MITSUI MTV-DV05, Руководство по обслуживанию

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SERVICE MANUAL
MT1336E
RF amplifier
1.General Description
MT1336 is a high performance CMOS analog front-end IC for both CD_ROM driver up to 48XS and
DVD_ROM driver up to 16XS. It also supports DVD_RAM lead up to 4XS Version 2. It contains servo
amplifiers to generate focusing error, 3-beam tracking error, 1 beam radial push-pull signal, RF level and
SBAD for servo functions. It also includes DPD tracking error signal for DVD_ROM application. For
DVD_RAM disks, there are also Differential Push-Pull (DPP) method for generating tracking signal and
Differential Astigmatic Detection (DAD) for processing focusing signal. Programmable equalizer and AGC
circuits are also incorporated in this chip to optimize read channel performance. In addition, this chip has
dual automatic laser power control circuits for DVD-ROM (DVD-RAM) and CD-ROM separately and
reference voltage generators to reduce external components. Programmable functions are implemented by
the access of internal register through bi-directional serial port to configure modes selection.
2. Features
·
RF equalizer with programmable fc from 3MHz to 70MHz and programmable boost from 3dB to 13dB.
·
MT1336 supports at least eight different kinds of pick-up heads with versatile input configuration for both
RF input stages and servo signal blocks.
·
3 beams tracking error signal generator for CD_ROM application.
· One beam differential phase tracking error (DPD) generator for DVD_ROM application.
· Differential push pull tracking error (DPP) generator for DVD_RAM application.
·
Focusing error signal generator for CD-ROM, DVD-ROM and DVD-RAM (DAD method).
·
RF level signal generator.
·
Sub-beam added signal for 3 beams CD-ROM.
·
One beam push-pull signal generator for central servo application.
· High speed RF envelop detection circuit with bandwidth up to 400KHz for CD-ROM.
· Defect and Blank detection circuits.
·
Dual automatic laser power control circuits with programmable level of LD monitor voltage.
·
Vref=1.4V voltage and V2ref=2.8V voltage generators.
·
V20=2.0V voltage for pick-up head reference.
·
Bi-directional serial port to access internal registers.
· 128-pin LQFP.
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