AD723ARU-REEL Analog Devices Inc, AD723ARU-REEL Datasheet
AD723ARU-REEL
Specifications of AD723ARU-REEL
Related parts for AD723ARU-REEL
AD723ARU-REEL Summary of contents
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PRODUCT DESCRIPTION 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 ...
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AD723–SPECIFICATIONS inputs terminated with 75 . Outputs configured in active termination mode, 75 Parameter SIGNAL INPUTS (RIN, GIN, BIN) Input Amplitude Clamp Level Input Resistance Input Capacitance TERMINATION SWITCH CHARACTERISTICS (RT, GT, BT) Input Capacitance Switch On Resistance LOGIC INPUTS ...
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... JA Thermal Resistance measured on SEMI standard 4-layer board. Model AD723ARU AD723ARU-REEL AD723-EVAL CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD723 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high-energy electrostatic discharges ...
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AD723 Pin Mnemonic Description 1 STND Encoding Standard Pin. A Logic HIGH signal is used for NTSC encoding, a Logic LOW signal signifies PAL When SA is high, phase alternation accompanies NTSC bandwidths and timing for support of ...
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FSC (3.579545MHz OR 4.433618MHz) OSCILLATOR 1.0 0.5 0.0 APL = 51.2% 525 LINE NTSC NO FILTERING SLOW CLAMP TO 0.0V @ 6.63 s –0 µs NOISE REDUCTION: 15.05dB APL = 50.7% SETUP 7.5% Typical Performance ...
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AD723 1.0 APL = 46.6% 525 LINE NTSC NO FILTERING SLOW CLAMP TO 0.00V @ 6.63 s 0.5 0.0 –0 200mV 1.0 APL = 34.8% 625 LINE PAL NO FILTERING SLOW CLAMP TO 0.00V ...
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APL = 48.2% 525 LINE NTSC NO FILTERING SLOW CLAMP TO 0.00V @ 6.63 s 0.5 0.0 –0 TIMING MEASUREMENT RS–170A (NTSC) FIELD = 1 LINE = 21 9.30 s 5.46 s ...
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AD723 THEORY OF OPERATION The AD723 is a predominantly analog design, with digital logic control of timing. This timing logic is driven by an external frequency reference at four times the color subcarrier frequency, input into the 4FSC pin of ...
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After the luma prefilter, the bandlimited luma signal is sampled onto a set of capacitors at twice the master reference clock rate. After an appropriate delay, the data is read from the delay line, reconstructing the luma signal. The 8FSC ...
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AD723 Current Mode Output Drivers In order to deliver a full swing video signal from a supply voltage as low as 2.7 V, the AD723 uses current mode output drivers. Bright colors like fully saturated yellow can reach peak ampli- ...
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Power-Down Load Checking One of the main uses of the TVDET signal is for plug-and-play operation. When this feature is used, a VGA controller or other IC polls the AD723 at regular intervals (such as once per second) to see ...
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AD723 HSYNC/VSYNC (USER INPUTS) RIN/GIN BIN (USER INPUTS) MODULATOR RESTORE INPUT CLAMPS BURST FLAG/ DELAY LINE RESET Y C Symbol Name Description t Sync Width Input valid sync width for burst SW insertion (user-controlled). t Sync to Blanking Minimum sync ...
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APPLYING THE AD723 Inputs RIN, BIN, GIN are analog inputs that should be terminated to ground with 75 Ω in close proximity to the IC. These connect directly to ground for direct input termination as in Figure 7. For switched ...
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AD723 Basic Connections Some simple applications will not require use of all of the fea- tures of the AD723. In such a case, some of the pins must be connected to appropriate levels such that the rest of the device ...
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V CC ESD PROTECTION RED GREEN BLUE GRAPHICS SUBSYSTEM HSYNC VSYNC DDCSCL 5V DDCSDL 5V 75 0.1 F GPO CE GPO TERM GPI I/O TVDET CONTROLLER GPO SA GPO STND OPTIONAL R1 1M U1A U1B HC04 HC04 R2 Y1 200 ...
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AD723 One well-known distortion of composite video images is called dot crawl. It shows moving dot pattern at the interface between two areas of different color caused by the inability of the monitor circuitry to ...
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Synchronous vs. Asynchronous Operation The source of RGB video and synchronization used as an input to the AD723 in some systems is derived from the same clock signal as used for the AD723 subcarrier input (4FSC). These systems are said ...
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AD723 Implementing a Luma Trap The AD723 implementation of a luma trap uses an on-chip resistor along with an off-chip inductor and capacitor to create an RLC notch filter. The filter must be tuned to the center frequency of the ...
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SYNCHRONIZING SIGNALS The AD723 requires explicit horizontal and vertical synchroniz- ing signals for proper operation. This information cannot and should not be incorporated in any of the RGB signals. However, the synchronizing information can be provided as either separate horizontal ...
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AD723 PIN 1 0.006 (0.15) 0.002 (0.05) SEATING PLANE OUTLINE DIMENSIONS Dimensions shown in inches and (mm). (mm) are the controlling dimension. 28-Lead TSSOP (RU-28) 0.386 (9.80) 0.378 (9.60 0.177 (4.50) 0.169 (4.30) 0.256 (6.50) 0.246 (6.25) 1 ...