Datasheet AD7641 (Analog Devices)

18-Bit, 2 MSPS SAR ADC AD7641 FEATURES FUNCTIONAL BLOCK DIAGRAM Throughput TEMP REFBUFIN REF REFGND DVDD DGND 2 MSPS (wideband warp and warp mode) AGND 1.5 MSPS (normal mode) AD7641 OVDD AVDD INL: ±2 LSB typical, ±3 LSB max; ±8 ppm of full scale OGND REF 18-bit resolution with no missing codes REF AMP SERIAL Dynamic range: 95.5 dB PORT IN+ 18 SWITCHED D[17:0] SNR: 93.5 dB typical @ 20 kHz (VREF = 2.5 V) IN– CAP DAC MODE0 PARALLEL THD: −112 dB typical @ 20 kHz (VREF = 2.5 V) INTERFACE MODE1 2.048 V internal reference: typ drift 10 ppm/°C; TEMP output PDREF CLOCK BUSY Differential input range: ±VREF (VREF up to 2.5 V) PDBUF RD CONTROL LOGIC AND No pipeline delay (SAR architecture) PD CALIBRATION CIRCUITRY CS Parallel (18-, 16-, or 8-bit bus) and RESET D0/OB/2C serial 5 V/3.3 V/2.5 V interface
001
SPI®/QSPI™/MICROWIRE™/DSP compatible WARP NORMAL CNVST
4761- 0
Single 2.5 V supply operation
Figure 1.
Power dissipation Table 1. PulSAR® Selection 75 mW typical @ 2 MSPS with internal REF 100 to 500 to 650 to 2 μW in power-down mode Type/kSPS 250 570 1000 >1000 Pb-free, 48-lead LQFP and 48-lead LFCSP_VQ
Pseudo AD7651, AD7650, AD7653,
Speed upgrade of the AD7674 , AD7678, AD7679
Differential AD7660, AD7652, AD7667

AD7661 AD7664, AD7666
APPLICATIONS
True Bipolar AD7610, AD7665 AD7612,
Medical instruments
AD7663 AD7671
High speed data acquisition/high dynamic data acquisition
True AD7675 AD7676 AD7677 AD7621,
Digital signal processing
Differential AD7622,
Spectrum analysis
AD7623
Instrumentation
18-Bit AD7631, AD7679 AD7634, AD7641, Multichannel/ AD7678 AD7674 AD7643
Communications
Simultaneous AD7654 AD7655
ATE GENERAL DESCRIPTION PRODUCT HIGHLIGHTS
1.
Fast Throughput.
The AD7641 is an 18-bit, 2 MSPS, charge redistribution SAR, The AD7641 is a 2 MSPS, charge redistribution, fully differential, analog-to-digital converter (ADC) that 18-bit SAR ADC. operates from a single 2.5 V power supply. The part contains a 2. high speed, 18-bit sampling ADC, an internal conversion clock,
Superior Linearity.
an internal reference (and buffer), error correction circuits, and The AD7641 has no missing 18-bit code. both serial and parallel system interface ports. It features two 3.
Internal Reference.
very high sampling rate modes (wideband warp and warp) and The AD7641 has a 2.048 V internal reference with a typical a fast mode (normal) for asynchronous rate applications. The drift of ±10 ppm/°C and an on-chip TEMP sensor. AD7641 is hardware factory calibrated and tested to ensure ac 4.
Single-Supply Operation.
parameters, such as signal-to-noise ratio (SNR), in addition to The AD7641 operates from a 2.5 V single supply. the more traditional dc parameters of gain, offset, and linearity. 5.
Serial or Parallel Interface.
The AD7641 is available in Pb-free only packages with Versatile parallel (16- or 8-bit bus) or 2-wire serial interface operation specified from −40°C to +85°C. arrangement compatible with 2.5 V, 3.3 V, or 5 V logic.
Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 www.analog.com Trademarks and registered trademarks are the property of their respective owners. Fax: 781.461.3113 ©2006 Analog Devices, Inc. All rights reserved.
Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM PRODUCT HIGHLIGHTS TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS TIMING SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TERMINOLOGY TYPICAL PERFORMANCE CHARACTERISTICS APPPLICATIONS INFORMATION CIRCUIT INFORMATION CONVERTER OPERATION MODES OF OPERATION TRANSFER FUNCTIONS TYPICAL CONNECTION DIAGRAM ANALOG INPUTS MULTIPLEXED INPUTS DRIVER AMPLIFIER CHOICE Single-to-Differential Driver VOLTAGE REFERENCE INPUT Internal Reference (PDBUF = Low, PDREF = Low) External 1.2 V Reference and Internal Buffer (PDBUF = Low, PDREF = High) External 2.5 V Reference (PDBUF = High, PDREF = High) Reference Decoupling Temperature Sensor POWER SUPPLY Power Sequencing Power-Up CONVERSION CONTROL INTERFACES DIGITAL INTERFACE RESET PARALLEL INTERFACE Master Parallel Interface Slave Parallel Interface 16-Bit and 8-Bit Interface (Master or Slave) SERIAL INTERFACE MASTER SERIAL INTERFACE Internal Clock SLAVE SERIAL INTERFACE External Clock External Discontinuous Clock Data Read After Conversion External Clock Data Read During Previous Conversion MICROPROCESSOR INTERFACING SPI Interface (ADSP-219x) APPLICATION HINTS LAYOUT EVALUATING THE AD7641 PERFORMANCE OUTLINE DIMENSIONS ORDERING GUIDE