Philips EM6E Service Manual page 129

EN 168 9. EM6E AB
Table 9-2 DVD I/O expander signals
Signal Name I/O Description
EJECT I
+5V_DVD_OK I
IRQ O Interrupt line to OTC
DVD_MUTE I
DVD_IRQ I
12V_DVD_OK I
3V3_DVD_OK I
REAL_STANDBY O High to disable 12V, 5V and 3.3V
The output of audio sound is controlled by means of an
analogue switch HEF4053. The +12V_ENABLE signal must be
"low" to enable the sound from DVD.
9.10.5 Voltage Regulator
This part takes care for the voltages that are needed for the
(optional) DVD slot loader (+3.3V, +5V, and +12V)
The L4978 is a step-down switching regulator delivering a 3.3
V. The device uses an internal power D-MOS transistor (with a
typical Rds_on of 0.25 W) to obtain high efficiency and high
switching speed. A switching frequency of 150 kHz is set via
C2406 and R3400. Input voltage is derived from the +11V
coming from the Standby supply.
Other features of this DC-DC converter include pulse-by-pulse
current limit, hiccup mode for short circuit protection, voltage
feed forward regulation, soft-start, protection against feedback
loop disconnection, inhibit for zero current consumption and
thermal shutdown.
Notes:
•
The LEDs on this board are not stuffed in production, they
only were used during development for debugging
purposes.
•
Switch 1300, is also only meant for development purposes.
9.10.6 Interface Board Signal Descriptions
Table 9-3 Interface board signal descriptions
Signal Description
11V_STANDBY Stand by supply voltage
5V Supply voltage
SPDIF_DVD SPDIF from e.g. an internal DVD drive
12V_AUDIO Supply voltage for the radio module
ECO6
DVD_L/R Audio from DVD module
RADIO_L/R Audio from radio module
OUT_L/R Audio output of the module
+12V_ENABLE Control signal to switch on the radio
module
DATA/CLOCK/ Control signals for the radio module
MONO/STEREO
WRITE_ENABLE Control signal for the radio
MPX Multiplex signal containing audio and
RDS information
DAVN Data available signal from the RDS de-
coder chip
I2C_S Software I2C bus
USW1_LCD_DO Indicates the close-end position of the
WN LCD display
Circuit Descriptions, Abbreviation List, and IC Data Sheets
Low when the DVD Eject knob is
pressed (not used for TDL)
Low when the 5V supply to DVD is
off
Mute indication from DVD
Interrupt line from DVD
Low when the 3.3V supply to DVD
is off
Low when the 3.3V supply to DVD
is off
supply to DVD
Signal Description
USW2_LCD_UP Indicates the open-end position of the
LCD display
FORWARD Control line for the motor control
L9997ND
REVERSE Control line for the motor control
L9997ND
ENABLE Control line for the motor control
L9997ND
M+ Positive motor voltage
M- Negative motor voltage
I2C I2C bus to host
IRQ Interrupt request line to host
9.11 Software Upgrading
9.11.1 Introduction
In this chassis, you can upgrade the software via ComPair.
This offers the possibility, to replace the entire SW image
without having to remove the flash-RAM from its socket. You
can find more information on how this procedure works in the
ComPair file. It is possible that not all sets are equipped with
the hardware, needed to make software upgrading possible. To
speed up the programming process, the firmware of the
ComPair interface can be upgraded. See Chapter "Service
Modes ..."; paragraph "ComPair" - "How To Order" for the order
number.
9.11.2 Specifications
Some specifications are:
•
The upgrade feature makes use of I2C to transfer a new
SW image (4 MB).
•
It requires the ComPair interface Box (RS232 to I2C).
•
The I2C bus is available at the rear side of the set, BUT it
is still necessary to open the set to place a dedicated
jumper. This, to avoid FCR (Field Call Rates).
•
It uses a ZIP-compressed BIN image to speed up the
transfer process (1/2 size).
•
The complete procedure takes less than 20 minutes with
an upgraded ComPair interface:
–
About 90 seconds to erase a 4 MB flash-RAM.
–
Less than 10 minutes to transfer the file (max 1.9 MB).
–
About 5 minutes to decompress/program the flash-
RAM
Note: It takes about 85 minutes with a standard interface.
Constraints:
•
Needs the EPG flash memory, so this device must be
placed also for non-EPG regions like Asian Pacific and
United States.
Advantages:
•
Flexibility.
•
No change in internal ROM (IROM) required (IROM not
used).
•
Flexibility to change of code flash manufacturer as the
"flash driver" is part of the bootstrap code (part of the main
software image).