AD7641BSTZ Analog Devices Inc, AD7641BSTZ Datasheet
AD7641BSTZ
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AD7641BSTZ Summary of contents
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FEATURES Throughput 2 MSPS (wideband warp and warp mode) 1.5 MSPS (normal mode) INL: ±2 LSB typical, ±3 LSB max; ±8 ppm of full scale 18-bit resolution with no missing codes Dynamic range: 95.5 dB SNR: 93.5 dB typical @ ...
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AD7641 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications....................................................................... 5 Absolute Maximum Ratings............................................................ 7 ESD Caution.................................................................................. 7 Pin Configuration ...
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SPECIFICATIONS AVDD = DVDD = 2.5 V; OVDD = 2 3 Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Operating Input Voltage Analog Input CMRR Input Current 2 Input Impedance THROUGHPUT SPEED Complete Cycle Throughput Rate ...
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AD7641 Parameter Turn-On Settling Time REFBUFIN Output Voltage REFBUFIN Output Resistance EXTERNAL REFERENCE Voltage Range Current Drain REFERENCE BUFFER REFBUFIN Input Voltage Range REFBUFIN Input Current TEMPERATURE PIN Voltage Output Temperature Sensitivity Output Resistance DIGITAL INPUTS Logic Levels V IL ...
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TIMING SPECIFICATIONS AVDD = DVDD = 2.5 V; OVDD = 2 3 Table 3. Parameter CONVERSION AND RESET (Refer to Figure 29 and Figure 30) Convert Pulse Width Time Between Conversions (Warp Mode CNVST Low to ...
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AD7641 Table 4. Serial Clock Timings in Master Read After Convert Mode DIVSCLK[1] DIVSCLK[0] SYNC to SCLK First Edge Delay Minimum Internal SCLK Period Minimum Internal SCLK Period Maximum Internal SCLK High Minimum Internal SCLK Low Minimum SDOUT Valid Setup ...
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ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Analog Inputs/Outputs 1 IN+ , IN−, REF, REFBUFIN, TEMP, INGND, REFGND to AGND Ground Voltage Differences AGND, DGND, OGND Supply Voltages AVDD, DVDD OVDD AVDD to DVDD AVDD, DVDD to OVDD Digital Inputs 2 ...
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AD7641 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions Pin 1 No. Mnemonic Type Description AGND P Analog Power Ground Pin. 1, 36, 41 AVDD P Input Analog Power Pins. Nominally 2 ...
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Pin 1 No. Mnemonic Type Description 13 D6 DI/O When MODE[1: this output is used as Bit 6 of the parallel port data output bus. or EXT/INT When MODE[1: (serial mode), serial clock ...
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AD7641 Pin 1 No. Mnemonic Type Description 25 to D[14:17] DO Bit 14 to Bit 17 of the parallel port data output bus. These pins are always outputs, regardless of 28 the interface mode. 29 BUSY DO Busy Output. Transitions ...
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TERMINOLOGY Integral Nonlinearity Error (INL) Linearity error refers to the deviation of each individual code from a line drawn from negative full scale through positive full scale. The point used as negative full scale occurs ½ LSB before the first ...
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AD7641 TYPICAL PERFORMANCE CHARACTERISTICS 3.0 2.5 2.0 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 –2.5 –3.0 0 65536 131072 CODE Figure 5. Integral Nonlinearity vs. Code 40000 34844 35000 31003 30000 25000 20000 15000 10938 10000 4730 5000 683 ...
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FREQUENCY (kHz) Figure 11. FFT 20 kHz 95 93 ENOB SINAD ...
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AD7641 96.0 95.5 95.0 SNR 94.5 SINAD 94.0 93.5 93.0 –60 –50 –40 –30 INPUT LEVEL (dB) Figure 17. SNR and SINAD vs. Input Level (Referred to Full Scale –55 –35 ...
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APPPLICATIONS INFORMATION IN+ MSB 131,072C REF REFGND 131,072C 65,536C MSB IN– CIRCUIT INFORMATION The AD7641 is a very fast, low power, single-supply, precise 18-bit ADC using successive approximation architecture. The AD7641 features different modes to optimize performances according to the ...
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AD7641 TRANSFER FUNCTIONS Using the OB/ 2C digital input, except in 18-bit interface mode, the AD7641 offers two output codings: straight binary and twos complement. The LSB size with V = 2.048 × V REF 262,144, which ...
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TYPICAL CONNECTION DIAGRAM Figure 23 shows a typical connection diagram for the AD7641. Different circuitry shown in this diagram is optional and is discussed in the following sections. ANALOG INPUTS Figure 24 shows an equivalent circuit of the input structure ...
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AD7641 • The noise generated by the driver amplifier needs to be kept as low as possible to preserve the SNR and transition noise performance of the AD7641. The noise coming from the driver is filtered by the AD7641 analog ...
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However, because the AD7641 has a fine lead pitch, guarding this node is not practical. Therefore, in these industrial and other types of applications recommended to use a conformal coating, such as Dow Corning® 1-2577 or HumiSeal® 1B73. ...
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AD7641 POWER SUPPLY The AD7641 uses three sets of power supply pins: an analog 2.5 V supply AVDD, a digital 2.5 V core supply DVDD, and a digital input/output interface supply OVDD. The OVDD supply allows direct interface with any ...
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INTERFACES DIGITAL INTERFACE The AD7641 has a versatile digital interface that can be set up as either a serial or a parallel interface with the host system. The serial interface is multiplexed on the parallel data bus. The AD7641 digital ...
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AD7641 CNVST BUSY DATA PREVIOUS BUS CONVERSION Figure 33. Slave Parallel Data Timing for Reading (Read During Convert) 16-Bit and 8-Bit Interface (Master or Slave) In the ...
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EXT/INT = 0 CS CNVST BUSY t 29 SYNC SCLK t 15 SDOUT D17 Figure 35. Master Serial Data Timing for Reading (Read After Convert) EXT/INT = 0 ...
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AD7641 SLAVE SERIAL INTERFACE External Clock The AD7641 is configured to accept an externally supplied serial data clock on the SCLK pin when the EXT/ held high. In this mode, several methods can be used to read the data. The ...
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EXT/INT = 1 CS BUSY SCLK D17 D16 SDOUT SDIN X17 X16 t 33 Figure 38. Slave Serial Data Timing for Reading ...
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AD7641 MICROPROCESSOR INTERFACING The AD7641 is ideally suited for traditional dc measurement applications supporting a microprocessor, and ac signal processing applications interfacing to a digital signal processor. The AD7641 is designed to interface with a parallel 8-bit or 16-bit wide ...
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APPLICATION HINTS LAYOUT While the AD7641 has very good immunity to noise on the power supplies, exercise care with the grounding layout. To facilitate the use of ground planes that can be easily separated, design the printed circuit board that ...
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... AD7641BCPZ −40°C to +85°C 1 AD7641BCPZRL −40°C to +85°C 1 AD7641BSTZ −40°C to +85°C 1 AD7641BSTZRL −40°C to +85°C 2 EVAL-AD7641CB 3 EVAL-CONTROLBRD3 Pb-free part. 2 This board can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRD3 for evaluation/demonstration purposes. ...