AD7684 Analog Devices, AD7684 Datasheet
AD7684
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AD7684 Summary of contents
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... The reference voltage, REF, is applied externally and can be set up to the supply voltage. Its power scales linearly with throughput. The AD7684 is housed in an 8-lead MSOP, with an operating temperature specified from −40°C to +85°C. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. ...
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... Updated Outline Dimensions ....................................................... 15 Changes to Ordering Guide .......................................................... 15 Converter Operation.................................................................. 12 Transfer Functions ..................................................................... 12 Typical Connection Diagram ................................................... 13 Analog Inputs ............................................................................. 13 Driver Amplifier Choice ........................................................... 13 Voltage Reference Input ............................................................ 14 Power Supply............................................................................... 14 Digital Interface.......................................................................... 14 Layout .......................................................................................... 14 Evaluating the Performance of the AD7684............................... 14 Outline Dimensions ....................................................................... 15 Ordering Guide .......................................................................... 15 10/04— Revision 0: Initial Version Rev Page ...
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... REF REF 65 1 See the Analog Inputs section 10 100 2.9 VDD + 0.3 50 0.3 × VDD VDD + 0 Serial 16 bits twos complement 0.4 5.5 5.5 800 560 1.5 150 +85 AD7684 Unit Bits μs kSPS MHz V μ μA μ μA μ μW ...
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... AD7684 VDD = VDD −40°C to +85°C, unless otherwise noted. REF A Table 3. Parameter Conditions ACCURACY No Missing Codes Integral Linearity Error Transition Noise 1 Gain Error MIN MAX Gain Error Temperature Drift 1 Zero Error MIN MAX Zero Temperature Drift Power Supply Sensitivity VDD = 5 V ± ...
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... Symbol Min Typ Max t 100 CYC t 0 CSD t 20 SUCS HDO t 14 100 DIS 400 ACQ ACQ POWER DOWN t DIS Hi (LSB) 1.4V t DELAY 2V 0.8V 90% 10% AD7684 Unit kHz μ ...
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... AD7684 ABSOLUTE MAXIMUM RATINGS Table 6. Parameter Rating Analog Inputs 1 1 +IN , −IN GND − 0 VDD + 0 ±130 mA REF GND − 0 VDD + 0.3 V Supply Voltages VDD to GND −0 Digital Inputs to GND −0 VDD + 0.3 V Digital Outputs to GND −0 VDD + 0.3 V Storage Temperature Range − ...
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... Scale) GND Figure 6. 8-Lead MSOP Pin Configuration /2 and must be driven 180° out of phase with −IN. REF /2 and must be driven 180° out of phase with +IN. REF . When high, D OUT Rev Page AD7684 , REF and 0 V, REF is high impedance. OUT ...
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... AD7684 TERMINOLOGY Integral Nonlinearity Error (INL) Linearity error refers to the deviation of each individual code from a line drawn from negative full scale through positive full scale. The point used as negative full scale occurs ½ LSB before the first code transition. Positive full scale is defined as a level 1½ ...
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... Figure 10. Differential Nonlinearity vs. Code VDD = REF = 5V 123872 3050 4150 0 0 FFFB FFFC FFFD FFFE CODE IN HEX Figure 11. Histogram Input at the Code Center 0 16384 POINT FFT VDD = REF = 2. 100kSPS 20.43kHz FREQUENCY (kHz) Figure 12. FFT Plot AD7684 65536 0 FFFF 40 50 ...
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... AD7684 100 95 S/[N+D] 90 ENOB 85 80 2.0 2.5 3.0 3.5 4.0 REFERENCE VOLTAGE (V) Figure 13. SNR, SINAD, and ENOB vs. Reference Voltage 100 VREF = 5V, –10dB 95 VREF = 5V, –1dB 90 VREF = 2.5V, –1dB 100 FREQUENCY (kHz) Figure 14. SINAD vs. Frequency –80 –85 VREF = 2.5V, –1dB –90 –95 –100 VREF = 5V, –1dB –105 –110 – ...
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... ZERO ERROR 1 0 –1 –2 GAIN ERROR –3 –4 –5 –6 –55 –35 – TEMPERATURE (°C) Figure 19. Zero Error and Gain Error vs. Temperature 85 105 125 Rev Page AD7684 ...
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... The AD7684 provides the user with an on-chip, track-and-hold and does not exhibit any pipeline delay or latency, making it ideal for multiple, multiplexed channel applications. The AD7684 is specified from 2 5 housed in an 8-lead MSOP. CONVERTER OPERATION The AD7684 is a successive approximation ADC based on a charge redistribution DAC ...
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... AD7683 should be used. Figure 23 shows an equivalent circuit of the input structure of the AD7684. The two diodes, D1 and D2, provide ESD protection for the analog inputs, +IN and −IN. Care must be taken to ensure that the analog input signal never exceeds the supply rails by more than 0.3 V because this causes these diodes to become forward-biased and start conducting current ...
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... The pinout of the AD7684 with all its analog signals on the left side and all its digital signals on the right side eases this task. Avoid running digital lines under the device because these couple noise onto the die, unless a ground plane under the AD7684 is used as a shield ...
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... LSB maximum AD7684BRMZ 1 ±3 LSB maximum 1 AD7684BRMZRL7 ±3 LSB maximum 1, 2 EVAL-AD7684CBZ 1, 3 EVAL-CONTROL BRD3Z RoHS Compliant Part. 2 This board can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRDx for evaluation/demonstration purposes. 3 This board allows control and communicate with all the Analog Devices, Inc. evaluation boards ending in the CB designators. ...
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... AD7684 NOTES ©2004–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04302-0-10/07(A) Rev Page ...