EVAL-AD7291SDZ Analog Devices Inc, EVAL-AD7291SDZ Datasheet
EVAL-AD7291SDZ
Specifications of EVAL-AD7291SDZ
Related parts for EVAL-AD7291SDZ
EVAL-AD7291SDZ Summary of contents
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FEATURES 12-bit SAR ADC 8 single-ended analog input channels Analog input range 2.5 V 12-bit temperature-to-digital converter Temperature sensor accuracy of ±1°C typical Channel sequencer operation Specified for Logic ...
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AD7291 TABLE OF CONTENTS Features .............................................................................................. 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... Timing Specifications ............................................................ 5 Absolute Maximum Ratings ............................................................ 6 Thermal ...
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SPECIFICATIONS DRIVE unless otherwise noted. Table 2. Parameter DYNAMIC PERFORMANCE Signal-to-Noise Ratio (SNR) 2 Signal-to-Noise (+ Distortion) Ratio (SINAD) 2 Total Harmonic Distortion (THD) ...
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AD7291 Parameter LOGIC OUTPUTS Output High Voltage Output Low Voltage Floating State Leakage Current 3 Floating State Output Capacitance TEMPERATURE SENSOR—INTERNAL Operating Range Accuracy Resolution CONVERSION RATE Conversion Time 6 Autocycle Update Rate Throughput Rate POWER ...
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I C TIMING SPECIFICATIONS Guaranteed by initial characterization. All values were measured with the input filtering enabled. C bus line, with t and t measured between 0.3 × 2.5 V internal/external −40°C to +125°C, ...
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AD7291 ABSOLUTE MAXIMUM RATINGS Table 4. Parameter V to GND1, GND GND1, GND DRIVE Analog Input Voltage to GND1 Digital Input Voltage to GND1 Digital Output Voltage to GND1 V to GND1 REF GND to GND1 Input ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions Pin No. Mnemonic Description Analog Inputs. The AD7291 has eight single-ended analog inputs that are multiplexed into the on-chip track-and- IN3 IN4 18 ...
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AD7291 TYPICAL PERFORMANCE CHARACTERISTICS DRIVE f = 22.22ksps 400kHz –20 SCL f = 10kHz IN SNR = 71.209 THD = –81.66 –40 –60 –80 –100 –120 ...
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DRIVE 2.5 2.0 1.5 1.0 0 0.5 1.0 1.5 2.0 2.5 3.0 CURRENT LOAD (mA) Figure 10. V vs. Reference Output Drive REF ...
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AD7291 9 DRIVE 8 8.8 8.7 8.6 8.5 8.4 8.3 8.2 8.1 8 120 180 240 SCL FREQUENCY (kHz) Figure 16. Power vs. Throughput in Normal Mode 2.5 2.0 1.5 1.0 ...
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TERMINOLOGY Signal-to-Noise and Distortion Ratio (SINAD) The measured ratio of signal-to-noise and distortion at the output of the ADC. The signal is the rms amplitude of the fundamental. Noise is the sum of all nonfundamental signals up to half the ...
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AD7291 CIRCUIT INFORMATION The AD7291 includes an 8-channel multiplexer, an on-chip track-and-hold amplifier, an analog-to-digital converter (ADC), an on-chip oscillator, internal data registers, an internal tempera- 2 ture sensor, and an I C-compatible serial interface, all housed in a 20-lead ...
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ADC TRANSFER FUNCTION The output coding of the AD7291 is straight binary for the analog input channel conversion results and twos complement for the temperature conversion result. The designed code tran- sitions occur at successive LSB values (that is, 1 ...
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AD7291 Temperature Value Format One LSB of the ADC corresponds to 0.25°C. The temperature reading from the ADC is stored in a 12-bit twos complement format, to accommodate both positive and negative tempera- ture measurements. Sample temperature values are listed ...
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INTERNAL REGISTER STRUCTURE The AD7291 contains 34 internal registers (see Figure 23) that are used to store conversion results, high and low conversion limits, and information to configure and control the device. There are 33 data registers and one address ...
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AD7291 Table 9. AD7291 Register Addresses Hex Code 0x00 0x01 0x02 0x03 0x04 0x05 0 0 ...
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COMMAND REGISTER (0x00) The command register is a 16-bit write-only register that is used to set the operating modes of the AD7291. The bit functions are outlined in Table 10. A two-byte write is necessary when writing to the command ...
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AD7291 Table 12. Channel Selection Bits for Command Register D15 D14 D13 D12 D11 ...
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Table 17. T Conversion Result Register (First Read) SENSE MSB D15 D14 D13 D12 D11 ADD3 ADD2 ADD1 ADD0 B11 Table 18. T Result Register (Second Read) SENSE AVERAGE ...
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AD7291 HYSTERESIS REGISTER Each analog input channel and the internal temperature sensor has its own hysteresis register, which is a 16-bit read/write register. Only the 12 LSBs are used. Bit D15 to Bit D12 are not used in the register ...
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I C INTERFACE Control of the AD7291 is carried out via the I serial bus. The AD7291 is connected to this bus as a slave device under the control of a master device such as the processor. SERIAL BUS ...
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AD7291 WRITING TO THE AD7291 WRITING TWO BYTES OF DATA TO A 16-BIT REGISTER All registers on the AD7921 are 16-bit registers; therefore, two bytes of data are required to write a value to any one of these registers. Writing ...
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READING DATA FROM THE AD7291 READING TWO BYTES OF DATA FROM A 16-BIT REGISTER Reading the contents from any of the 16-bit registers is a 2-byte read operation. In this protocol, the first part of the transaction writes to the ...
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AD7291 MODES OF OPERATION When supplies are first applied to the AD7291, the ADC powers up in partial power-down mode and normally remains in this partial power-down state while not converting. Once the master addresses the AD7291, it exits partial ...
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The example in Figure 28 shows the command mode convert- ing on a sequence of channels including V 1. The master device asserts a start condition on SDA. 2. The master sends the 7-bit slave address followed by the write ...
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AD7291 AUTOCYCLE MODE The AD7291 can be configured to convert continuously on a programmable sequence of channels, making it the ideal mode of operation for system monitoring. This mode is useful for monitoring signals, such as battery voltage and temperature, ...
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... OUTLINE DIMENSIONS PIN 1 INDICATOR 0.80 0.75 0.70 SEATING PLANE ORDERING GUIDE 1 Model Temperature Range AD7291BCPZ −40°C to +125°C AD7291BCPZ-RL7 −40°C to +125°C EVAL-AD7291SDZ RoHS Compliant Part. 4.10 0.30 4.00 SQ 0.25 3.90 0.18 16 0.50 15 BSC EXPOSED PAD 11 10 0.50 TOP VIEW BOTTOM VIEW 0 ...
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AD7291 NOTES refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors). ©2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D08711-0-1/11(0) Rev ...