AD7712ARZ Analog Devices Inc, AD7712ARZ Datasheet
AD7712ARZ
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AD7712ARZ Summary of contents
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FEATURES Charge Balancing ADC 24 Bits No Missing Codes 0.0015% Nonlinearity High Level and Low Level Analog Input Channels Programmable Gain for Both Inputs Gains from 1 to 128 Differential Input for Low Level Channel Low-Pass Filter with Programmable Filter ...
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AD7712–SPECIFICATIONS REF IN(–) = AGND; MCLK MHz unless otherwise stated. All specifications T Parameter STATIC PERFORMANCE No Missing Codes Output Noise Integral Nonlinearity @ 25° MIN MAX Positive Full-Scale Error 5 ...
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SPECIFICATIONS (continued) Parameter REFERENCE OUTPUT Output Voltage Initial Tolerance Drift Output Noise Line Regulation ( Load Regulation External Current 13 V INPUT BIAS Input Voltage Range V Rejection BIAS LOGIC INPUTS Input Current All Inputs except MCLK IN ...
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AD7712–SPECIFICATIONS Parameter POWER REQUIREMENTS Power Supply Voltages 18 AV Voltage Voltage DD AV – V Voltage DD SS Power Supply Currents AV Current DD DV Current DD V Current SS 20 Power Supply Rejection 21 Positive Supply ...
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TIMING CHARACTERISTICS Limit at T MIN Parameter (A, S Versions CLK IN 400 0.4 t CLK IN LO CLK IN t 0.4 t CLK IN HI CLK ...
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AD7712 TIMING CHARACTERISTICS Limit at T Parameter (A, S Versions) External Clocking Mode f f SCLK CLK CLK CLK IN ...
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Pin Mnemonic Function 1 SCLK Serial Clock. Logic input/output, depending on the status of the MODE pin. When MODE is high, the device is in its self-clocking mode, and the SCLK pin provides a serial clock output. This SCLK becomes ...
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AD7712 Pin Mnemonic Function DRDY Logic Output. A falling edge indicates that a new output word is available for transmission. The DRDY pin 21 will return high upon completion of transmission of a full output word. DRDY is also used ...
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Control Register (24 Bits) A write to the device with the A0 input low writes data to the control register. A read to the device with the A0 input low accesses the contents of the control register. The control register ...
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AD7712 PGA Gain Gain 128 Channel ...
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Tables I and II show the output rms noise for some typical notch and –3 dB frequencies. The numbers given are for the bipolar input ranges with 2.5 V. These numbers are REF typical and are generated ...
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AD7712 Figures 2a and 2b give information similar to that outlined in Table I. In these plots, the output rms noise is shown for the full range of available cutoffs frequencies rather than for some typical cutoff frequencies as in ...
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The AD7712 provides a number of calibration options that can be programmed via the on-chip control register. A calibration cycle can be initiated at any time by writing to this control regis- ter. The part can perform self-calibration using the ...
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AD7712 Input Sample Rate The modulator sample frequency for the device remains at f /512 (19.5 kHz @ MHz) regardless of the CLK IN CLK IN selected gain. However, gains greater than 1 are achieved by a ...
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Antialias Considerations The digital filter does not provide any rejection at integer mul- tiples of the modulator sample frequency ( This means that there are frequency bands, ± f wide (f ...
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AD7712 ANALOG INPUT FUNCTIONS Analog Input Ranges The analog inputs on the AD7712 provide the user with consid- erable flexibility in terms of analog input voltage ranges. One of the inputs is a differential, programmable gain, input channel that can ...
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V Input BIAS The V input determines at what voltage the internal analog BIAS circuitry is biased. It essentially provides the return path for analog currents flowing in the modulator, and as such it should be driven from a low ...
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AD7712 The AD7712 also provides the facility to write to the on-chip calibration registers, and, in this manner, the span and offset for the part can be adjusted by the user. The offset calibration regis- ter contains a value that ...
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Cal Type MD2, MD1, MD0 Self-Cal System Cal System Cal System Offset Cal Background Cal Span and Offset Limits Whenever a system calibration mode is ...
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AD7712 DIGITAL INTERFACE The AD7712’s serial communications port provides a flexible arrangement to allow easy interfacing to industry-standard microprocessors, microcontrollers, and digital signal processors. A serial read to the AD7712 can access data from the output register, the control register, ...
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Write Operation Data can be written to either the control register or calibration registers. In either case, the write operation is not affected by the DRDY line, and the write operation does not have any effect on the status of ...
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AD7712 Figure 13a shows a read operation from the AD7712 where RFS remains low for the duration of the data word transmis- sion. With DRDY low, the RFS input is brought low. The input SCLK signal should be low between ...
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Write Operation Data can be written to either the control register or calibration registers. In either case, the write operation is not affected by the DRDY line, and the write operation does not have any effect on the status of ...
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AD7712 SIMPLIFYING THE EXTERNAL CLOCKING MODE INTERFACE In many applications, the user may not require the facility of writing to the on-chip calibration registers. In this case, the serial interface to the AD7712 in external clocking mode can be simplified ...
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START CONFIGURE AND INITIALIZE C/ P SERIAL PORT BRING RFS, TFS AND A0 HIGH LOAD DATA FROM ADDRESS TO ACCUMULATOR REVERSE ORDER OF BITS BRING TFS AND A0 LOW WRITE DATA FROM ACCUMULATOR TO SERIAL BUFFER BRING TFS AND A0 ...
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AD7712 Table VIII. 8XC51 Code for Writing to the AD7712 MOV SCON,#00000000B; Configure 8051 for MODE 0 Operation & Enable Serial Reception MOV IE,#10010000B; Enable Transmit Interrupt MOV IP,#00010000B; Prioritize the Transmit Interrupt TFS SETB 91H; Bring RFS SETB 90H; ...
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APPLICATIONS 4–20 mA LOOP The AD7712’s high level input can be used to measure the current in 4–20 mA loop applications as shown in Figure 20. In this case, the system calibration capabilities of the AD7712 can be used to ...
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AD7712 0.005 (0.13) MIN PIN 1 0.200 (5.08) MAX 0.200 (5.08) 0.125 (3.18) 0.023 (0.58) 0.014 (0.36) CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN ...