AD5934YRSZ Analog Devices Inc, AD5934YRSZ Datasheet
AD5934YRSZ
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AD5934YRSZ Summary of contents
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FEATURES Programmable output peak-to-peak excitation voltage to a maximum frequency of 100 kHz Programmable frequency sweep capability with 2 serial I C interface Frequency resolution of 27 bits (<0.1 Hz) Impedance measurement range from 1 kΩ MΩ Capable ...
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AD5934 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 3 Specifications..................................................................................... Serial Interface Timing Characteristics .............................. 6 Absolute Maximum Ratings............................................................ 7 ESD Caution.................................................................................. 7 ...
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REVISION HISTORY 5/8—Rev Rev. A Changes to Layout.............................................................. Universal Changes to Features Section, General Description Section, and Figure 1 ...............................................................................................1 Deleted Table 1; Renumbered Sequentially ...................................1 Changes to Table 1 ............................................................................4 Changes to Table 2 ............................................................................6 Changes to ...
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AD5934 SPECIFICATIONS VDD = 3.3 V, MCLK = 16.776 MHz p-p output excitation voltage @ 30 kHz, 200 kΩ connected between Pin 5 and Pin 6; feedback resistor = 200 kΩ connected between Pin 4 and Pin 5; ...
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Parameter RECEIVE STAGE Input Leakage Current 5 Input Capacitance Feedback Capacitance ANALOG-TO-DIGITAL CONVERTER Resolution Sampling Rate LOGIC INPUTS Input High Voltage Input Low Voltage Input Current Input Capacitance POWER REQUIREMENTS VDD I ...
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AD5934 SERIAL INTERFACE TIMING CHARACTERISTICS VDD = 2 5.5 V; all specifications T Table 2. 1 Parameter Limit MIN MAX f 400 SCL 1.3 ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter DVDD to GND AVDD1 to GND AVDD2 to GND SDA/SCL to GND VOUT to GND VIN to GND MCLK to GND Operating Temperatures Extended Industrial Range (Y ...
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AD5934 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description Connect. 4 RFB External Feedback Resistor. Connect from Pin 4 to Pin 5. This pin sets the gain of ...
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TYPICAL PERFORMANCE CHARACTERISTICS 35 MEAN = 1.9824 SIGMA = 0.0072 1.92 1.94 1.96 1.98 2.00 VOLTAGE (V) Figure 4. Range 1 Output Excitation Voltage Distribution, VDD = 3 MEAN = 1.4807 ...
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AD5934 30 MEAN = 0.1982 SIGMA = 0.0008 0.192 0.194 0.196 0.198 0.200 VOLTAGE (V) Figure 10. Range 4 Output Excitation Voltage Distribution, VDD = 3 MEAN = 0.1792 SIGMA = 0.0024 ...
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TEMINOLOGY Total System Accuracy The AD5934 can accurately measure a range of impedance values to less than 0.5% of the correct impedance value for supply voltages between 2 5.5 V. Spurious-Free Dynamic Range (SFDR) Along with the frequency ...
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AD5934 SYSTEM DESCRIPTION MCLK SCL MICROCONTROLLER INTERFACE SDA REAL REGISTER MAC CORE (1024 DFT) WINDOWING OF DATA The AD5934 is a high precision, impedance converter system solution that combines an on-board frequency generator with a 12-bit, 250 kSPS ADC. The ...
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TRANSMIT STAGE As shown in Figure 16, the transmit stage of the AD5934 is made 27-bit phase accumulator DDS core that provides the output excitation signal at a particular frequency. The input to the phase accumulator is ...
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AD5934 FREQUENCY SWEEP COMMAND SEQUENCE The following sequence must be followed to implement a frequency sweep: 1. Enter standby mode. Prior to issuing a start frequency sweep command, the device must be placed in standby mode by issuing an enter ...
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IMPEDANCE CALCULATION MAGNITUDE CALCULATION The first step in the impedance calculation for each frequency point is to calculate the magnitude of the DFT at that point. The DFT magnitude is given Magnitude R I where: ...
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AD5934 2-POINT CALIBRATION Alternatively possible to minimize this error by assuming that the frequency variation is linear and adjusting the gain factor with a 2-point calibration. Figure 19 shows an impedance profile based on a 2-point gain factor ...
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GAIN FACTOR TEMPERATURE VARIATION The typical impedance error variation with temperature is in the order of 30 ppm/°C. Figure 21 shows an impedance profile with a variation in temperature for 100 kΩ impedance using a 2-point gain factor calibration. 101.5 ...
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AD5934 Impedance Range 3 (10 kΩ to 100 kΩ) The following conditions were used to conduct the tests shown in Figure 24: Output excitation voltage = 2 V p-p Calibration impedance value, Z CALIBRATION PGA gain = ×1 Supply voltage ...
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MEASURING THE PHASE ACROSS AN IMPEDANCE The AD5934 returns a complex output code made separate real and imaginary components. The real component is stored at Register Address 0x94 and Register Address 0x95, and the imaginary component is ...
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AD5934 200 180 160 220kΩ RESISTOR 140 120 100 80 60 10pF CAPACITOR 15k 30k 45k 60k 75k FREQUENCY (Hz) Figure 28. System Phase Response vs. Capacitive Phase The phase difference (that is, ZØ) between the ...
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PERFORMING A FREQUENCY SWEEP RESET: BY ISSUING A RESET COMMAND TO THE CONTROL REGISTER, THE DEVICE IS PLACED IN STANDBY MODE. PROGRAM FREQUENCY SWEEP PARAMETERS INTO RELEVANT REGISTERS (1) START FREQUENCY REGISTER (2) NUMBER OF INCREMENTS REGISTER (3) FREQUENCY INCREMENT ...
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AD5934 REGISTER MAP Table 7. Register Name Control Start Frequency Frequency Increment Number of Increments Number of Settling Time Cycles Status Real Data Imaginary Data CONTROL REGISTER (REGISTER ADDRESS 0x80, REGISTER ADDRESS 0x81) The AD5934 contains a 16-bit control register ...
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Control Register Decode Initialize with Start Frequency This command enables the DDS to output the programmed start frequency for an indefinite time. Initially used to excite the unknown impedance. When the output unknown impedance has settled after a ...
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AD5934 NUMBER OF INCREMENTS REGISTER (REGISTER ADDRESS 0x88, REGISTER ADDRESS 0x89) The default value of the number of increments register upon reset is as follows are not reset at power-up. After a reset command, the contents of ...
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Valid Real/Imaginary Data This bit is set when data processing for the current frequency point is finished, indicating real/imaginary data available for reading. The bit is reset when a start frequency sweep/increment frequency/repeat frequency DDS command is issued. In addition, ...
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AD5934 SERIAL BUS INTERFACE Control of the AD5934 is carried out via the I serial interface protocol. The AD5934 is connected to this bus as a slave device under the control of a master device. The AD5934 has a 7-bit ...
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WRITING/READING TO THE AD5934 2 The I C interface specification defines several different protocols for different types of read and write operations. This section describes the protocols used in the AD5934. The figures in this section use the abbreviations shown ...
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AD5934 READ OPERATIONS 2 The AD5934 uses two I C read protocols: the receive byte and the block read. Receive Byte In the AD5934, the receive byte protocol is used to read a single byte of data from a register ...
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TYPICAL APPLICATIONS MEASURING SMALL IMPEDANCES The AD5934 is capable of measuring impedance values MΩ if the system gain settings are chosen correctly for the impedance subrange of interest. If the user places a small impedance value (≤500 ...
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AD5934 For example, if the user measures Z UNKNOWN have a small impedance value within the range of 90 Ω to 110 Ω over the frequency range of 30 kHz to 32 kHz, the user may not ...
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SENSOR/COMPLEX IMPEDANCE MEASUREMENT The operational principle of a capacitive proximity sensor is based on the change of a capacitance in a RLC resonant circuit. This leads to changes in the resonant frequency of the RLC circuit, which can be evaluated ...
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AD5934 CHOOSING A REFERENCE FOR THE AD5934 To achieve the best performance from the AD5934, carefully choose the precision voltage reference. The AD5934 has three reference inputs: AVDD1, AVDD2, and DVDD. The voltage on these reference inputs should be run ...
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LAYOUT AND CONFIGURATION POWER SUPPLY BYPASSING AND GROUNDING When accuracy is important in a circuit, carefully consider the power supply and ground return layout on the board. The printed circuit board (PCB) containing the AD5934 should have separate analog and ...
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AD5934 EVALUATION BOARD The AD5934 evaluation board allows designers to evaluate the high performance AD5934 impedance converter with minimum effort. The evaluation board interfaces to the USB port possible to power the entire board from ...
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SCHEMATICS Figure 40. EVAL-AD5934EBZ USB Schematic Rev Page AD5934 05325-144 ...
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AD5934 Figure 41. EVAL-AD5934EBZ Schematic Rev Page 05325-145 ...
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Figure 42. Linear Regulator on EVAL-AD5934EBZ Rev Page AD5934 05325-146 ...
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AD5934 Figure 43. Decoupling on the EVAL-AD5934EBZ Rev Page 05325-147 ...
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... FEC 9341501 4 Not inserted 4 Not inserted 1 FEC 9330402 FEC 9331662 1 1 FEC 9330810 FEC 9330399 1 1 FEC 9332383 1 FEC 9330771 1 FEC 8731128 1 FEC 1111349 Not Inserted 1 FEC 9758070 Digi-Key 428-1669-ND ADR425ARZ ADP3303ARZ-3.3 AD5933YRSZ/AD5934YRSZ 1 FEC 9509658 AEL-4313 1 FEC 651813 1 FEC 522764 Digi-Key 167-1011-ND ...
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... MAX 0.05 MIN COPLANARITY 0.10 ORDERING GUIDE Model Temperature Range 1 AD5934YRSZ −40°C to +125°C AD5934YRSZ-REEL7 1 −40°C to +125°C 1 EVAL-AD5934EBZ −40°C to +125° RoHS Compliant Part. 2 Purchase of licensed I C components of Analog Devices or one of its sublicensed Associated Companies conveys a license for the purchaser under the Philips I ...