Daewoo DDT-21H9ZDF(21"), Руководство по обслуживанию

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CIRCUIT OPERATIONAL DESCRIPTION
2) Flash Memory : MX29LV800ATTC-70 or A29L800TV-70 (IC03)
This stores every program required for the operation of DVD player and holds the data of OSD
languages and LOGO and send them upon request from u-COM.
This allows the update of firmware by CD-R/RW. For DVD module, 8MBit Flash Memory on 512K x
16bit basis is used.
3) LATCH : SN74HC573APWR or MM74HC573NTC (IC06, IC07)
74HC573 is 3-State Octal D-Type Latch and generally used for temporarily maintaining or storing the
signal status, but two latches applied to DVD module plays the role of sharing low 16bit of data and
address bus for the data transfer between MPEG decoder and flash memory. This method has been
adopted due to the lack of the M3351 Flash memory port.
4) SDRAM : EM638325TS-6 or MT48LC2M32B2TG-6 (IC04)
This sends and receives data with MPEG decoder and performs the video signal processing. Every
video signal output from DVD player is once stored in SDRAM and then encoded in MPEG decoder
and finally output into the analog signal.
SDRAM applied to DVD module has the capacity of 64MBit(512K x 32bit x 4Bank),sends and
receives data with MPEG decoder by 32 bit. SDRAM system clock is 81MHz, three times of 27MHz of
X-TAL.
5) RESET IC : BD5229G-TR (IC02)
This is a hardward reset circuit which is automatically reset after powering DVD module. In reset
status, it reads the firmware information from flash memory and move it to the data field of SDRAM
and then the system is initialized. As for BD5229G-TR, it gets the status of High after 200ms reset
active time from the moment of power on.
6) EEPROM : 24WC08J or AT24C08N (IC05)
This stores the information related to setup of DVD menus. This can read and write the optional
information such as OSD, voice, language option after function for subtitle etc, the aspect or method
of TV display, video option like display function and audio, screen saver, parental function through the
I
2 C transmission method.
7) OP-AMP : TL3472CDR (IA03)
TL3472CDR is OP-AMP which generates the MIRROR signal of the monitoring signal required for
the Servo control stablization or performs the spindle break function using the electromotive force
generated during motor backlashing. In this case, the MIRROR signal is generated in the RF IC and
used for the spindle break only.
8) MUTE Diode : DAN202K (DB01)
DAN202K consists of two diodes and processes optionally the MUTE of the audio signal through
audio DAC(IB01, IB02) and the function through MUTE command from u-COM.