AD7707BR Analog Devices Inc, AD7707BR Datasheet
AD7707BR
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AD7707BR Summary of contents
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FEATURES Charge balancing ADC 16 bits, no missing codes ±0.003% nonlinearity High level (±10 V) and low level (±10 mV) input channels True bipolar ±100 mV capability on low level input Channels without requiring charge pumps Programmable gain front end ...
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AD7707 TABLE OF CONTENTS Features .............................................................................................. 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 3 Specifications ..................................................................................... 4 Timing Characteristics ................................................................ 8 Absolute Maximum Ratings ............................................................ 9 ESD Caution .................................................................................. 9 ...
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REVISION HISTORY 1/10—Rev Rev B Updated Format .................................................................. Universal Changes to Features Section ............................................................ 1 Changes to Table 1 ...................................................................................... 4 Changes to Table 5 ............................................................................ 9 Changes to Output Noise For Low Level Input Channels (3 V ...
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AD7707 SPECIFICATIONS REF IN(+) = 1.225 V with MCLK IN = 2.4576 MHz unless otherwise noted. All specifications T Table 1. Parameter STATIC PERFORMANCE Low Level Input Channels ...
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Parameter 2 Common-Mode 60 Hz Rejection Absolute/Common-Mode REF IN Voltage Absolute/Common-Mode AIN Voltage 2 AIN DC Input Current 2 AIN Sampling Capacitance 11, 12 AIN Differential Voltage Range AIN Input Sampling Rate Reference Input Range ...
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AD7707 Parameter MCLK IN Only V , Input Low Voltage INL V , Input High Voltage INH MCLK IN Only V , Input Low Voltage INL V , Input High Voltage INH LOGIC OUTPUTS (Including MCLK OUT Output ...
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Parameter 17 Normal Mode Power Dissipation 17 Normal Mode Power Dissipation 20 Standby (Power-Down) Current 1 Temperature range as follows: B Version, −40°C to +85°C. 2 These numbers are established from characterization or design at initial product release ...
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AD7707 TIMING CHARACTERISTICS 2 5.25 V, AGND = DGND = Table 4. Limit MIN MAX 1, 2 Parameter (B Version 400 CLKIN ...
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ABSOLUTE MAXIMUM RATINGS T = +25°C, unless otherwise noted. A Table 5. Parameter AV to AGND DGND AGND DGND DGND to AGND AIN1, AIN2 Input ...
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AD7707 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions Pin No. Mnemonic Description 1 SCLK Serial Clock, Schmitt-Triggered Logic Input. An external serial clock is applied to this input to access serial data from the AD7707. This serial ...
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Pin No. Mnemonic Description 18 DIN Serial Data Input with Serial Data Being Written to the Input Shift Register on the Part. Data from this input shift register is transferred to the setup register, clock register, or communications register, depending ...
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AD7707 TYPICAL PERFORMANCE CHARACTERISTICS 32,771 25° 2.5V RMS NOISE = 600nV REF 32,770 GAIN = 128 50Hz UPDATE RATE 32,769 32,768 32,767 32,766 32,765 32,764 32,763 0 100 200 300 400 ...
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TEK STOP: SINGLE SEQ 50.0kSPS OSCILLATOR = 4.9152MHz 2 OSCILLATOR = 2.4576MHz CH1 5.00V CH2 2.00V Figure 10. Typical Crystal Oscillator Power-Up Time 5ms/DIV –40 –30 –20 –10 Figure 11. ...
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AD7707 OUTPUT NOISE OUTPUT NOISE FOR LOW LEVEL INPUT CHANNELS (5 V OPERATION) Table 7 shows the AD7707 output rms noise and peak-to-peak resolution in unbuffered mode for the selectable notch and −3 dB frequencies for the part, as selected ...
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OUTPUT NOISE FOR LOW LEVEL INPUT CHANNELS (3 V OPERATION) Table 9 shows the AD7707 output rms noise and peak-to-peak resolution in unbuffered mode for the selectable notch and −3 dB frequencies for the part, as selected by FS0, FS1, ...
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AD7707 OUTPUT NOISE FOR HIGH LEVEL INPUT CHANNEL AIN3 (5 V OPERATION) Table 11 shows the AD7707 output rms noise and peak-to-peak resolution in unbuffered mode for the selectable notch and −3 dB frequencies for the part, as selected by ...
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OUTPUT NOISE FOR HIGH LEVEL INPUT CHANNEL AIN3 (3 V OPERATION) Table 13 shows the AD7707 output rms noise and peak-to-peak resolution for the selectable notch and −3 dB frequencies for the part, as selected by FS0, FS1, and FS2 ...
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AD7707 ON-CHIP REGISTERS The AD7707 contains eight on-chip registers that can be accessed via the serial port of the part. The first of these is a communications register that controls the channel selection, decides whether the next operation is a ...
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Table 16. Register Selection RS2 RS1 RS0 Table 17. Channel Selection for AD7707 CH1 CH0 AIN ...
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AD7707 Setup Register (RS2, RS1, RS0 = 0, 0, 1); Power-On/Reset Status: 0x01 The setup register is an eight-bit register from which data can either be read or to which data can be written. Table 18 outlines the bit designations ...
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Clock Register (RS2, RS1, RS0 = 0, 1, 0); Power-On/Reset Status: 0x05 The clock register is an 8-bit register from which data can either be read or to which data can be written. Table 22 outlines the bit designations for ...
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AD7707 Table 24. Output Update Rates 1 CLK FS2 FS1 ...
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CALIBRATION SEQUENCES The AD7707 contains a number of calibration options as previously outlined. Table 25 summarizes the calibration types, the operations involved, and the duration of the operations. There are two methods of determining the end of calibration. The first ...
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AD7707 CIRCUIT DESCRIPTION The AD7707 is a Σ-Δ ADC 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 Σ-Δ (or charge ...
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ANALOG INPUT ANALOG INPUT RANGES The AD7707 contains two low level pseudo differential analog input channels, AIN1 and AIN2. These input pairs provide programmable-gain, differential input channels that can handle either unipolar or pseudo bipolar input signals. It should be ...
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AD7707 In buffered mode, the analog inputs look into the high impedance inputs stage of the on-chip buffer amplifier. C this buffer amplifier such that source impedances do not affect the charging This buffer amplifier has an ...
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REFERENCE INPUT The AD7707 reference inputs, REF IN(+) and REF IN(−), provide a differential reference input capability. The common- mode range for these differential inputs is from GND to AV The nominal reference voltage, V REF IN(+) − REF IN(−), ...
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AD7707 DIGITAL FILTERING The AD7707 contains an on-chip low-pass digital filter that processes the output of the part’s Σ-Δ modulator. Therefore, the part not only provides the analog-to-digital conversion function but also provides a level of filtering. There are a ...
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POSTFILTERING The on-chip modulator provides samples at a 19.2 kHz output rate with f at 2.4576 MHz. The on-chip digital filter decimates CLKIN these samples to provide data at an output rate that corresponds to the programmed output rate of ...
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AD7707 CALIBRATION The AD7707 provides a number of calibration options that can be programmed via the MD1 and MD0 bits of the setup register. The different calibration options are outlined in the Setup Register (RS2, RS1, RS0 = 0, 0, ...
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MD0 bits in the setup register return This gives the earliest indication that the calibration sequence is complete. The DRDY line goes high when calibration is initiated and does not return low until there is a valid ...
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AD7707 POWER-UP AND CALIBRATION On power-up, the AD7707 performs an internal reset that sets the contents of the internal registers to a known state. There are default values loaded to all registers after power-on or reset. The default values contain ...
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USING THE AD7707 CLOCKING AND OSCILLATOR CIRCUIT The AD7707 requires a master clock input, which can be an external CMOS compatible clock signal applied to the MCLK IN pin with the MCLK OUT pin left unconnected. Alternatively, a crystal or ...
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AD7707 Because the FSYNC bit resets the digital filter, the full settling time of 3 × 1/output rate has to elapse before there is a new word loaded to the output register on the part. If the DRDY signal is ...
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POWER SUPPLIES The AD7707 operates with power supplies between 2.7 V and 5.25 V. There is no specific power supply sequence required for the AD7707, either the AV or the DV DD first. In normal operation, the DV must not ...
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AD7707 DIGITAL INTERFACE As previously outlined, the AD7707’s programmable functions are controlled using a set of on-chip registers. Data is written to these registers via the part’s serial interface and read access to the on-chip registers is also provided by ...
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CONFIGURING THE AD7707 The AD7707 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 communications register first. Figure 22 outlines a flow diagram of ...
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AD7707 START POWER-ON/RESET FOR AD7707 CONFIGURE AND INITIALIZE MICROCONVERTER/ MICROPROCESSOR SERIAL PORT WRITE TO COMMUNICATIONS REGISTER SELECTING CHANNEL AND SETTING UP NEXT OPERATION WRITE TO THE CLOCK REGISTER (20 HEX) WRITE TO CLOCK REGISTER SETTING THE CLOCK ...
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MICROCOMPUTER/MICROPROCESSOR INTERFACING The AD7707’s flexible serial interface allows for easy interface to most microcomputers and microprocessors. The flowchart of Figure 22 outlines the sequence that should be followed when interfacing a microcontroller or microprocessor to the AD7707. Figure 23 and ...
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AD7707 AD7707 TO 8XC51 INTERFACE An interface circuit between the AD7707 and the 8XC51 microcontroller is shown in Figure 24. The diagram shows the minimum number of interface connections with CS on the AD7707 hard-wired low. In the case of ...
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CODE FOR SETTING UP THE AD7707 The C Code for Interfacing AD7707 to 68HC11 section gives a set of read and write routines in C code for interfacing the 68HC11 microcontroller to the AD7707. The sample program sets up the ...
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AD7707 Writetoreg (int byteword); { int q; SPCR = 0x3f; SPCR = 0X7f; /* this sets the WiredOR mode (DWOM=1), Master mode (MSTR=1), SCK idles high (CPOL=1), /SS can be low always (CPHA=1), lowest clock speed (slowest speed which is ...
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APPLICATIONS INFORMATION The AD7707 provides a low cost, high resolution analog-to- digital function with two low level input channels and one high level input channel. Because the analog-to-digital function is provided by a Σ-Δ architecture, it makes the part more ...
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AD7707 AD420 DAC CONTROL ROOM AV DV REF IN(+) DD DD REF IN(–) AD7707 SENSORS RTD AIN1 mV MCLK IN THERMOCOUPLE AIN2 V AIN3 MCLK OUT AGND DGND +5V SMART VALVE/ACTUATOR AIN2 ACTUATOR/ VALVE AD7707 ±10V ...
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PRESSURE MEASUREMENT Other typical applications for the AD7707 include temperature and pressure measurement. Figure 28 shows the AD7707 used with a pressure transducer, the BP01 from Sensym. The pressure transducer is arranged in a bridge network and gives a differential ...
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AD7707 CHART RECORDERS Another area where both high and low level input channels are usually found is in chart recorder applications. Circular chart recorders generally have two requirements. The first utilizes the low level input channels of the AD7707 to ...
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OUTPUT NOISE FOR HIGH LEVEL INPUT CHANNEL, AIN3 5 V OPERATION Specified high level input voltage ranges of ±10 V, ± +10 V, and only utilize two gain different gain settings ...
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AD7707 3 V OPERATION Table 33 shows the AD7707 output rms noise and peak-to-peak resolution for the selectable notch and −3 dB frequencies for the part, as selected by FS0, FS1, and FS2 of the clock register. The numbers are ...
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OUTLINE DIMENSIONS 0.30 (0.0118) 0.10 (0.0039) COPLANARITY 0.10 COPLANARITY 13.00 (0.5118) 12.60 (0.4961 7.60 (0.2992) 7.40 (0.2913) 1 10.65 (0.4193) 10 10.00 (0.3937) 2.65 (0.1043) 2.35 (0.0925) SEATING 0.51 (0.0201) 1.27 0.33 (0.0130) PLANE (0.0500) 0.31 (0.0122) 0.20 ...
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... Supply DD AD7707BR 2 5.25 V AD7707BR-REEL 2 5.25 V AD7707BRZ 2 5.25 V AD7707BRZ-REEL 2 5.25 V AD7707BRZ-REEL7 2 5.25 V AD7707BRU 2 5.25 V AD7707BRU-REEL7 2 5.25 V AD7707BRUZ 2 5.25 V AD7707BRUZ-REEL 2 5.25 V AD7707BRUZ-REEL7 2 5. RoHS Compliant Part. Temperature Range Package Description −40°C to +85°C 20-Lead Standard Small Outline Package [SOIC_W] −40°C to +85°C 20-Lead Standard Small Outline Package [SOIC_W] − ...
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NOTES Rev Page AD7707 ...
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AD7707 NOTES ©2000–2010 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D08691-0-1/10(B) Rev Page ...