ad5933 Analog Devices, Inc., ad5933 Datasheet
ad5933
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ad5933 Summary of contents
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... Biomedical and Automotive Sensors Proximity Sensors FFT Processing GENERAL DESCRIPTION The AD5933 is a high precision impedance converter system solution which combines an on board frequency generator with a 12 Bit 1MSPS ADC. The frequency generator allows an external complex impedance to be excited with a known frequency ...
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... RESET .......................................................................................... 14 System Clock............................................................................... 14 Output Voltage............................................................................ 14 Post Gain ..................................................................................... 14 Performing a Frequency Sweep – Flow Chart ............................ 15 Serial Bus Interface..................................................................... 15 2 General I C Timing.................................................................... 15 Writing/Reading to the AD5933 .............................................. 16 Block Write.................................................................................. 17 AD5933 Read Operations ......................................................... 17 Error Correction......................................................................... 18 P.E.C. ............................................................................................ 18 Checksum.................................................................................... 18 User Command Codes .............................................................. 18 Outline Dimensions ....................................................................... 20 ESD Caution................................................................................ 20 Rev. PrA | Page ...
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... Pk-Pk Unipolar Voltage on Output. Voltage Error on Pk-Pk Output. DC bias of AC Signal Tolerance of DC Bias Pk-Pk Unipolar Voltage on Output. Voltage Error on Pk-Pk Output. DC bias of AC Signal Tolerance of DC Bias Pk-Pk Unipolar Voltage on Output. Voltage Error on Pk-Pk Output. DC bias of AC Signal Tolerance of DC Bias At 3 Volts Volts. AD5933 ...
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... AD5933 Parameter Min Narrowband Clock Feedthrough System Response Stage Analog Input VIN Input Leakage Current Input Capacitance Input Impedance ADC Accuracy Resolution Sampling Rate Integral Nonlinearity Differential Nonlinearity Offset Error Gain Error TEMPERATURE SENSOR Accuracy Resolution Temperature Conversion Time LOGIC INPUTS ...
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... SCL and SDA when transmitting F pF max Capacitive load for each bus line REPEATED CONDITION 2 Figure Interface Timing Diagram Rev. PrA | Page STOP START CONDITION AD5933 ...
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... AD5933 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 3. Mnemonic Function N/C No Connect. RFB_PIN External Feedback Resistor. This is used to set the gain of the input signal of the VIN node. VOUT Output AC Excitation signal. Programmble Frequnency range 0-50KHz. VIN Input Signal to transimpedance amplifier. External Feedback resistor will control gain of transimpedance amplifier. ...
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... PLL. The PLL has a gain stage of 520 and typically needs a reference clock of 32KHz on the MCLK pin. OUTPUT STAGE The output stage of the AD5933, shown in diagram below, provides a constant output frequency or frequency sweep function which has a programmable output voltage of 2/1/0.5/0.2V. The frequency sweep sequence is pre-progammed through the I2C interface ...
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... TF1 R VDD/2 Figure 5. ADC OPERATION The AD5933 has an integrated on board 12 bit ADC. The ADC contains an on-chip track and hold amplifier, a successive approximation A/D converter. Clocking for the A/D is provided using a divided down ratio of the reference clock. The A successive approximation analog to digital converter, based on a Capacitive DAC design Architecture. The figures below show simplified schematics of the ADC ...
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... Positive Temperature = ADC Code(d)/32 Negative Temperature = (ADC Code*(d) – 16384)/32 *Using all 14 bits of the data byte, includes the sign bit. Negative Temperature = (ADC Code(d)* – 8192)/32 *DB13 (sign bit) is removed from the ADC code AD5933 ...
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... AD5933 01, 0010, 1100, 0000 75°C 00, 1001, 0110, 0000 00, 0000, 0000, 0001 –0.03125°C 11, 1111, 1111, 1111 TEMPERATURE (°C) –40°C –30°C 11, 1100, 0100, 0000 11, 1011, 0000, 0000 Figure 9. Temperature to Digital Transfer Function Preliminary Technical Data 150°C Rev. PrA | Page ...
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... D7-D0 8Ah D15-D8 8Bh D7-D0 8Ch D7-D0 8Dh D7-D0 8Eh D7-D0 8fh D7-D0 90h D15-D8 91h D7-D0 92h D15-D8 93h D7-D0 Rev. PrA | Page AD5933 Read/Write Register Register Type Read/Write RAM Read/Write RAM Read/Write RAM Read/Write RAM Read/Write RAM Read/Write RAM Read/Write RAM Read/Write RAM Read/Write RAM Read/Write ...
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... AD5933 Register Name Real Data Imaginary Data Checksum Reg Add. Register Data [8Bits] 94h D15-D8 95h D7-D0 96h D15-D8 97h D7-D0 98h D7-D0 Rev. PrA | Page Preliminary Technical Data Read/Write Register Register Type Read Only RAM Read Only RAM Read Only RAM Read Only ...
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... Preliminary Technical Data CONTROL REGISTER The AD5933 contains a 16 bit control register (address 80h and 81h) that set the AD5933 control modes. The five MSB’s of the control register are decoded to provide control functions for frequency sweep, power down and various other control functions, defined in Table below ...
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... AD5933 CONTROL REGISTER DECODE: INITIALIZE SENSOR WITH START FREQUENCY This command enables the DDS to output the start frequency for an indefinite time used is to excite the sensor initially. When the output load (sensor) has settled after a time determined by the user, the user must initiate a “start frequency sweep” ...
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... RESET SERIAL BUS INTERFACE Control of the AD5933 is carried out via the 1 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 serial bus slave address. When the device is powered up, it will do so with a default serial bus address ...
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... STOP condition. WRITING/READING TO THE AD5933 The interface specification defines several different protocols for different types of read and write operations. The ones used in the AD5933 are discussed below. The following abbreviations are used Start ...
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... In this operation, the master device writes a block of data to a slave device. The start address for a block write must previously have been set. In the case of the AD5933 this is done by setting a pointer to set the RAM/OTP address. 1. The master device asserts a start condition on SDA. ...
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... Correction) byte after all commands. This enables the user to verify that the data received by or sent from the AD5933 is correct. The PEC byte is an optional byte sent after that last data byte has been written to or read from the AD5933. The protocol is as follows: 1. ...
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... This command is used when reading multiple bytes from the RAM/Memory. See block write section for further explanations. This command enables the user to set the address pointer to any location in the memory. The data will contain the address register of the register the pointer should be pointing to. Rev. PrA | Page AD5933 ...
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... AD5933 OUTLINE DIMENSIONS ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges ...