EVAL-AD7654CB Analog Devices Inc, EVAL-AD7654CB Datasheet
EVAL-AD7654CB
Specifications of EVAL-AD7654CB
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EVAL-AD7654CB Summary of contents
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FEATURES Dual, 16-bit, 2-channel simultaneous sampling ADC 16-bit resolution with no missing codes Throughput: 500 kSPS (normal mode) 444 kSPS (impulse mode) INL: ±3.5 LSB max (±0.0053% of full scale) SNR typ @ 100 kHz THD: −100 dB ...
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... Serial Interface ............................................................................ 20 Master Serial Interface............................................................... 20 Slave Serial Interface .................................................................. 22 Microprocessor Interfacing....................................................... 24 SPI Interface (ADSP-219x) ....................................................... 24 Application Hints ........................................................................... 25 Layout .......................................................................................... 25 Evaluating the AD7654 Performance ...................................... 25 Outline Dimensions ....................................................................... 26 Ordering Guide .......................................................................... 27 11/04—Rev Rev. A Changes to Figure 7........................................................................ 12 Changes to Figure 18...................................................................... 15 Changes to Figure 19...................................................................... 16 Changes to Voltage Reference Input Section .............................. 17 Changes to Conversion Control Section ...
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SPECIFICATIONS AVDD = DVDD = 5 V, OVDD = 2 5.25 V; all specifications T Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Common-Mode Input Voltage Analog Input CMRR Input Current 1 Input Impedance THROUGHPUT SPEED Complete Cycle ...
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AD7654 Parameter DIGITAL OUTPUTS 6 Data Format 7 Pipeline Delay POWER SUPPLIES Specified Performance AVDD DVDD OVDD 9 Operating Current AVDD DVDD OVDD Power Dissipation 11 TEMPERATURE RANGE Specified Performance 1 See the Analog Inputs section. ...
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TIMING SPECIFICATIONS AVDD = DVDD = 5 V, OVDD = 2 5.25 V; all specifications T Table 3. Parameter CONVERSION AND RESET (See Figure 22 and Figure 23) Convert Pulse Width Time Between Conversions (Normal Mode/Impulse Mode) CNVST ...
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AD7654 Parameter SLAVE SERIAL INTERFACE MODES (see Figure 32 and Figure 33) External SCLK Setup Time External SCLK Active Edge to SDOUT Delay SDIN Setup Time SDIN Hold Time External SCLK Period External SCLK High External SCLK Low 1 In ...
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ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Values Analog Inputs 1 1 INAx , INBx , REFx, INxN, AVDD + 0 REFGND AGND − 0.3 V Ground Voltage Differences AGND, DGND, OGND ±0.3 V Supply Voltages AVDD, DVDD, OVDD ...
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AD7654 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions 1 Pin No. Mnemonic Type Description 1, 47, 48 AGND P Analog Power Ground Pin. 2 AVDD P Input Analog Power Pin. Nominally Multiplexer ...
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Pin No. Mnemonic Type Description 15 D[6] DI/O When SER/PAR is LOW, this output is used as Bit 6 of the parallel port data output bus. or INVSCLK When SER/PAR is HIGH, this input, part of the serial port, ...
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AD7654 1 Pin No. Mnemonic Type Description 35 CNVST DI Start Conversion. A falling edge on CNVST puts the internal sample-and-hold into the hold state and initiates a conversion. In impulse mode (IMPULSE = HIGH), if CNVST is held LOW ...
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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 ...
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AD7654 TYPICAL PERFORMANCE CHARACTERISTICS –1 –2 –3 –4 –5 0 16384 32768 CODE Figure 5. Integral Nonlinearity vs. Code 8000 7288 7220 7000 6000 5000 4000 3000 2000 953 903 1000 ...
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SNR 90 SINAD 85 ENOB 100 FREQUENCY (kHz) Figure 11. SNR, SINAD, and ENOB vs. Frequency –60 –50 –40 –30 –20 INPUT LEVEL (dB) Figure 12. SNR and SINAD ...
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AD7654 APPLICATION INFORMATION CIRCUIT INFORMATION The AD7654 is a very fast, low power, single-supply, precise, simultaneous sampling 16-bit ADC. The AD7654 provides the user with two on-chip, track-and- hold, successive approximation ADCs that do not exhibit any pipeline or latency, ...
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ANALOG SUPPLY (5V) + 10µF AD780 2.5V REF 1MΩ REF 50kΩ 1µF NOTE 1 100nF NOTE 2 NOTE 3 50Ω – 10Ω NOTE 4 U1 ANALOG INPUT A1 + 2.7nF C C NOTE 5 50Ω – 10Ω U2 ...
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AD7654 TYPICAL CONNECTION DIAGRAM Figure 18 shows a typical connection diagram for the AD7654. Different circuitry shown on this diagram is optional and is discussed in the following sections. ANALOG INPUTS Figure 19 shows a simplified analog input section of ...
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The AD8021 meets these requirements and is usually appro- priate for almost all applications. The AD8021 needs an external compensation capacitor of 10 pF. This capacitor should have good linearity as an NPO ceramic or mica type. The AD8022 could ...
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AD7654 1000 NORMAL 100 IMPULSE SAMPLING RATE (kSPS) Figure 21. Power Dissipation vs. Sample Rate CONVERSION CONTROL Figure 22 shows the detailed timing diagrams of the conversion process. The AD7654 is controlled by the signal ...
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CNVST t 16 BUSY EOC t 10 DATA PREVIOUS CHANNEL B PREVIOUS CHANNEL A BUS OR NEW Figure 24. Master Parallel Data Timing for Continuous Read ...
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AD7654 SERIAL INTERFACE The AD7654 is configured to use the serial interface when the SER/ PAR is held high. The AD7654 outputs 32 bits of data, MSB first, on the SDOUT pin. The order of the channels being output is ...
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EXT/INT = 0 CS, RD CNVST BUSY t 3 EOC SYNC SCLK SDOUT Figure 29. Master Serial Data Timing ...
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AD7654 SLAVE SERIAL INTERFACE External Clock The AD7654 is configured to accept an externally supplied serial data clock on the SCLK pin when the EXT/ INT pin is held high. In this mode, several methods can be used to read ...
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EXT/INT = 1 CS EOC BUSY SCLK SDOUT X D15 D14 SDIN D15 ...
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AD7654 MICROPROCESSOR INTERFACING The AD7654 is ideally suited for traditional dc measurement applications supporting a microprocessor and for ac signal processing applications interfacing to a digital signal processor. The AD7654 is designed to interface with either a parallel 8-bit wide ...
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... EVALUATING THE AD7654 PERFORMANCE A recommended layout for the AD7654 is outlined in the documentation of the evaluation board for the EVAL-AD7654CB. The evaluation board package includes a fully assembled and tested evaluation board, documentation, and software for controlling the board from a PC via the EVAL-CONTROL-BRD3 ...
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AD7654 OUTLINE DIMENSIONS 1.45 1.40 1.35 0.15 SEATING 0.05 PLANE VIEW A ROTATED 90° CCW 7.00 BSC SQ PIN 1 INDICATOR TOP VIEW 1.00 12° MAX 0.85 0.80 SEATING PLANE 0.75 1.60 0.60 MAX 0.45 0.20 0.09 7° 3.5° 0° ...
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... AD7654ASTRL –40°C to +85°C 1 AD7654ASTZ –40°C to +85°C AD7654ASTZRL 1 –40°C to +85°C 2 EVAL-AD7654CB 3 EVAL-CONTROL BRD2 3 EVAL-CONTROL BRD3 free part. 2 This board can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL-BRD2/EVAL-CONTROL-BRD3 for evaluation/demonstration purposes. ...
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AD7654 NOTES © 2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C03057–0–11/05(B) Rev Page ...