EVAL-AD7705EB Analog Devices Inc, EVAL-AD7705EB Datasheet
EVAL-AD7705EB
Specifications of EVAL-AD7705EB
Related parts for EVAL-AD7705EB
EVAL-AD7705EB Summary of contents
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FEATURES AD7705: Two Fully Differential Input Channel ADCs AD7706: Three Pseudo Differential Input Channel ADCs 16 Bits No Missing Codes 0.003% Nonlinearity Programmable Gain Front End Gains from 1 to 128 Three-Wire Serial Interface SPI™, QSPI™, MICROWIRE™ and DSP ...
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AD7705/AD7706–SPECIFICATIONS with REF IN(–) = GND; MCLK IN = 2.4576 MHz unless otherwise noted. All specifications T DD Parameter STATIC PERFORMANCE No Missing Codes Output Noise 2 Integral Nonlinearity Unipolar Offset Error 4 Unipolar Offset Drift ...
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Parameter LOGIC OUTPUTS (Including MCLK OUT Output Low Voltage Output Low Voltage Output High Voltage Output High Voltage OH Floating State Leakage Current 13 Floating State Output Capacitance Data ...
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AD7705/AD7706 TIMING CHARACTERISTICS Limit MIN Parameter (B Version 400 CLKIN 2.5 t 0.4 t CLKIN LO CLKIN t 0.4 t CLKIN HI CLKIN t 500 t 1 CLKIN t 100 2 Read Operation ...
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... Thermal Impedance . . . . . . . . . . . . . . . . . . . . 105 C/W JA Lead Temperature, (Soldering, 10 sec +260 Model Supply AD7705BN 2 5.25 V AD7705BR 2 5.25 V AD7705BRU 2 5.25 V EVAL-AD7705EB AD7706BN 2 5.25 V AD7706BR 2 5.25 V AD7706BRU 2 5.25 V EVAL-AD7706EB REV. A SOIC Package, Power Dissipation . . . . . . . . . . . . . . . 450 mW Thermal Impedance . . . . . . . . . . . . . . . . . . . . . 75 C/W JA Lead Temperature, Soldering Vapor Phase (60 sec +215 ...
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AD7705/AD7706 SCLK 1 MCLK IN 2 MCLK OUT 3 AD7705 CS 4 TOP VIEW 5 RESET (Not to Scale) AIN2(+) 6 AIN1(+) 7 AIN1(–) 8 Pin No. Mnemonic 1 SCLK 2 MCLK IN 3 MCLK OUT CS 4 RESET 5 ...
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Pin No. Mnemonic 10 REF IN(–) 11 AIN2(–)[AIN3] DRDY 12 13 DOUT 14 DIN GND OUTPUT NOISE (5 V OPERATION) Table I shows the AD7705/AD7706 output rms noise for the selectable notch and –3 dB frequencies ...
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AD7705/AD7706 Table II. Peak-to-Peak Resolution vs. Gain and Output Update Rate @ 5 V Filter First Notch and O/P –3 dB Gain of Data Rate Frequency 1 MCLK IN = 2.4576 MHz 15.72 ...
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+ 2.5V RMS NOISE = 600nV REF 32770 GAIN = 128 50Hz UPDATE RATE 32769 32768 32767 32766 32765 32764 32763 0 100 200 300 400 500 600 READING ...
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AD7705/AD7706 TEK STOP: SINGLE SEQ 50.0kS OSCILLATOR = 4.9152 MHz 2 OSCILLATOR = 2.4576 MHz CH1 5.00V CH2 2.00V Figure 8. Typical Crystal Oscillator Power-Up Time ON-CHIP REGISTERS The AD7705/AD7706 contains eight on-chip registers which can ...
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... Logic 0, the part looks at the AIN1(–) input internally shorted to itself on the AD7705 or at COMMON internally shorted to itself on the AD7706. This can be used as a test method to evaluate the noise performance of the part with no external noise sources. In this mode, the AIN1(–)/COMMON input should be connected to an external voltage within the allowable common-mode range for the part ...
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AD7705/AD7706 Setup Register (RS2, RS1, RS0 = 0, 0, 1); Power-On/Reset Status: 01 Hex The Setup Register is an eight bit register from which data can either be read or to which data can be written. Table IX outlines the ...
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Clock Register (RS2, RS1, RS0 = 0, 1, 0); Power-On/Reset Status: 05 Hex The Clock Register is an 8-bit register from which data can either be read or to which data can be written. Table XI outlines the bit designations ...
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AD7705/AD7706 Data Register (RS2, RS1, RS0 = The Data Register on the part is a 16-bit read-only register that contains the most up-to-date conversion result from the AD7705/ AD7706. If the Communications Register sets up the part ...
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CIRCUIT DESCRIPTION The AD7705/AD7706 is a sigma-delta A/D converter with on- chip digital filtering, intended for the measurement of wide dynamic range, low frequency signals such as those in industrial control or process control applications. It contains a sigma-delta (or ...
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AD7705/AD7706 ANALOG INPUT Analog Input Ranges The AD7705 contains two differential analog input pairs AIN1(+), AIN1(–) and AIN2(+), AIN2(–). These input pairs provide programmable-gain, differential input channels that can handle either unipolar or bipolar input signals. It should be noted ...
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Bipolar or unipolar options are chosen by programming the B/U bit of the Setup Register. This programs the channel for either unipolar or bipolar operation. Programming the channel for either unipolar or bipolar operation does not change any of the ...
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AD7705/AD7706 The cutoff frequency of the digital filter is determined by the value loaded to bits FS0 to FS1 in the CLOCK Register. Pro- gramming a different cutoff frequency via FS0 and FS1 does not alter the profile of the ...
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Self-Calibration A self-calibration is initiated on the AD7705/AD7706 by writing the appropriate values ( the MD1 and MD0 bits of the Setup Register. In the self-calibration mode with a unipo- lar input range, the zero scale point used ...
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AD7705/AD7706 range and the top of its input range) has to take into account the limitation on the positive full-scale voltage. The amount of offset which can be accommodated depends on whether the unipolar or bipolar mode is being used. ...
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When operating with a clock frequency of 2.4576 MHz, there difference in the current between an externally applied clock and a crystal resonator when operating with With and f ...
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AD7705/AD7706 Placing the part in standby mode reduces the total current typical with and 4 A with V DD part is operated from an external master clock provided this master clock is stopped. ...
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... PC. Noise levels in the signals applied to the AD7705/AD7706 may also affect performance of the part. The AD7705/AD7706 soft- ware evaluation package allows the user to evaluate the true REV. A performance of the part, independent of the analog input signal. The scheme involves using a test mode on the part where the inputs to the AD7705 are internally shorted together to provide a zero differential voltage for the analog modulator ...
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AD7705/AD7706 Figures 16 and 17 show timing diagrams for interfacing to the AD7705/AD7706 with CS used to decode the part. Figure 16 is for a read operation from the AD7705/AD7706’s output shift register while Figure 17 shows a write operation ...
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CONFIGURING THE AD7705/AD7706 The AD7705/AD7706 contains six on-chip registers that the user can accesses via the serial interface. Communication with any of these registers is initiated by writing to the Communica- tions Register first. Figure 18 outlines a flow diagram ...
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AD7705/AD7706 MICROCOMPUTER/MICROPROCESSOR INTERFACING The AD7705/AD7706’s flexible serial interface allows for easy interface to most microcomputers and microprocessors. The flowchart of Figure 10 outlines the sequence that should be followed when interfacing a microcontroller or microprocessor to the AD7705/AD7706. Figures 19, ...
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DRDY output line from the AD7705/AD7706. The monitoring of the DRDY line can be done in two ways. First, DRDY can be connected to one of the 8XC51’s port bits (such as ...
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AD7705/AD7706 Table XVII. C Code for Interfacing AD7705 to 68HC11 /* This program has read and write routines for the 68HC11 to interface to the AD7705 and the sample program sets the various registers and then reads 1000 samples from ...
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APPLICATIONS The AD7705 provides a dual channel, low cost, high resolution analog-to-digital function. Because the analog-to-digital func- tion is provided by a sigma-delta architecture, it makes the part more immune to noisy environments thus making the part ideal for use ...
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AD7705/AD7706 + 400 A REF IN(+) 6.25k REF IN(– AD7705 R AIN1(+) L2 RTD R AIN1(– GND CS DOUT DIN Figure 24. RTD Measurement Using the AD7705 ISOLATED SUPPLY V REF IN DD ...
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Battery Monitoring Another area where the low power, single supply operation is a requirement is battery monitoring in portable equipment appli- cations. Figure 26 shows a block diagram of a battery monitor that includes the AD7705 and an external multiplexer ...
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AD7705/AD7706 0.210 (5.33) 0.160 (4.06) 0.115 (2.93) 0.0118 (0.30) 0.0040 (0.10) OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 16-Pin Plastic DIP (N-16) 0.840 (21.34) 0.745 (18.92 0.280 (7.11) 0.240 (6.10 PIN 1 0.060 (1.52) 0.015 ...