AD7738BRU Analog Devices Inc, AD7738BRU Datasheet
AD7738BRU
Specifications of AD7738BRU
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AD7738BRU Summary of contents
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FEATURES High Resolution ADC 24 Bits No Missing Codes 0.0015% Nonlinearity Optimized for Fast Channel Switching 18-Bits p-p Resolution (21 Bits Effective) at 500 Hz 16-Bits p-p Resolution (19 Bits Effective) at 8.5 kHz 15-Bits p-p Resolution (18 Bits ...
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AD7738–SPECIFICATIONS REFIN(+) = 2.5 V, REFIN(– AINCOM = 2.5 V, MUXOUT(+) = ADCIN(+), MUXOUT(–) = ADCIN(–), Internal Buffer ON, AIN Range = f = 6.144 MHz; unless otherwise noted.) MCLK Parameter ADC PERFORMANCE— CHOPPING ENABLED Conversion Time ...
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Parameter LOGIC INPUTS SCLK, DIN, CS, and RESET Inputs Input Current Input Current CS Input Capacitance T– – T– T– – T– ...
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AD7738 TIMING SPECIFICATIONS ( Parameter Min MASTER CLOCK RANGE 500 2 READ OPERATION ...
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CS SCLK DOUT CS SCLK DIN Figure 3. Load Circuit for Access Time and Bus Relinquish Time REV MSB Figure 1. Read Cycle Timing Diagram ...
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... P1 Voltage to AGND . . . . . . . . . . . . . . –0 Digital Input Voltage to DGND . . . . . –0 Digital Output Voltage to DGND . . . . –0 Model AD7738BRU CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD7738 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges ...
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Pin No. Mnemonic Description 1 SCLK Serial Clock. Schmitt-Triggered Logic Input. An external serial clock is applied to this input to transfer serial data to or from the AD7738. 2 MCLKIN Master Clock Signal for the ADC. This can be ...
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AD7738 Pin No. Mnemonic Pin Description 15 ADCIN(–) ADC Negative Input. In normal circuit configuration, this pin should be connected to the MUXOUT– pin. 16 ADCIN(+) ADC Positive Input. In normal circuit configuration, this pin should be connected to the ...
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OUTPUT NOISE AND RESOLUTION SPECIFICATION The AD7738 can be operated with chopping enabled or disabled, allowing the ADC to be programmed either to optimize the throughput rate and channel switching time or to optimize offset drift performance. Noise tables for ...
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AD7738 CHOPPING DISABLED The second mode, in which the AD7738 is configured with chopping disabled (CHOP = 0), provides faster conversion time while still maintaining high resolution. Tables show the –3 dB frequencies and typical performance versus ...
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CHOP = FILTER WORD TPC 1. No Missing Codes Performance, Chopping Enabled 25 24 CHOP = ...
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AD7738 Addr Dir Register hex Communications 00 W I/O Port 01 R/W Revision 02 R Test 03 R/W ADC Status 04 R Checksum 05 R/W ADC ZS Calibration 06 R/W ADC FS 07 R/W 1 Channel Data 08- ...
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REGISTER DESCRIPTION The AD7738 is configurable through a series of registers. Some of them configure and control general AD7738 features, others are specific to each channel. The register data widths vary from 8 bits to 24 bits. All registers are ...
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AD7738 I/O Port Register 8 Bits, Read/Write Register, Address 01h, Default Value 30h + Digital Input Value The bits in this register are used to configure and access the digital I/O pin on the AD7738. Bit Bit 7 Mnemonic P0 ...
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Checksum Register 16 Bits, Read/Write Register, Address 05h This register is described in the “AD7732/34/38 Checksum Register” Technical Note. ADC Zero Scale Calibration Register 24 Bits, Read/Write Register, Address 06h, Default Value 800000h The register holds the ADC Zero-Scale Calibration ...
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AD7738 Channel Status Registers 8 Bits, Read-Only Register, Address 20h–27h, Default Value 20h These registers contain individual channel status information and some general AD7738 status information. Reading the Status registers can be associated with reading the Data registers in the ...
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Channel Setup Registers 8 Bits, Read/Write Register, Address 28h–2Fh, Default Value 00h These registers are used to configure the selected channel, its input voltage range, and set up the corresponding Channel Status register. Bit Bit 7 Mnemonic BUF OFF Default ...
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AD7738 Mode Register 8 Bits Read/Write Register, Address 38h–3Fh, Default Value 00h The Mode register configures the part and determines the part’s operating mode. Writing to the Mode register will clear the ADC Status register, set the RDY pin to ...
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MD2 MD1 MD0 Operating Mode Idle Mode The default mode after Power-On or Reset. The AD7738 returns to this mode automatically after any calibration or after a single conversion Continuous Conversion Mode The AD7738 ...
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AD7738 DIGITAL INTERFACE DESCRIPTION Hardware The AD7738 serial interface can be connected to the host device via the serial interface in several different ways. The CS pin can be used to select the AD7738 as one of several circuits connected ...
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Single Conversion and Reading Data When the Mode register is being written, the ADC Status Byte is cleared and the RDY pin goes high regardless of its previous state. When the single conversion command is written to the Mode register, ...
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AD7738 Continuous Conversion Mode When the Mode register is being written, the ADC Status Byte is cleared and the RDY pin goes high regardless of its previous state. When the continuous conversion command is written to the Mode register, the ...
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CS SCLK DIN 38h 48h DOUT RDY WRITE WRITE CONVERSION COMM. MODE ON CH0 REGISTER REGISTER COMPLETE Figure 12. Continuous Conversion CH0 and CH1, Continuous Read Continuous Read (Continuous Conversion) Mode When the Continuous RD bit in the Mode register ...
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AD7738 MULTIPLEXER BUFFER MUXOUT ADCIN AIN(+) AIN(– ) CHOP f MCLK Figure 13. Channel Signal Chain Diagram with Chopping Enabled Multiplexer, Conversion, and Data Output Timing The specified “Conversion Time” includes one or two “Settling” and “Sampling” periods and a ...
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CHOP = 1 –20 –30 –40 –50 –60 0.1 1 NORMALIZED INPUT FREQUENCY (INPUT FREQUENCY CONVERSION TIME) a. Chopping Enabled Analog Inputs Voltage Range The absolute input voltage range with input the buffer enabled is restricted from AGND ...
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AD7738 Voltage Reference Inputs The AD7738’s reference inputs, REFIN(+) and REFIN(–), provide a differential reference input capability. The common- mode range for these differential inputs is from AGND to AV The nominal reference voltage for specified operation is 2.5 V. ...
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CALIBRATION The AD7738 provides zero-scale self-calibration, and zero and full system calibration capability, which can effectively reduce the offset error and gain error to the order of the noise. After each conversion, the ADC conversion result is scaled using the ...
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AD7738 28-Lead Thin Shrink Small Outline Package (TSSOP) PIN 1 0.15 0.05 COPLANARITY 0.10 OUTLINE DIMENSIONS (RU-28) Dimensions shown in millimeters 9.80 9.70 9. 4.50 4.40 4.30 6.40 BSC 1 14 0.65 1.20 BSC MAX 0.30 0.20 0.19 ...