Philips SD-5.31SL, Руководство по обслуживанию

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Circuit Descriptions, List of Abbreviations, and IC Data Sheets
EN 52 SD-5.31SL 9.
Interrupts
Table 9-3 Interrupt overview
SCART
Previously, an on-board circuit switches the 0_6_12V signal to
be 0V, 6V or 12V. This circuit is removed. Instead, the SCART0
and SCART1 signals are now directly available at the module
interface (pins 3 and 4 of connector 1800).
Miscellaneous
I2C
The SD5.31 module has two I2C buses. The slave I2C is using
hardware I2C (because of its speed) and the master uses
software I2C via GPIO ports.
The master I2C bus controls all on-board devices e.g. NVRAM,
audio DAC etc., while the slave I2C bus is used to connect to
an external processor e.g. a TV or Audio set microprocessor,
which acts as the I2C master controller.
An additional signal (I2C_INT) can be used to flag to the
external processor when data is available in the slave mode.
I2S
Two external I2S inputs can be connected to Ziva-5. However,
only one input can be used at any one time as they are
multiplexed inside the chip. On SD5.31, one input is coming
from an SPDIF-I2S converter (e.g. external source on an audio
set), while the other is from an external source (e.g. a TV
receiver audio section). The slash version of the module will
decide which input is used. Only 2-channel PCM I2S up to 96
kHz is currently supported.
Service Port Buffer
Figure 9-7 Service Port Buffer
The service port (see diagram M7) is simplified to reduce cost.
The unused RTS and CTS lines are no longer connected. A
transistor buffer (item 7702) is used instead of the Schmitt
Trigger buffer.
9.3.4
Motor drivers
Figure 9-8 Block diagram motor drivers
The following motor driver ICs are controlled by the Ali M5705:
•
The spindle motor driver.
•
The servo motor driver.
Both ICs require a reference voltage (MVREF2) of 2.1 V. This
voltage is generated with IC 7002 (pin 26 provides a reference
bias voltage of 2.5 V) and buffered with OpAmp 7003-A.
Spindle Motor Driver
The spindle motor interface provides both motor control signals
from the demodulator and, in addition, contains a tachometer
loop that accepts tachometer pulses from the (hall) motor unit.
They drive the motor IC (BA6849FP, item 7101).
BA6849FP Features:
–
Three-phase, full wave, pseudo-linear drive system.
–
Built-in power save and thermal shutdown functions.
–
Built-in current limiter and Hall bias circuits.
–
Built-in rotation direction detector.
–
Built-in reverse rotation prevention circuits.
Servo Motor Driver
The BA5954FP (item 7100) is a 4-channel motor driver with
built-in current feedback. Sensing is done via resistors 3110//
3112 for focus signals (pin 7) and resistors 3114//3115 for the
tracking signals (pin 20).
This driver controls the following motors:
•
Sledge motor (SL+ and SL-).
•
Loader motor (LD+ and LD-).
•
Focus motor (FO+ and FO-).
•
Tracking motor (TR+ and TR-).
BA5954FP Features:
–
Wide dynamic range.
–
Level shift circuit built-in.
–
Thermal shutdown circuit built in (at 175 deg. C.).
–
Stand-by mode built-in.
HIRQ nr. Device Ziva-5 Pin nr.
0 E-Link daughter card 24
1 ATAPI 184
2 N/u 116
100R
4K7
4K7
TDX_SER
1K
+5V
1n5
Out
10K
10K
10K
RXD_SER
10K
3V3
6K8
In
CL 36532043_011.eps
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+
_
+
_
+
_
+
_
Diff
Diff
X2
X2
Focus+
Radial-
6.7 ohm
100uH
6.7 ohm
100uH
Focus-
3K3 33K 10K 10K
7K5
X0.9
7K5
470p
3K3 33K 10K 10K
7K5
7K5
X0.9
MVREF2 (2V1)
MVREF2 (2V1)
+5 V
+5 V
14
13
0.5
21 27
1
2
3
7
27 21
15
16
0.5
26
12
11
24
25
20
470p
100p
100p
FOCUS
ALi
RADIAL
A
A
CL 36532043_017.eps
210503