AD7715ANZ-3 Analog Devices Inc, AD7715ANZ-3 Datasheet
AD7715ANZ-3
Specifications of AD7715ANZ-3
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AD7715ANZ-3 Summary of contents
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FEATURES Charge-Balancing ADC 16 Bits No Missing Codes 0.0015% Nonlinearity Programmable Gain Front End Gains and 128 Differential Input Capability Three-Wire Serial Interface SPI™, QSPI™, MICROWIRE™ and DSP Compatible Ability to Buffer the Analog Input ...
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AD7715-5–SPECIFICATIONS f = 2.4576 MHz unless otherwise noted. All specifications T CLK IN Parameter STATIC PERFORMANCE No Missing Codes Output Noise Integral Nonlinearity Unipolar Offset Error 3 Unipolar Offset Drift Bipolar Zero Error 3 Bipolar Zero Drift 4 Positive Full-Scale ...
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AD7715-3–SPECIFICATIONS REF IN(–) = AGND 2.4576 MHz unless otherwise noted. All specifications T CLK IN Parameter STATIC PERFORMANCE No Missing Codes Output Noise Integral Nonlinearity Unipolar Offset Error 3 Unipolar Offset Drift Bipolar Zero Error 3 Bipolar Zero ...
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AD7715–SPECIFICATIONS (AD7715-5); REF IN(–) = AGND; MCLK MHz to 2.4576 MHz unless otherwise noted. All specifications T Pa rameter A Version SYSTEM CALIBRATION 14 Positive Full-Scale Calibration Limit (1.05 14 Negative Full-Scale Calibration Limit –(1.05 15 Offset ...
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TIMING CHARACTERISTICS Limit MIN Parameter (A Version 400 CLKIN 2.5 t 0.4 t CLK IN LO CLK IN t 0.4 t CLK IN HI CLK IN t 500 t 1 CLK IN t ...
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AD7715 ABSOLUTE MAXIMUM RATINGS +25 C unless otherwise noted AGND . . . . . . . . . . . . . . . . . . . . . . . . –0.3 ...
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Pin No. Mnemonic Function 1 SCLK Serial Clock. Logic Input. An external serial clock is applied to this input to access serial data from the AD7715. This serial clock can be a continuous clock with all data transmitted in a ...
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AD7715 TERMINOLOGY Integral Nonlinearity This is the maximum deviation of any code from a straight line passing through the endpoints of the transfer function. The end- points of the transfer function are Zero-Scale (not to be confused with Bipolar Zero), ...
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Communications Register (RS1, RS0 = 0, 0) The Communications Register is an eight-bit register from which data can either be read or to which data can be written. All com- munications to the part must start with a write operation ...
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AD7715 Setup Register (RS1, RS0 = 0, 1); Power On/Reset Status: 28 Hex The Setup Register is an eight-bit register from which data can either be read or to which data can be written. This register controls the setup which ...
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CLK* FS1 FS0 Output Update Rate 100 200 250 ...
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AD7715 OUTPUT NOISE AD7715-5 Table V shows the AD7715-5 output rms noise for the selectable notch and –3 dB frequencies for the part, as selected by FS1 and FS0 of the Setup Register. The numbers given are for the bipolar ...
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AD7715-3 Table IX shows the AD7715-3 output rms noise for the selectable notch and –3 dB frequencies for the part, as selected by FS1 and FS0 of the Setup Register. The numbers given are for the bipolar input ranges with ...
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AD7715 CALIBRATION SEQUENCES The AD7715 contains a number of calibration options as outlined previously. Table XIII summarizes the calibration types, the op- erations involved and the duration of the operations. There are two methods of determining the end of calibration. ...
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ANALOG +5V SUPPLY AD7715 AIN(+) DIFFERENTIAL ANALOG INPUT AIN(–) ANALOG AGND GROUND ANALOG +5V SUPPLY DIGITAL DGND GROUND REF IN(+) OUT 10 F 0.1 F AD780 MCLK IN GND REF IN(–) ...
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AD7715 with a gain of 2 and +2.5 V, the input voltage range REF on the AIN(+) input is +2 +3. AIN(–) is +2.5 V and the AD7715 is configured for bipolar mode ...
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Figure 4 shows the filter frequency response for a cutoff fre- quency of 15.72 Hz which corresponds to a first filter notch frequency of 60 Hz. The plot is shown from dc to 390 Hz. This response is repeated at ...
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AD7715 “full-scale” points. These points are derived by performing a conversion on the different input voltages provided to the input of the modulator during calibration result, the accuracy of the calibration can only be as good as the ...
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V /GAIN. This allows the input range above the REF nominal range. The in-built headroom in ...
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AD7715 The on-chip oscillator circuit also has a start-up time associated with it before it is oscillating at its correct frequency and correct voltage levels. The typical start-up time for the circuit with ...
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Measurement errors due to offset drift or gain drift can be elimi- nated at any time by recalibrating the converter. Using the sys- tem calibration mode can also minimize offset and gain errors in the signal conditioning circuitry. Integral and ...
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AD7715 package allows the user to evaluate the true performance of the part, independent of the analog input signal. The scheme involves using a test mode on the part where the differential inputs to the AD7715 are internally shorted together ...
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This state returns the interface to where the AD7715 is expecting a write operation to its Com- munications Register. ...
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AD7715 MICROCOMPUTER/MICROPROCESSOR INTERFACING The AD7715’s flexible serial interface allows for easy interface to most microcomputers and microprocessors. The flowchart of Figure 8 outlines the sequence which should be followed when interfacing a microcontroller or microprocessor to the AD7715. Figures 9, ...
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AD7715 to 8XC51 Interface An interface circuit between the AD7715 and the 8XC51 microcontroller is shown in Figure 10. The diagram shows the minimum number of interface connections with CS on the AD7715 hardwired low. In the case of the ...
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AD7715 Table XVI. C Code for Interfacing AD7715 to 68HC11 /* This program has read and write routines for the 68HC11 to interface to the AD7715 and the sample program sets the various registers and then reads 1000 samples from ...
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APPLICATIONS The AD7715 provides a low cost, high resolution analog-to- digital function. Because the analog-to-digital function is pro- vided by a sigma-delta architecture, it makes the part more immune to noisy environments thus making the part ideal for use in ...
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AD7715 Temperature Measurement Another application area for the AD7715 is in temperature measurement. Figure 13 outlines a connection from a thermo- couple to the AD7715. In this application, the AD7715 is oper- ated in its buffered mode to allow large ...
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Smart Transmitters Another area where the low power, single supply, three-wire interface capabilities is of benefit is in smart transmitters. Here, the entire smart transmitter must operate from the loop. Tolerances in the loop mean ...
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AD7715 PAGE INDEX Topic FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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REV. C OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 16-Lead Plastic DIP (N-16) 0.840 (21.33) 0.745 (18.93 0.280 (7.11) 0.240 (6.10 PIN 1 0.060 (1.52) ...