AD7760BSVZ Analog Devices Inc, AD7760BSVZ Datasheet
AD7760BSVZ
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AD7760BSVZ Summary of contents
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FEATURES 120 dB dynamic range at 78 kHz output data rate 100 dB dynamic range at 2.5 MHz output data rate 112 dB SNR at 78 kHz output data rate 100 dB SNR at 2.5 MHz output data rate 2.5 ...
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AD7760 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 3 Specifications..................................................................................... 4 Timing Specifications .................................................................. 6 Timing Diagrams.......................................................................... 7 Absolute Maximum Ratings............................................................ 8 ESD Caution.................................................................................. 8 Pin Configuration ...
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REVISION HISTORY 8/06—Rev Rev. A Updated Package Option................................................... Universal Change to Features............................................................................1 Changes to Specifications.................................................................4 Changes to Absolute Maximum Ratings........................................8 Changes to Terminology Section ..................................................11 Added Figure 36 Through Figure 39 ............................................17 Added Modulator Data Output Mode Section ...
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AD7760 SPECIFICATIONS 2 DRIVE DD the on-chip amplifier with components as shown in Table 8, unless otherwise noted. Table 2. Parameter DYNAMIC PERFORMANCE Decimate by 256 ...
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Parameter ANALOG INPUT Differential Input Voltage Input Capacitance REFERENCE INPUT/OUTPUT V Input Voltage REF V Input DC Leakage Current REF V Input Capacitance REF POWER DISSIPATION Total Power Dissipation Standby Mode POWER REQUIREMENTS AV 1 (Modulator Supply ...
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AD7760 TIMING SPECIFICATIONS 2 DRIVE DD Table 3. Parameter Limit MIN MAX f 1 MCLK 40 f 500 ICLK ...
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TIMING DIAGRAMS DRDY CS RD/WR D[0:15] CS RD/ D[0:15 DATA MSW Figure 2. Filtered Output—Parallel Interface Timing Diagram REGISTER ADDRESS ...
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AD7760 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 4. Parameters GND GND GND GND DRIVE – to ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS DGND MCLKGND MCLK AV AGND2 AV AGND1 DECAPA REFGND V AGND4 AV AGND2 AV AV AGND2 Table 5. Pin Function Descriptions Pin No. Mnemonic Description 2.5 V Power Supply for Modulator. ...
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AD7760 Pin No. Mnemonic Description 30 DECAPB Decoupling Pin capacitor must be inserted between this pin and AGND3 Bias Current Setting Pin. A resistor must be inserted between this pin and AGND. For more details, ...
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TERMINOLOGY Signal-to-Noise Ratio (SNR) SNR is the ratio of the rms value of the actual input signal to the rms sum of all other spectral components below the Nyquist frequency, excluding harmonics and dc. The value for SNR is expressed ...
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AD7760 TYPICAL PERFORMANCE CHARACTERISTICS 2 DRIVE DD FFTs are generated from 65,536 samples using a 7-term Blackman-Harris window. 0 –25 –50 –75 –100 –125 –150 –175 ...
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FREQUENCY (kHz) Figure 11. Normal Mode FFT, 100 kHz, −0.5 dB Input Tone, 8× Decimation 0 –25 –50 –75 –100 –125 –150 –175 –200 0 250 500 ...
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AD7760 0 –25 –50 –75 –100 –125 –150 –175 –200 0 250 500 750 FREQUENCY (kHz) Figure 17. Normal Mode FFT, 1 MHz, −6 dB Input Tone, 8× Decimation 0 TONE A: 999.75kHz –25 TONE B: 1.00025MHz –50 –75 –100 ...
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TONE A: 999.75kHz TONE B: 1.00025MHz –20 THIRD-ORDER IMD: –89.15dB –40 –60 –80 –100 –120 –140 –160 995 997 999 1001 FREQUENCY (kHz) Figure 23. Normal Mode IMD, 1 MHz Center Frequency, 8× Decimation 100.5 NORMAL MODE 100.0 99.5 ...
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AD7760 4500 4000 3500 3000 2500 2000 1500 1000 500 0 8385222 8385238 8385254 24-BIT CODE Figure 29. Normal Mode, 24-Bit Histogram, 256× Decimation 600 500 400 300 200 100 0 8385016 8385116 8385216 8385316 24-BIT CODE Figure 30. Normal ...
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CODE Figure 35. 24-Bit DNL ICLK FREQUENCY (MHz) Figure 36. AI ...
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AD7760 THEORY OF OPERATION The AD7760 employs a Σ-Δ conversion technique to convert the analog input into an equivalent digital word. The modulator samples the input waveform and outputs an equivalent digital word to the digital filter at a rate ...
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MODULATOR DATA OUTPUT MODE Operating the AD7760 in modulator output mode enables the output of data directly from the Σ-Δ modulator. This mode of operation bypasses the AD7760 on-board digital filtering capabilities, outputting data in its unfiltered form. As discussed ...
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AD7760 MODULATOR DATA OUTPUT MODE INTERFACE The AD7760 can be configured in modulator data output mode (bypassing the default decimation filtering) by writing 0 to each of the bits contained in Control Register 1: BYP F1 , BYP F3 , ...
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DRDY D[0:15] MCLK t 11 CS, RD/WR In the case where odd number of MCLK cycles, the modulator data output on Pins D [15:0] is output on the rising edge of DRDY . In this case, the ...
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AD7760 AD7760 INTERFACE READING DATA When the AD7760 is outputting data MHz output data rate or less, the interface operates in a conventional mode, as shown in Figure 2, using a 16-bit bidirectional parallel interface. This interface ...
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WRITING TO THE AD7760 There are many features and parameters that the user can change by writing to the AD7760 device. See the Using the AD7760 section, which details the writing sequence needed to initialize the operation of the part. ...
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AD7760 CLOCKING THE AD7760 The AD7760 requires an external low jitter clock source. This signal is applied to the MCLK pin, and the MCLKGND pin is used to sense the ground from the clock source. An internal clock signal (ICLK) ...
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Figure 48. Maximum Slew Rate of Sine Wave with Amplitude p-p 1.0 0.5 0 –0.5 –1.0 Figure 49. Maximum Slew Rate of Sine Wave (with the Same Frequency as in Figure 48) ...
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AD7760 DRIVING THE AD7760 The AD7760 has an on-chip differential amplifier that operates with a supply voltage (AV 3) within the 3. 5.25 V range. DD For a 4.096 V reference, the supply voltage must ...
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To obtain maximum performance from the AD7760 advisable to drive the ADC with differential signals. Figure 53 shows how a bipolar, single-ended signal biased around ground can drive the AD7760 with the use of an external op amp, ...
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AD7760 DECOUPLING AND LAYOUT RECOMMENDATIONS Due to the high performance nature of the AD7760, correct decoupling and layout techniques are required to obtain the performance as stated within this data sheet. Figure 55 shows a simplified connection diagram for the ...
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SUPPLY DECOUPLING Every supply pin must be connected to the appropriate supply via a ferrite bead and decoupled to the correct ground pin with a 100 nF, 0603 case size, X7R dielectric capacitor. There are two exceptions to this: • ...
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AD7760 PROGRAMMABLE FIR FILTER As previously mentioned, the third FIR filter on the AD7760 is user programmable. The default coefficients that are loaded upon reset are given in Table 10, and the frequency responses are shown in Figure 57. The ...
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DOWNLOADING A USER-DEFINED FILTER As previously mentioned, the filter coefficients are 27 bits in length—one sign and 26 magnitude bits. Because the AD7760 has a 16-bit parallel bus, the coefficients are padded with 5 MSB 0s to generate a 32-bit ...
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AD7760 Table 13 shows the hexadecimal values (in sign-and-magnitude format) that are downloaded to the AD7760 to realize this filter. The table is also split into the bytes that are summed to produce the checksum. The checksum generated from these ...
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AD7760 REGISTERS The AD7760 has a number of user-programmable registers. The control registers are used to set the decimation rate, the filter configuration, the clock divider, and so on. There are also digital gain, offset, and overrange threshold registers. Writing ...
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AD7760 STATUS REGISTER (READ ONLY) MSB D15 D14 D13 D12 D11 PART 1 PART 0 DIE 2 DIE 1 DIE 0 Table 17. Bit Descriptions of Status Register Bit Mnemonic Comment 15, 14 PART [1:0] Part Number. These bits are ...
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... SEATING 0.05 0.08 MAX PLANE COPLANARITY VIEW A ROTATED 90 ° CCW ORDERING GUIDE Model Temperature Range 1 AD7760BSVZ −40°C to +85°C 1 AD7760BSVZ-REEL −40°C to +85°C EVAL-AD7760EB Pb-free part. 12.20 12.00 SQ 1.20 11.80 MAX PIN 1 TOP VIEW (PINS DOWN) ...
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AD7760 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04975-0-8/06(A) Rev Page ...