AD7706BRU-REEL7 Analog Devices Inc, AD7706BRU-REEL7 Datasheet
AD7706BRU-REEL7
Specifications of AD7706BRU-REEL7
Related parts for AD7706BRU-REEL7
AD7706BRU-REEL7 Summary of contents
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FEATURES AD7705: 2 fully differential input channel ADCs AD7706: 3 pseudo differential input channel ADCs 16 bits no missing codes 0.003% nonlinearity Programmable gain front end: gains from 1 to 128 3-wire serial interface SPI®-, QSPI™-, MICROWIRE™-, and DSP-compatible Schmitt-trigger ...
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AD7705/AD7706 TABLE OF CONTENTS Features .............................................................................................. 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 3 Product Highlights ........................................................................... 4 Specifications..................................................................................... 5 Timing Characteristics ................................................................ 8 Absolute Maximum Ratings............................................................ 9 ESD Caution.................................................................................. 9 Pin Configurations and ...
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REVISION HISTORY 5/06—Rev Rev. C Updated Format.................................................................. Universal Changes to Table 1 ............................................................................3 Updated Outline Dimensions........................................................42 Changes to Ordering Guide...........................................................43 6/05—Rev Rev. B Updated Format.................................................................. Universal Changed Range of Absolute Voltage on Analog Inputs Universal Changes ...
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AD7705/AD7706 PRODUCT HIGHLIGHTS 1. The AD7705/AD7706 devices consume less than supplies and 1 MHz master clock, making them ideal for use in low power systems. Standby current is less than 8 μA. 2. The programmable ...
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SPECIFICATIONS REF IN(+) = 1.225 V with V DD otherwise noted. All specifications T MIN Table 1. Parameter STATIC PERFORMANCE No Missing Codes Output Noise 2 Integral Nonlinearity 3 Unipolar Offset Error Unipolar ...
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AD7705/AD7706 Parameter AIN Input Sampling Rate Reference Input Range REF IN(+) − REF IN(−) Voltage REF IN(+) − REF IN(−) Voltage REF IN Input Sampling Rate LOGIC INPUTS Input Current All Inputs, Except MCLK IN MCLK ...
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Parameter POWER REQUIREMENTS V Voltage DD 17 Power Supply Currents V Voltage DD 17 Power Supply Currents 18 Standby (Power-Down) Current 19, 20 Power Supply Rejection 1 Temperature range is −40°C to +85°C. 2 These numbers are established from characterization ...
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AD7705/AD7706 TIMING CHARACTERISTICS 5.25 V; GND = CLKIN 1, 2 Table 2. Timing Characteristics Limit MIN MAX Parameter (B Version 400 CLKIN 2.5 t ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameters V to GND DD Analog Input Voltage to GND Reference Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND Operating Temperature Range ...
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AD7705/AD7706 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS SCLK 1 MCLK IN 2 MCLK OUT 3 AD7705 CS 4 TOP VIEW (Not to Scale) RESET 5 AIN2(+) 6 AIN1(+) 7 AIN1(–) 8 Figure 3. AD7705 Pin Configuration Table 4. Pin Function Descriptions ...
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Mnemonic Pin No. AD7705 AD7706 Description 14 DIN DIN Serial Data Input. Serial data is written to the input shift register on the part. Data from the input shift register is transferred to the setup register, clock register, or communication ...
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AD7705/AD7706 OUTPUT NOISE (5 V OPERATION) Table 5 shows the AD7705/AD7706 output rms noise for the selectable notch and −3 dB frequencies for the parts, as selected by FS0 and FS1 of the clock register. The numbers given are for ...
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OUTPUT NOISE (3 V OPERATION) Table 7 shows the AD7705/AD7706 output rms noise for the selectable notch and −3 dB frequencies for the parts, as selected by FS0 and FS1 of the clock register. The numbers given are for the ...
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AD7705/AD7706 TYPICAL PERFORMANCE CHARACTERISTICS 32771 25° 2.5V RMS NOISE = 600nV REF 32770 GAIN = +128 50Hz UPDATE RATE 32769 32768 32767 32766 32765 32764 32763 0 100 200 300 400 ...
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TEK STOP: SINGLE SEQ 50.0kS OSCILLATOR = 4.9152MHz 2 OSCILLATOR = 2.4576MHz CH1 5.00V CH2 2.00V Figure 11. Crystal Oscillator Power-Up Time 5ms/DIV –40 –30 –20 –10 Figure 12. Standby ...
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AD7705/AD7706 ON-CHIP REGISTERS The AD7705/AD7706 each contain eight on-chip registers that can be accessed via the serial port. The first of these is a communication register that controls the channel selection, decides whether the next operation is a read or ...
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Table 11. Register Selection RS2 RS1 RS0 Table 12. Channel Selection for AD7705 CH1 CH0 AIN(+) ...
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AD7705/AD7706 Table 16. Operating Mode Options MD1 MD0 Operating Mode 0 0 Normal Mode. In this mode, the device performs normal conversions Self-Calibration. This activates self-calibration on the channel selected by CH1 and CH0 of the communication register. ...
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CLOCK REGISTER (RS2, RS1, RS0 = 0, 1, 0); POWER-ON/RESET STATUS: 05 HEXADECIMAL The clock register is an 8-bit register from which data can be read or to which data can be written. Table 18 outlines the bit designations for ...
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AD7705/AD7706 DATA REGISTER (RS2, RS1, RS0 = The data register is a 16-bit, read-only register that contains the most up-to-date conversion result from the AD7705/AD7706. If the communication register sets up the part for a write operation ...
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CIRCUIT DESCRIPTION The AD7705/AD7706 are Σ-Δ analog-to-digital converters (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. Each contains a Σ-Δ (or charge-balancing) ADC, a ...
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AD7705/AD7706 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 that the bipolar input ...
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On the AD7706, the voltages applied to the analog input channels are referenced to the COMMON input. For example, if AIN1(−) is 2.5 V and AD7705 is configured for unipolar operation with a gain of 2 and ...
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AD7705/AD7706 Filter Characteristics The AD7705/AD7706 digital filter is a low-pass filter with (sinx/x) response (also called sinc ). The transfer function for the filter is described in the z-domain by 3 − − ...
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ANALOG FILTERING The digital filter does not provide any rejection at integer multiples of the modulator sample frequency, as outlined earlier. However, due to the part’s high oversampling ratio, these bands occupy only a small fraction of the spectrum, and ...
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AD7705/AD7706 For a full system calibration, the zero-scale point must be presented to the converter first. It must be applied to the converter before the calibration step is initiated and remain stable until the step is complete. Once the zero-scale ...
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V /GAIN REF UPPER LIMIT ON AD7705 INPUT VOLTAGE AD7705/AD7706 INPUT RANGE GAIN CALIBRATIONS EXPAND (0.8 × V /GAIN TO REF OR CONTRACT THE 2.1 × V /GAIN) AD7705/AD7706 INPUT RANGE REF –0V DIFFERENTIAL OFFSET CALIBRATIONS MOVE INPUT ...
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AD7705/AD7706 THEORY OF OPERATION CLOCKING AND OSCILLATOR CIRCUIT The AD7705/AD7706 each require 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 ...
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The FSYNC input can also be used as a software start convert command, allowing the AD7705/AD7706 to be operated in a conventional converter fashion. In this mode, writing to the FSYNC bit starts conversion, and the falling edge of DRDY ...
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AD7705/AD7706 POWER SUPPLIES The AD7705/AD7706 operate with V DD 2.7 V and 5.25 V. Although the latch-up performance of the AD7705/AD7706 is good important that power is applied to the AD7705/AD7706 before signals are applied at the REF ...
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EVALUATING THE PERFORMANCE The recommended layout for the AD7705/AD7706 is outlined in their associated evaluations. Each evaluation board package includes a fully assembled and tested evaluation board, documentation, software for controlling the board over the printer port of a PC, ...
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AD7705/AD7706 DRDY SCLK t 5 DOUT SCLK t 12 DIN MSB Figure 19. Read Cycle Timing Diagram MSB Figure 20. Write Cycle ...
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CONFIGURING THE AD7705/AD7706 The AD7705/AD7706 contain six on-chip registers that the user can access via the serial interface. Communication with any of these registers is initiated by first writing to the communication register. Figure 21 outlines a flowchart of the ...
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AD7705/AD7706 MICROCOMPUTER/MICROPROCESSOR INTERFACING The flexible serial interface of the AD7705/AD7706 allows easy interfacing to most microcomputers and microprocessors. The flowchart in Figure 21 outlines the sequence to follow when interfacing a microcontroller or microprocessor to the AD7705/AD7706. Figure 22 through ...
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AD7705/AD7706-to-8051 Interface An interface circuit between the AD7705/AD7706 and the 8XC51 microcontroller is shown in Figure 23. The diagram shows the minimum number of interface connections with CS on the AD7705/AD7706 hardwired low. In the case of the 8XC51 interface, ...
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AD7705/AD7706 C Code for Interfacing AD7705 to 68HC11 #include <math.h> #include <io6811.h> #define NUM_SAMPLES 1000 /* change the number of data samples */ #define MAX_REG_LENGTH 2 /* this says that the max length of a register is 2 bytes */ ...
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SPCR = 0x3f; SPCR = 0x7f; /* clear the interrupt */ DDRD = 0x10; /* MOSI output, MISO input, SCK output */ while(PORTC & 0x10); /* wait for /DRDY to go low */ PORTC & 0xfb ; ...
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AD7705/AD7706 APPLICATIONS The AD7705 provides a dual-channel, low cost, high resolution analog-to-digital function. Because the analog-to-digital function is provided by a Σ-Δ architecture, the part is more immune to noisy environments, thus making it ideal for use in industrial and ...
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TEMPERATURE MEASUREMENT Another application of the AD7705 is temperature measure- ment. Figure 26 outlines a connection between a thermocouple and the AD7705. For this application, the AD7705 is operated in buffered mode to allow large decoupling capacitors on the front ...
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AD7705/AD7706 SMART TRANSMITTERS Another application where the low power, single-supply, 3-wire interface capabilities of the AD7705/AD7706 are beneficial is in smart transmitters. Figure 28 shows a block diagram of a smart transmitter using the AD7705. Because a smart transmitter must ...
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BATTERY MONITORING An application where the low power, single-supply operation is required is battery monitoring in portable equipment applications. Figure 29 shows a block diagram of a battery monitor using the AD7705 and an external multiplexer to measure differentially the ...
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AD7705/AD7706 OUTLINE DIMENSIONS 10.50 (0.4134) 10.10 (0.3976 7.60 (0.2992) 7.40 (0.2913) 10.65 (0.4193 10.00 (0.3937) 1.27 (0.0500) 2.65 (0.1043) BSC 2.35 (0.0925) 0.30 (0.0118) 0.10 (0.0039) 0.51 (0.0201) SEATING COPLANARITY PLANE 0.10 0.31 (0.0122) COMPLIANT TO ...
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... AD7706BRZ-REEL 1 −40°C to +85°C 1 AD7706BRZ-REEL7 −40°C to +85°C AD7706BRU −40°C to +85°C AD7706BRU-REEL −40°C to +85°C AD7706BRU-REEL7 −40°C to +85°C 1 AD7706BRUZ −40°C to +85°C 1 AD7706BRUZ-REEL −40°C to +85°C 1 AD7706BRUZ-REEL7 −40°C to +85°C ...
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AD7705/AD7706 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01166-0-5/06(C) Rev Page ...