AD723 2.7 V to 5.5 V RGB-to-NTSC/PAL Encoder with Load Detect and Input Termination Switch

The AD723 is a low cost RGB-to-NTSC/PAL encoder that converts analog red, green, and blue color component signals into their corresponding luminance and chrominance signals for display on an NTSC or PAL television. Luminance (Y) and Chrominance (C) signals are available individually for S-video, or combined for composite video (CV). All outputs are available separately and optimized for driving 75 Ω loads. Active termination is used for lower power consumption.

A smart load detect feature powers down unused outputs and can be used to monitor the continuing presence or absence of an external TV. This enables plug-and-play operation. In addition, a logic controlled triple switch at the input solves the applications problem of differing load conditions when an RGB monitor is disconnected. When an RGB monitor is not present, the R, G, and B terminations are enabled by the user. This solution ensures no loss of video bandwidth when the RGB monitor is in operation.

In PC applications, flicker filter support is provided by the graphics controller, which has direct access to memory. Underscan compensation, necessary for uses other than video or DVD, is supported through choice of RGB output clocks and sync intervals.

An optional luminance trap (YTRAP) provides a means of reducing cross color artifacts due to subcarrier frequency information in the Y signal.

The AD723 is available in a 28-lead TSSOP package and is capable of operation from supplies of 2.7 V to 5.5 V.

Features and Benefits
  • Low cost, fully integrated solution for NTSC/PAL
  • Composite and Y/C (S-video) outputs
  • Current output drives 75 Ω loads
    DC-coupled: supports tv load detect
    No large ac-coupling capacitors at output
    Self-power-down of unloaded output drivers
  • Triple switch to enable RGB termination
  • Integrated delay line and auto-tuned filters
  • Y-trap to eliminate cross color artifacts
  • 3 V supply operation: low power
    < 100 mW: composite active (typical)
    < 150 mW: S-video active (typical)
    <1 µA: power down current
  • Audio & Video Products
    Software & Systems Requirements
    Data Sheets
    Documentnote
    AD723: 2.7 V to 5.5 V RGB-to-NTSC/PAL Encoder with Load Detect and Input Termination Switch Data Sheet (Rev. 0)PDF 678 kB
    Application Notes
    Documentnote
    AN-205: Video Formats and Required Load TerminationsPDF 241 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    AD723ARUZ Production28 ld TSSOP (4.4mm)OTH 50-40 to 85C4.483.81Y
    AD723ARUZ-REEL Production28 ld TSSOP (4.4mm)REEL 2500-40 to 85C4.483.81Y
    AD723ARUZ-REEL7 Production28 ld TSSOP (4.4mm)REEL 1000-40 to 85C4.483.81Y
    AD723WARUZ-RL7 Production28 ld TSSOP (4.4mm)REEL 1000-40 to 85C4.483.81Y
    Evaluation Boards
    Part NumberDescriptionPriceRoHS
    AD723-EBZEvaluation Board266Y
    AD723: 2.7 V to 5.5 V RGB-to-NTSC/PAL Encoder with Load Detect and Input Termination Switch Data Sheet (Rev. 0) ad723
    AD72X 评估板软件 ad724
    AN-205: Video Formats and Required Load Terminations adv7202