AD7484 Analog Devices, AD7484 Datasheet
AD7484
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AD7484 Summary of contents
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... Therefore, if the analog input range strays outside the nominal range 8%, the user can still accurately resolve the signal by using the 15th bit. The AD7484 is powered 5.25 V supply. The part also provides a V pin that allows the user to set the voltage DRIVE levels for the digital interface lines ...
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... AD7484 TABLE OF CONTENTS Features .............................................................................................. 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Timing Characteristics ................................................................ 5 Absolute Maximum Ratings ............................................................ 6 ESD Caution .................................................................................. 6 Pin Configuration and Function Descriptions ............................. 7 Typical Performance Characteristics ............................................. 9 Terminology .................................................................................... 11 REVISION HISTORY 12/09—Rev Rev. C Changes to Table 1, Power Requirements Section ....................... 4 Changes to Ordering Guide .......................................................... 19 8/08— ...
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... V ±1 µ 220 µA +2.5 V ±50 mV ±100 mV 1 Ω Rev Page AD7484 to T and valid for V = 2.7 V MIN MAX DRIVE Test Conditions/Comments MHz MHz MHz, extended input MHz, internal reference IN Internal reference ...
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... AD7484 Parameter LOGIC INPUTS Input High Voltage, V INH Input Low Voltage, V INL Input Current Input Capacitance LOGIC OUTPUTS Output High Voltage Output Low Voltage Floating State Leakage Current Floating State Output Capacitance 4 Output Coding CONVERSION RATE Conversion Time ...
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... Rev Page AD7484 and valid for 5.25 V, MAX DRIVE Min Typ Max Unit 300 ns 100 ns 5 100 ...
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... AD7484 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter AV to AGND DGND DGND DRIVE Analog Input Voltage to AGND Digital Input Voltage to DGND REFIN to AGND Input Current to Any Pin Except Supply Pins Operating Temperature Range Commercial Storage Temperature Range Junction Temperature θ ...
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... AGND 6 TOP VIEW (Not to Scale) VIN 7 REFOUT 8 REFIN 9 10 REFSEL 11 AGND AGND Figure 2. Pin Configuration DRIVE Rev Page D10 DRIVE 31 DGND 30 DGND input. AD7484 ...
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... AD7484 Pin No. Mnemonic Description 40 D14 Data Output Bit for Overranging. If the overrange feature is not used, this pin should be pulled to DGND via a 100 kΩ resistor. 41 CONVST Convert Start Logic Input. A conversion is initiated on the falling edge of the CONVST signal. The input track- and-hold amplifier goes from track mode to hold mode, and the conversion process commences. ...
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... INPUT FREQUENCY (kHz) Figure 7. SINAD vs. Input Tone (AD8021 Input Circuit) –40 200Ω 100Ω –50 –60 51Ω –70 10Ω –80 0Ω –90 100 1000 INPUT FREQUENCY (kHz) Figure 8. THD vs. Input Tone for Different Input Resistances AD7484 16384 10000 10000 ...
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... AD7484 0 100mV p-p SINE WAVE ON SUPPLY PINS –10 –20 –30 –40 –50 –60 –70 –80 10 100 FREQUENCY (kHz) Figure 9. PSRR Without Decoupling 0.0004 0 –0.0004 –0.0008 –0.0012 –0.0016 –0.0020 –55 –25 1000 Rev Page 125 TEMPERATURE (° ...
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... The AD7484 is tested using the CCIF standard where two input frequencies near the top end of the input bandwidth are used. /2), excluding dc. The ...
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... ADC, and versatile interface logic functions on a single chip. The normal analog input signal range that the AD7484 can convert 2 using the offset and overrange features on the ADC, the AD7484 can convert analog input signals from −200 mV to +2.7 V while operating from a single 5 V supply ...
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... The internal reference cannot be used in conjunction with the nap mode. If the AD7484 is put into nap mode after each conversion, the average power dissipation is reduced, but the throughput rate is limited by the power-up time. Using the AD7484 with a through- ...
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... Initiating a conversion before the required power-up time has elapsed results in incorrect conversion data external reference source is used and kept powered up while the AD7484 is in standby mode, the power-up time required is reduced to 80 µs. OFFSET/OVERRANGE The AD7484 provides a ± ...
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... CLIP tied to logic high. The combined advantages of the offset and overrange features of the AD7484 are shown in Table 6. Table 6 shows the same range of analog input and offset values as Table 5 but with the clipping feature disabled. ...
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... For this reason, if operating the AD7484 at throughput speeds greater than 2.5 MSPS necessary to tie both the CS pin and RD pin on the AD7484 low and use a buffer on the data lines. This situation may also arise in the case where a read operation cannot be completed in the time after the end of one conversion and the start of the quiet period before the next conversion ...
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... Figure 23.The decoupling capacitors are close to the supply pins as possible. This is made easier by the use of multilayer boards. The signal traces from the AD7484 pins can be run on the top layer, while the Figure 24. Top Layer Routing Figure 25. Bottom Layer Silkscreen Figure 26 ...
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... AD7484 CONVST BUSY CS RD D[14:0] CONVST CS RD WRITE D[14:0] CONVST BUSY D[14:0] CONVST BUSY D[14:0] t CONV DATA VALID Figure 29. Parallel Mode READ Cycle OFFSET DATA Figure 30. Parallel Mode WRITE Cycle t CONV DATA N – ...
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... VIEW A 0.50 COPLANARITY BSC LEAD PITCH COMPLIANT TO JEDEC STANDARDS MS-026-BBC Figure 33. 48-Lead Plastic Quad Flatpack (LQFP) [ST-48] Dimensions shown in millimeters Package Description 48-Lead Plastic Quad Flatpack Package (LQFP) Evaluation Board Controller Board 3 Rev Page 7.20 7. 0.27 0.22 0.17 Package Option ST-48 2 AD7484 ...
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... AD7484 NOTES ©2002–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02642-0-12/09(C) Rev Page ...