AD7947 AD [Analog Devices], AD7947 Datasheet
AD7947
Related parts for AD7947
AD7947 Summary of contents
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... Reference derived from the power supply pipeline delay. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved. AD7940 SCLK SDATA CS 250 kSPS 500 kSPS AD7687 AD7688 AD7685 AD7686 AD7944 AD7947 AD7942 AD7946 www.analog.com ...
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AD7940 TABLE OF CONTENTS Specifications..................................................................................... 3 Timing Specifications....................................................................... 5 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Pin Configurations and Function Descriptions ........................... 7 Terminology ...................................................................................... 8 Typical Performance Characteristics ............................................. 9 Circuit Information ........................................................................ 11 Converter Operation.................................................................. 11 Analog Input ...
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SPECIFICATIONS 2.5 MHz SCLK Table 2. Parameter DYNAMIC PERFORMANCE 2 Signal-to-Noise + Distortion (SINAD) 2 Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) 2 Intermodulation Distortion ...
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AD7940 Parameter 4 Power Dissipation Normal Mode (Operational) Full Power-Down 1 Temperature range for B Version is –40°C to +85°C. 2 See the Terminology section. 3 Sample tested at initial release to ensure compliance. 4 See the Power vs. Throughput ...
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TIMING SPECIFICATIONS Sample tested at initial release to ensure compliance. All input signals are specified with (10 voltage level 5.5 V; ...
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AD7940 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 4. Parameter V to GND DD Analog Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND Input Current to Any Pin Except Supplies ...
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PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS SOT- AD7940 GND SDATA 2 5 TOP VIEW V SCLK (Not to Scale) Figure 3. SOT-23 Pin Configuration Table 5. Pin Function Descriptions Pin No. Pin No. ...
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AD7940 TERMINOLOGY Integral Nonlinearity This is the maximum deviation from a straight line passing through the endpoints of the ADC transfer function. The end- points of the transfer function are zero scale, a point 1/2 LSB below the first code ...
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TYPICAL PERFORMANCE CHARACTERISTICS Figure 5 shows a typical FFT plot for the AD7940 at 100 kSPS sample rate and 10 kHz input frequency. Figure 6 shows the signal-to-(noise + distortion) ratio performance versus the input frequency for various supply voltages ...
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AD7940 1 3.00V DD ° TEMP = 25 C 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 0 2000 4000 6000 8000 10000 12000 14000 16000 CODE Figure 9. AD7940 Typical INL 0 3.00V DD ° ...
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CIRCUIT INFORMATION The AD7940 is a fast, low power, 14-bit, single-supply ADC. The part can be operated from a 2. 5.5 V supply. When operated at either supply, the AD7940 is capable of ...
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AD7940 ADC TRANSFER FUNCTION The output coding of the AD7940 is straight binary. The de- signed code transitions occur at successive integer LSB values, i.e., 1 LSB, 2 LSBs. The LSB size is V /16384. The ideal transfer DD characteristic ...
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MODES OF OPERATION The mode of operation of the AD7940 is selected by controlling the (logic) state of the CS signal during a conversion. There are two possible modes of operation, normal and power-down. The point at which CS is ...
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AD7940 POWER-DOWN MODE This mode is intended for use in applications where slower throughput rates are required. Either the ADC is powered down between each conversion series of conversions may be performed at a high throughput rate, and ...
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POWER VS. THROUGHPUT RATE By using the power-down mode on the AD7940 when not converting, the average power consumption of the ADC decreases at lower throughput rates. Figure 19 shows how as the throughput rate is reduced, the part remains ...
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AD7940 SERIAL INTERFACE Figure 20 shows the detailed timing diagram for serial interfac- ing to the AD7940. The serial clock provides the conversion clock and also controls the transfer of information from the AD7940 during conversion. The CS signal initiates ...
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MICROPROCESSOR INTERFACING The serial interface on the AD7940 allows the part to be directly connected to a range of many different microprocessors. This section explains how to interface the AD7940 with some of the more common microcontroller and DSP serial ...
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AD7940 For example, if the ADSP-2189 had a 20 MHz crystal, such that it had a master clock frequency of 40 MHz, the master cycle time would be 25 ns. If the SCLKDIV register is loaded with the value 7, ...
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APPLICATION HINTS GROUNDING AND LAYOUT The printed circuit board that houses the AD7940 should be designed such that the analog and digital sections are separated and confined to certain areas of the board. This facilitates the use of ground planes ...
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AD7940 OUTLINE DIMENSIONS INDICATOR 0.15 MAX Figure 24. 6-Lead Small Outline Transistor Package [SOT-23] (RJ-6). Dimensions shown in millimeters. Figure 25. 8-Lead Micro Small Outline Package [MSOP] (RM-8). Dimensions shown in millimeters. ORDERING GUIDE Models Temperature Range AD7940BRJ-R2 −40°C to ...