EVAL-AD7942SDZ Analog Devices, EVAL-AD7942SDZ Datasheet
EVAL-AD7942SDZ
Specifications of EVAL-AD7942SDZ
Related parts for EVAL-AD7942SDZ
EVAL-AD7942SDZ Summary of contents
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... Rev. B Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. ...
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... Terminology .................................................................................... 12 Theory of Operation ...................................................................... 13 Circuit Information .................................................................... 13 Converter Operation .................................................................. 13 Typical Connection Diagram ................................................... 14 Digital Interface .......................................................................... 16 Application Hints ........................................................................... 23 Layout .......................................................................................... 23 Evaluating the Performance of AD7942 .................................. 23 Outline Dimensions ....................................................................... 24 Ordering Guide .......................................................................... 24 12/07—Rev Rev. A Changes to Table 1 ............................................................................. 1 Changes to General Description Section ....................................... 1 Changes to Table 6 ............................................................................. 7 Changes to Table 7 ............................................................................. 8 Changes to Circuit Information Section ..................................... 13 Changes to Table 9 ...
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SPECIFICATIONS VDD = 2 5.5 V, VIO = 2 VDD, V Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Absolute Input Voltage Analog Input CMRR Leakage Current Input Impedance ACCURACY No Missing Codes Differential Linearity Error ...
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... All specifications in decibels are referred to a full-scale input, FS. Tested with an input signal at 0.5 dB below full scale, unless otherwise specified. 4 With all digital inputs forced to VIO or GND as required. 5 During acquisition phase. 6 Contact Analog Devices, Inc., sales for an extended temperature range. Conditions I = +500 μA SINK I = − ...
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TIMING SPECIFICATIONS 1 VDD = 4 5 VIO = 2 5 VDD + 0.3 V, whichever is the lowest, unless otherwise stated, T Table 3. Parameter Conversion Time: CNV Rising Edge to ...
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AD7942 1 VDD = 2 4 VIO = 2 4 VDD + 0.3 V, whichever is the lowest, unless otherwise stated, T Table 4. Parameter Conversion Time: CNV Rising Edge to Data ...
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ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Rating Analog Inputs IN IN− 1 GND − 0 VDD + 0 ±130 mA REF GND − 0 VDD + 0.3 V Supply Voltages VDD and ...
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AD7942 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions 1 Pin No. Mnemonic Type Description 1 REF AI Reference Input Voltage. The V as closely as possible μF capacitor. 2 VDD P Power Supply. 3 ...
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TYPICAL PERFORMANCE CHARACTERISTICS 1.00 POSITIVE INL = +0.22LSB NEGATIVE INL = –0.34LSB 0.75 0.50 0.25 0 –0.25 –0.50 –0.75 –1.00 0 4096 8192 CODE Figure 5. Integral Nonlinearity vs. Code 150,000 129,941 100,000 50,000 0 0 915 0 1FFD 1FFE ...
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AD7942 86 SNR 85 SINAD 84 ENOB 83 82 2.0 2.5 3.0 3.5 4.0 REFERENCE VOLTAGE (V) Figure 11. SNR, SINAD, and ENOB vs. Reference Voltage 5V, –10dB REF REF ...
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VDD + VIO 250 0 –55 –35 – TEMPERATURE (°C) Figure 17. Power-Down Currents vs. Temperature 1000 900 800 VDD = 5V 700 600 VDD = 2.5V 500 400 300 200 100 VIO ...
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AD7942 TERMINOLOGY Linearity Error or 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 ...
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THEORY OF OPERATION IN+ REF GND IN– CIRCUIT INFORMATION The AD7942 is a fast, low power, single-supply, precise 14-bit ADC using successive approximation architecture. The AD7942 is capable of converting 250,000 samples per second (250 kSPS) and powers down between ...
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AD7942 REF (NOTE 3) NOTE 1: SEE THE VOLTAGE REFERENCE INPUT SECTION FOR REFERENCE SELECTION. NOTE USUALLY A 10µF CERAMIC CAPACITOR (X5R). REF NOTE 3: SEE DRIVER AMPLIFIER CHOICE SECTION. NOTE 4: OPTIONAL FILTER. ...
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FREQUENCY (kHz) Figure 25. Analog Input CMRR vs. Frequency During the acquisition phase, the impedance of the analog input, IN+, can be modeled as a parallel combination of the Capacitor C and ...
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AD7942 Power Supply The AD7942 is specified over a wide operating range from 2 5 has, unlike other low voltage converters, a noise low enough to design a low supply (2.5 V) 14-bit resolu- tion system ...
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CS Mode 3-Wire Without Busy Indicator This mode is most often used when a single AD7942 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 30 and the corresponding timing diagram is shown in Figure ...
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AD7942 CS Mode 3-Wire with Busy Indicator This mode is most often used when a single AD7942 is connected to an SPI-compatible digital host with an interrupt input. The connection diagram is shown in Figure 32 and the corresponding timing ...
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CS Mode 4-Wire Without Busy Indicator This mode is most often used when multiple AD7942s are connected to an SPI-compatible digital host. A connection diagram using two AD7942s is shown in Figure 34 and the corresponding timing diagram is given ...
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AD7942 CS Mode 4-Wire with Busy Indicator This mode is most often used when a single AD7942 is connected to an SPI-compatible digital host with an interrupt input and to keep CNV (which is used to sample the analog input) ...
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Chain Mode Without Busy Indicator This mode can be used to daisy-chain multiple AD7942s on a 3-wire serial interface. This feature is useful for reducing component count and wiring connections, for example, in isolated multiconverter applications or for systems with ...
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AD7942 Chain Mode with Busy Indicator This mode can also be used to daisy-chain multiple AD7942s on a 3-wire serial interface while providing a busy indicator. This feature is useful for reducing component count and wiring connections, for example, in ...
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... AD7942 (EVAL-AD7942CBZ). 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. Figure 42. Layout Example (Top Layer) Figure 43. Layout Example (Bottom Layer) Rev ...
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... This board can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRDx for evaluation/demonstration purposes. 3 This board allows control and communicate with all Analog Devices evaluation boards ending in the CB designator. ©2005–2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners ...