AD5933YRSZ Analog Devices Inc, AD5933YRSZ Datasheet
AD5933YRSZ
Specifications of AD5933YRSZ
Q2204656A
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AD5933YRSZ 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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AD5933 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 ...
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REVISION HISTORY 8/10—Rev Rev. C Changes to Impedance Error Section ........................................... 19 Changes to Figure 45 ...................................................................... 38 Changes to U4 Description in Table 19 ........................................ 42 2/10—Rev Rev. B Changes to General Description ..................................................... 1 ...
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AD5933 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 6 Input Capacitance Feedback Capacitance ( ANALOG-TO-DIGITAL CONVERTER 6 Resolution Sampling Rate TEMPERATURE SENSOR Accuracy Resolution Temperature Conversion Time LOGIC INPUTS Input High Voltage ( Input Low Voltage (V ) ...
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AD5933 SERIAL INTERFACE TIMING CHARACTERISTICS VDD = 2 5.5 V. All specifications T Table 2. 2 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 Rating DVDD to GND −0 +7.0 V AVDD1 to GND −0 +7.0 V AVDD2 to GND −0 +7.0 V SDA/SCL to ...
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AD5933 PIN CONFIGURATION AND DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description Connect. 4 RFB External Feedback Resistor. Connected from Pin 4 to Pin 5 and used to set 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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AD5933 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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N = 106 MEAN = 16.8292 0.142904 TEMP = –40° 16.4 16.6 16.8 17.0 OSCILLATOR FREQUENCY (MHz) Figure 14. Frequency Distribution of Internal Oscillator at −40° 100 MEAN ...
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AD5933 TERMINOLOGY Total System Accuracy The AD5933 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 ...
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SYSTEM DESCRIPTION MCLK OSCILLATOR SCL MICROCONTROLLER INTERFACE SDA REAL REGISTER MAC CORE (1024 DFT) WINDOWING OF DATA The AD5933 is a high precision impedance converter system solution that combines an on-board frequency generator with a 12-bit, 1 MSPS ADC. The ...
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AD5933 TRANSMIT STAGE As shown in Figure 19, the transmit stage of the AD5933 is made 27-bit phase accumulator DDS core that provides the output excitation signal at a particular frequency. The input to the phase accumulator ...
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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 a standby mode by issuing an enter ...
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AD5933 SYSTEM CLOCK The system clock for the AD5933 can be provided in one of two ways. The user can provide a highly accurate and stable system clock at the external clock pin (MCLK). Alternatively, the AD5933 provides an internal ...
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IMPEDANCE CALCULATION MAGNITUDE CALCULATION The first step in 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: R ...
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AD5933 TWO-POINT CALIBRATION Alternatively possible to minimize this error by assuming that the frequency variation is linear and adjusting the gain factor with a two-point calibration. Figure 23 shows an impedance profile based on a two-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 25 shows an impedance profile with a variation in temperature for 100 kΩ impedance using a two-point gain factor calibration. 101.5 ...
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AD5933 Impedance Range 3 (10 kΩ to 100 kΩ) The following conditions were used to conduct the test, as shown in Figure 28: Output excitation voltage = 2 V p-p Calibration impedance value, Z CALIBRATION PGA gain = ×1 Supply ...
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MEASURING THE PHASE ACROSS AN IMPEDANCE The AD5933 returns a complex output code made up of sepa- rate 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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AD5933 A plot showing the AD5933 system phase response calculated using a 220 kΩ calibration resistor (R FB and the repeated phase measurement with capacitive impedance is shown in Figure 32. One important point to note about ...
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PERFORMING A FREQUENCY SWEEP RESET: BY ISSUING A RESET COMMAND TO 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 REGISTER ...
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AD5933 REGISTER MAP Table 8. Register Name 0x80 Control 0x81 0x82 Start frequency 0x83 0x84 0x85 Frequency increment 0x86 0x87 0x88 Number of increments 0x89 0x8A Number of settling time cycles 0x8B 0x8F Status 0x92 Temperature data 0x93 0x94 Real ...
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Table 11. Control Register Map (D11 D0) Bits Description D11 No operation D8 PGA gain × ×1 D7 Reserved; set Reserved; set Reserved; set Reset ...
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AD5933 FREQUENCY INCREMENT REGISTER (REGISTER ADDRESS 0x85, REGISTER ADDRESS 0x86, REGISTER ADDRESS 0x87) The default value upon reset is as follows: D23 to D0 are not reset on power-up. After a reset command, the contents of this register are not ...
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STATUS REGISTER (REGISTER ADDRESS 0x8F) The status register is used to confirm that particular measure- ment tests have been successfully completed. Each of the bits from indicates the status of a specific functionality of the AD5933. Bit ...
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AD5933 SERIAL BUS INTERFACE Control of the AD5933 is carried out via the I serial interface protocol. The AD5933 is connected to this bus as a slave device under the control of a master device. The AD5933 has a 7-bit ...
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WRITING/READING TO THE AD5933 The interface specification defines several different protocols for different types of read and write operations. This section describes the protocols used in the AD5933. The figures in this section use the abbreviations shown in Table 15. ...
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AD5933 READ OPERATIONS 2 The AD5933 uses two I C read protocols: receive byte and block read. Receive Byte In the AD5933, the receive byte protocol is used to read a single byte of data from a register address whose ...
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TYPICAL APPLICATIONS MEASURING SMALL IMPEDANCES The AD5933 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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AD5933 The key point is that the output impedance of the external amplifier in Figure 41 (which is also in series with Z has a far less significant effect on gain factor calibration and subsequent impedance readings in comparison to ...
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BIOMEDICAL: NONINVASIVE BLOOD IMPEDANCE MEASUREMENT When a known strain of a virus is added to a blood sample that already contains a virus, a chemical reaction takes place whereby the impedance of the blood under certain conditions changes. By characterizing ...
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AD5933 ELECTRO-IMPEDANCE SPECTROSCOPY The AD5933 has found use in the area of corrosion monitoring. Corrosion of metals, such as aluminum and steel, can damage industrial infrastructures and vehicles such as aircraft, ships, and cars. This damage, if left unattended, may ...
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CHOOSING A REFERENCE FOR THE AD5933 To achieve the best performance from the AD5933, carefully choose the precision voltage reference. The AD5933 has three reference inputs: AVDD1, AVDD2, and DVDD recom- mended that the voltage on these reference ...
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AD5933 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 containing the AD5933 should have separate analog and ...
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EVALUATION BOARD The AD5933 evaluation board allows designers to evaluate the high performance AD5933 impedance converter with minimum effort. The evaluation board interfaces to the USB port possible to power the entire board from the ...
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AD5933 SCHEMATICS Figure 45. EVAL-AD5933EBZ USB Schematic Rev Page 05324-044 ...
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Figure 46. EVAL-AD5933EBZ Schematic Rev Page AD5933 05324-045 ...
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AD5933 Figure 47. Linear Regulator on the EVAL-AD5933EB Evaluation Board Rev Page 05324-046 ...
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Figure 48. Decoupling on the EVAL-AD5933EB Evaluation Board Rev Page AD5933 05324-047 ...
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... FEC 1170658 FEC 9341501 4 Not inserted 4 Not inserted FEC 9330402 FEC 9331662 FEC 9330810 FEC 9330399 FEC 9332383 FEC 9330771 FEC 8731128 FEC 1111349 Not Inserted FEC 9758070 Digi-Key 428-1669-ND ADR433ARZ ADP3303ARZ-3.3 AD5933YRSZ/AD5934YRSZ FEC 9509658 AEL-4313 FEC 651-813 FEC 522-764 Digi-Key 167-1011-ND ...
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... OUTLINE DIMENSIONS 2.00 MAX 0.05 MIN COPLANARITY 0.10 ORDERING GUIDE Model 1 Temperature Range AD5933YRSZ −40°C to +125°C AD5933YRSZ-REEL7 −40°C to +125°C EVAL-AD5933EBZ −40°C to +125° RoHS Compliant Part. 6.50 6.20 5. 5.60 5.30 8.20 5.00 7.80 7. 0.25 1.85 0.09 1 ...
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AD5933 NOTES refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors). ©2005–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05324-0-8/10(C) Rev ...