AT78C1503 datasheet pdf

1 Features •Operating Supply Range 3.0V to 3.6V •Power Dissipation 1W Max •Low-power Sleep Mode (<0.5 mW) •RF Data Channel – Automatic Gain Control or Programmable Gain Mode – Wide Bandwidth VGA – VGA Accepts Inputs from 30–300 mV Peak-to-peak Differential (PPD), 60–600 mV PPD or 110–1100 mV PPD – Programmable Equalization via 7th-order Equiripple Filter with Programmable Symmetric Zeros – Programmable 5-to-1 Filter Cutoff Range – Data Slicer with DC Restore Circuit – Wide Frequency Range Clock Extraction – Frequency Synthesizer with Independent 7-bit M and 6-bit N Dividers, Better than 1% Resolution – Highly Programmable to Accommodate DVD (1–5X) and CD (6–30X) – Write Asymmetry Measurement for Adjusting Write-mode Power – Data Recovery Supports CLV, ZCLV, ZCAV Recording – Optional Internally-generated Timing for AGC and Timing Recovery •Synthesizer Functions – Supports Wobble Clock Synthesis, Using Low-jitter PLL •Servo Algebra and OPC Functions – 45 MHz Bandwidth for Differential Phase Tracking Detector – Land and Groove Detector for DVD RAM – Supports One Beam Push/Pull Tracking Output – Supports One Beam Differential Phase Tracking – Supports Three-beam Push/Pull Tracking Output, Using E, F, G, H – Focus Error Signal Output – Focus OK Signal – Track Crossing Detection – Mirror Signal Output – Wobble Detection for DVD RAM, DVD-RW, DVD-R – Detects Tracking Error OK – Provides Sample and Hold Functions for CD and DVD OPC – Formats Pre-pit Data, Using Raw Pre-pit Information from AT78C1503 •Header Detection for DVD RAM Description The AT78C1503 is a programmable DVD/CD channel responsible for servo algebra, gain con- trol, equalization, bit detection and clock extraction for CD-ROM, DVD-ROM, DVD-R, DVD-RW and DVD-RAM formats. Programmable features allow data rates up to 5X DVD. Also, for DVD- RAM functionality, the channel serves the write path providing laser power control and pit asym- metry detection. Up to 2X DVD write speeds are supported for DVD-R, DVD-RW and DVD- RAM. The extracted wobble frequency is supplied to the AT78C1507 companion chip which in turn synthesizes the write clock. The AT78C1507 is the companion chip to the AT78C1503 – DVD/CD Read Channel – and the AT78C1504 – DVD/CD Automatic Laser Power Controller. Working in conjunction with the read channel, the AT78C1507 is responsible for wobble clock synthesis for DVD-R and DVD-RAM formats. In addition, the two parts working together also support pre-pit data and clock recovery for the DVD-R format. Four separate inputs are provided to enable the AT78C1507 to perform tracking servo algebra, using just the outrigger photo detector signals (E, F, G, H for example) coming from the OPU. This extends the range of supported tracking servo algebra functions for the 1503-1507 combination. Lastly, OPC capability is supported for efficient writing of DVD-R, DVD-RAM and CD-R disks. Based on CMOS technology, both the AT78C1503 and AT78C1507 operate from a single 3.3V supply and are fully programmable through serial interfaces for both CD and DVD modes. DVD/CD Read Channel AT78C1503 AT78C1507 Rev. 2054A–DVD–07/02

Features

• •Operating Supply Range 3.0V to 3.6V
• •Power Dissipation 1W Max
• •Low-power Sleep Mode (<0.5 mW)
• •RF Data Channel
• •Synthesizer Functions
• •Servo Algebra and OPC Functions
• •Header Detection for DVD RAM