fig.15 2-line PWM mode timing.
22 k
+
–
10 nF
V SS
22 k
22 k
+
–
22
M
7.13.1.1
In the pulse density mode the motor output pin (MOTO1)
is the pulse density modulated motor output signal. A 50%
duty factor corresponds with the motor not actuated,
higher duty factors mean acceleration, lower mean
braking. In this mode, the MOTO2 signal is the inverse of
the MOTO1 signal. Both signals change state only on the
edges of a (1
application diagrams are illustrated in Fig.14.
7.13.1.2
In the PWM mode the motor acceleration signal is put in
pulse-width modulation form on the MOTO1 output.
The motor braking signal is pulse-width modulated on the
MOTO2 output. The timing is illustrated in Fig.15. A typical
application diagram is illustrated in Fig.16.
t
dead
V DD
240 ns
M
+
–
Pulse density output mode
PWM output mode (2-line)
n) MHz internal clock signal. Possible
V SS
Brake
V
SS
10 nF
22 k
MGA363 - 1
MOTO2
MGA366
Product specification
SAA7327