AD7709BRUZ Analog Devices Inc, AD7709BRUZ Datasheet
AD7709BRUZ
Specifications of AD7709BRUZ
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AD7709BRUZ Summary of contents
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FEATURES 16-Bit - ADC Programmable Gain Front End Simultaneous 50 Hz and 60 Hz Rejection Update Rate VREF Select ™ Allows Absolute and Ratiometric Measurement Capability ISOURCE Select ™ 16-Bit No Missing Codes 13-Bit p-p Resolution ...
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AD7709 TABLE OF CONTENTS FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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SPECIFICATIONS DD 32.768 kHz Crystal; all specifications T Parameter ADC CHANNEL SPECIFICATION Output Update Rate ADC CHANNEL 2 No Missing Codes Resolution Output Noise and Update Rates 2 Integral Nonlinearity Offset Error Offset Error Drift vs. Temperature 3 ...
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AD7709 SPECIFICATIONS (continued) Parameter EXCITATION CURRENT SOURCES (IEXC1, IEXC2, and IEXC3) Output Current IEXC1, IEXC2 IEXC3 Initial Tolerance at 25∞C Drift Initial Current Matching at 25∞C (between IEXC1 and IEXC2) Drift Matching (between IEXC1 and IEXC2) Initial Current Matching at ...
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Parameter LOGIC OUTPUTS (Excluding XTAL2 Output High Voltage Output Low Voltage Output High Voltage Output Low Voltage OL Floating-State Leakage Current Floating-State Output Capacitance Data ...
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AD7709 TIMING CHARACTERISTICS Limit at T MIN Parameter (A, B Version) t 30.5176 Read Operation 100 ...
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SCLK t 12 DIN RDY SCLK t 5A DOUT REV (1.6mA WITH V SINK 100 A WITH V TO OUTPUT 1.6V PIN 50pF I (200 A WITH V SOURCE 100 ...
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AD7709 ABSOLUTE MAXIMUM RATINGS 25∞C, unless otherwise noted GND . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Pin No. Mnemonic Function 1 IOUT1 Output for Internal Excitation Current Source. Either current source IEXC1, IEXC2, IEXC3 combina- tion of the current sources, can be switched to this output. 2 IOUT2 Output for Internal Excitation Current Source. ...
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AD7709–Typical Performance Characteristics 32772 INPUT RANGE = 32771 UPDATE RATE = 19.79Hz 32770 32769 32768 32767 32766 32765 32764 0 100 200 300 400 500 600 READING NUMBER TPC 1. Typical Noise Plot on ± 20 ...
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ADC CIRCUIT INFORMATION Overview The AD7709 incorporates a - ADC channel with on-chip digital filtering intended for the measurement of wide dynamic range, low frequency signals such as those in weigh-scale, strain-gauge, pressure transducer, or temperature measurement applications. - ADC ...
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AD7709 As shown in the block diagram, the Sinc contain +V and –V , where V is the respective channel offset This offset is removed by performing a running average of 2, which means that the settling ...
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NOISE PERFORMANCE Tables II and III show the output rms noise and output peak-to- peak resolution in bits (rounded to the nearest 0.5 LSB) for a selection of output update rates. The numbers are typical and generated at a differential ...
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AD7709 Communications Register (A1 The Communications Register is an 8-bit write-only register. All communications to the part must start with a write operation to the Communications Register. The data written to the Communications Register determines whether ...
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Status Register (A1 Power-On-Reset = 00H) The ADC Status Register is an 8-bit read-only register. To access the ADC Status Register, the user must write to the Communica- tions Register, selecting the next operation to be ...
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AD7709 Configuration Register (A1 Power-On-Reset = 000007H) The Configuration Register is a 24-bit register from which data can either be read or to which data can be written. This register is used to select the input ...
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Table VII. Configuration Register Bit Designations (continued) Bit Bit Location Name Description CONFIG16 I1EN0 IEXC1 Current Source Enable Bit I1EN1 CONFIG15 P4DIG Digital Input Enable. Set by user to enable pin AIN4/ digital input. ...
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AD7709 Table VII. Configuration Register Bit Designations (continued) Bit Bit Location Name Description CONFIG3 UNI Unipolar/Bipolar Operation Selection Bit. Set by the user to enable unipolar operation. In this mode, the device uses straight binary output coding i.e., 0 differential ...
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CONFIGURING THE AD7709 The four user-accessible registers on the AD7709 are accessed via the serial interface. Communication with any of these registers is initiated by first writing to the Communications Register. The AD7709 begins converting on power-up without the need ...
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AD7709 DIGITAL INTERFACE As previously outlined, AD7709 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 this ...
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AD7709-to-68HC11 Interface Figure 11 shows an interface between the AD7709 and the 68HC11 microcontroller. The diagram shows the minimum (3-wire) interface with CS on the AD7709 hardwired low. In this scheme, the RDY bit of the Status Register is monitored ...
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AD7709 RDY output is connected to the IRQ2 input of the ADSP-2103/ ADSP-2105. The serial interface of the ADSP-2103/ADSP-2105 is set up for alternate framing mode. The RFS and TFS pins of the ADSP-2103/ADSP-2105 are configured as active low outputs ...
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Programmable Gain Amplifier The output from the buffer on the ADC is applied to the input of the on-chip programmable gain amplifier (PGA). The PGA can be programmed through eight different unipolar and bipolar ranges. The PGA gain range is ...
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AD7709 When the ADC is configured for bipolar operation, the coding is offset binary with a negative full-scale voltage resulting in a code of 000 . . . 000, a zero differential voltage resulting in a code of 100 . ...
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The printed circuit board that houses the AD7709 should be designed such that the analog and digital sections are separated and confined to certain areas of the board. A minimum etch technique is generally best for ground planes as it ...
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AD7709 A second key advantage to using the AD7709 in transducer-based applications is that the on-chip low-side power switch can be fully utilized in low power applications. The low-side power switch is connected in series with the cold side of ...
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Figure 21 shows a further enhancement to the circuit shown in Figure 20. Generally, dc excitation has been accepted as the normal method of exciting resistive based sensors like RTDs in temperature measurement applications. EMF1 IOUT1 IOUT2 RESISTIVE TRANSDUCER AIN1 ...
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AD7709 Smart Transmitters Smart transmitters are another key design-in area for the AD7709. The - converter, single-supply operation, 3-wire interface capabilities, and small package size are all of benefit in smart transmitters. Here, the entire smart transmitter must operate from ...
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Thin Shrink Small Outline Package [TSSOP] PIN 1 0.15 0.05 REV. A OUTLINE DIMENSIONS (RU-24) Dimensions shown in millimeters 7.90 7.80 7. 4.50 4.40 4.30 6.40 BSC 1 12 0.65 1.20 BSC MAX 8 0.30 0 0.20 ...
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AD7709 Revision History Location 3/03—Data Sheet changed from REV REV. A. Changes to SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . ...
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