AD9985A/PCB Analog Devices Inc, AD9985A/PCB Datasheet
AD9985A/PCB
Specifications of AD9985A/PCB
Related parts for AD9985A/PCB
AD9985A/PCB Summary of contents
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FEATURES Variable analog input bandwidth control Variable SOGIN bandwidth control Automated clamping level adjustment 140 MSPS maximum conversion rate 300 MHz analog bandwidth 0 1.0 V analog input range 500 ps p-p PLL clock jitter at 110 MSPS ...
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AD9985A TABLE OF CONTENTS Specifications..................................................................................... 3 Explanation of Test Levels ........................................................... 6 Absolute Maximum Ratings............................................................ 7 ESD Caution.................................................................................. 7 Pin Configuration and Function Descriptions............................. 8 Design Guide................................................................................... 11 General Description................................................................... 11 Digital Inputs .............................................................................. 11 Input Signal Handling................................................................ 11 Hsync, ...
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SPECIFICATIONS 3.3 V, ADC clock = maximum conversion rate, unless otherwise noted Table 1. Parameter Temp RESOLUTION DC ACCURACY Differential Nonlinearity 25°C Full Integral Nonlinearity 25°C Full No Missing Codes Full ANALOG ...
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AD9985A Parameter Temp DIGITAL OUTPUTS Output Voltage, High (V ) Full OH Output Voltage, Low (V ) Full OL Duty Cycle DATACK Full Output Coding POWER SUPPLY V Supply Voltage Full D V Supply Voltage Full DD P Supply Voltage ...
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3.3 V, ADC clock = maximum conversion rate, unless otherwise noted Table 2. Parameter RESOLUTION DC ACCURACY Differential Nonlinearity Integral Nonlinearity ANALOG INPUT Input Voltage Range Minimum Maximum Gain Tempco Input Bias ...
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AD9985A Parameter POWER SUPPLY V Supply Voltage D V Supply Voltage DD P Supply Voltage VD I Supply Current ( Supply Current ( Supply Current ( Total Power ...
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ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Analog Inputs Digital Inputs Digital Output Current Operating Temperature Storage Temperature Maximum Junction Temperature Maximum Case Temperature ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 ...
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AD9985A PIN CONFIGURATION AND FUNCTION DESCRIPTIONS 1 GND GREEN <7> 2 GREEN <6> 3 GREEN <5> 4 GREEN <4> 5 GREEN <3> 6 GREEN <2> 7 GREEN <1> 8 GREEN <0> 9 GND BLUE <7> 12 ...
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Pin Type Mnemonic Function Power Supply V Analog Power Supply D V Output Power Supply DD PV PLL Power Supply D GND Ground Serial Port (2-Wire) SDA Serial Port Data I/O SCL Serial Port Data Clock (100 kHz maximum) A0 ...
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AD9985A Pin Description Data Outputs RED Data Output, Red Channel. GREEN Data Output, Green Channel. BLUE Data Output, Blue Channel. The main data outputs. Bit 7 is the MSB. The delay from pixel sampling time to output is fixed. When ...
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DESIGN GUIDE GENERAL DESCRIPTION The AD9985A is a fully integrated solution for capturing analog RGB signals and digitizing them for display on flat panel moni- tors or projectors. The circuit is ideal for providing a computer interface for HDTV monitors ...
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AD9985A black output (code 0x00) when the known black input is present. The offset then remains in place when other signal levels are processed, and the entire signal is shifted to eliminate offset errors. In most PC graphics systems, black ...
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ADC during the back porch of the input signals, the AD9985A can self-adjust to eliminate any offset errors in its own ADC channels, as well as any offset errors present on the incoming graphics or video ...
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AD9985A 100 110 120 130 140 150 FREQUENCY (MHz) Figure 7. Pixel Clock Jitter vs. Frequency The PLL characteristics are determined by ...
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Table 9. Recommended VCO Range and Charge Pump Current Settings for Standard Display Formats Standard Refresh Modes Resolution Rate VGA 640 × 480 SVGA 800 × 600 ...
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AD9985A COAST TIMING In most computer systems, the Hsync signal is provided continuously on a dedicated wire. In these systems, the Coast input and function are unnecessary and should not be used, and the pin should be permanently connected to ...
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SERIAL REGISTER MAP The AD9985A is initialized and controlled by a set of registers that determine the operating modes. An external controller is used to write and read the control registers through the two-line serial interface port. Table 10. ...
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AD9985A Write and Hexadecimal Read or Default Address Read-Only Bits Value *1****** **0***** ***0**** ****1*** *****1** ******1* 0x10 R/W 7:3 10111*** *****0** ******0* *******0 0x11 R/W 7:0 00100000 0x12 R/W 7:0 00000000 0x13 R/W 7:0 00000000 0x14 RO 7:0 0x15 ...
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Write and Hexadecimal Read or Default Address Read-Only Bits Value 0x16 R/W 7 0******* 6:5 *00***** 4 ***0**** 3:0 ****0000 0x17 RO 7:0 0x18 RO 7:0 0x19 R/W 7:0 00000100 0x1A R/W 7:0 00000100 0x1B R/W 7:0 00000100 0x1C 7:0 ...
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AD9985A The power-up default value of PLLDIV is 1693 (PLLDIVM = 0x69, PLLDIVL = 0xDx). The AD9985A updates the full divide ratio only when this register is written to. CLOCK GENERATOR CONTROL 03 7–6 VCO Range Select Two bits that ...
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Green Channel Gain Adjust (GREENGAIN) An 8-bit word that sets the gain of the green channel. See REDGAIN (08). 0A 7–0 Blue Channel Gain Adjust (BLUEGAIN) An 8-bit word that sets the gain of the blue channel. See ...
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AD9985A Table 16. Active Hsync Override Settings Override Result 0 Autodetermines the active interface (power-up default) 1 Override, Bit 3 determines the active interface 0E 3 Active Hsync Select This bit is used under two conditions used to ...
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Table 24. Coast Input Polarity Override Settings Override Result 0 Determined by chip (power-up default) 1 Determined by user 0F 3 Coast Input Polarity This bit indicates the polarity of the Coast signal that is applied to the PLL COAST ...
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AD9985A 14 7 Hsync Detect This bit is used to indicate when activity is detected on the Hsync input pin (Pin 30). If Hsync is held high or low, activity will not be detected. Table 31. Hsync Detection Results Detect ...
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Table 38. Detected Coast Input Polarity Status Polarity Status Result 0 Coast polarity negative 1 Coast polarity positive This indicates that Bit 1 of Register 5 is the 4:2:2 output mode select bit 4:2:2 Output Mode Select A ...
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AD9985A 2-WIRE SERIAL CONTROL PORT A 2-wire serial interface control interface is provided. Two AD9985A devices can be connected to the 2-wire serial interface; each device has a unique address. The 2-wire serial interface comprises a clock (SCL) and a ...
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Serial Interface Read/Write Examples Write to one control register: 1. Start signal 2. Slave address byte (R/ W Bit = low) 3. Base address byte 4. Data byte to base address 5. Stop signal Write to four consecutive control registers: ...
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AD9985A Table 46. Control of the Sync Block Muxes via the Serial Register Mux No. Serial Bus Control Bit 1 and 2 0x0E: Bit 3 3 0x0F: Bit 5 4 0x0E: Bit 0 SYNC SLICER The purpose of the sync ...
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PCB LAYOUT RECOMMENDATIONS The AD9985A is a high precision, high speed analog device. Consequently, to get the maximum performance out of the part important to have a board with a good layout. This section provides guidelines for designing ...
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AD9985A OUTPUTS (BOTH DATA AND CLOCKS) Try to minimize the trace length that the digital outputs have to drive. Longer traces have higher capacitance, which requires more current, which causes more internal digital noise. Shorter traces reduce the possibility of ...
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... OUTLINE DIMENSIONS 1.45 1.40 1.35 0.15 SEATING 0.05 PLANE VIEW A ROTATED 90° CCW ORDERING GUIDE Model 1 AD9985ABSTZ-110 1 AD9985AKSTZ-110 AD9985AKSTZ-140 1 AD9985A/PCB Pb-free part. 16.20 16.00 SQ 0.75 1.60 15.80 0.60 MAX 0. PIN 1 TOP VIEW (PINS DOWN) 0.20 0.09 7° 3.5° 20 0° ...
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AD9985A NOTES © 2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05484-0-7/05(0) Rev Page ...