Datasheet AD9281 (Analog Devices)

a
Dual Channel 8-Bit Resolution CMOS ADC AD9281 FEATURES FUNCTIONAL BLOCK DIAGRAM Complete Dual Matching ADC Low Power Dissipation: 225 mW (+3 V Supply) AVDD AVSS CLOCK DVDD DVSS Single Supply: 2.7 V to 5.5 V IINA Differential Nonlinearity Error: 0.1 LSB "I" ADC I AD9281 SLEEP REGISTER On-Chip Analog Input Buffers IINB SELECT On-Chip Reference IREFB REFERENCE BUFFER Signal-to-Noise Ratio: 49.2 dB IREFT THREE- Over Seven Effective Bits QREFB ASYNCHRONOUS STATE DATA QREFT MULTIPLEXER OUTPUT 8 BITS Spurious-Free Dynamic Range: –65 dB VREF BUFFER 1V No Missing Codes Guaranteed REFSENSE 28-Lead SSOP CHIP QINB SELECT "Q" ADC Q QINA REGISTER PRODUCT DESCRIPTION PRODUCT HIGHLIGHTS
The AD9281 is a complete dual channel, 28 MSPS, 8-bit 1. Dual 8-Bit, 28 MSPS ADC CMOS ADC. The AD9281 is optimized specifically for applica- A pair of high performance 28 MSPS ADCs that are opti- tions where close matching between two ADCs is required (e.g., mized for spurious free dynamic performance are provided for I/Q channels in communications applications). The 28 MHz encoding of I and Q or diversity channel information. sampling rate and wide input bandwidth will cover both narrow- 2. Low Power band and spread-spectrum channels. The AD9281 integrates Complete CMOS Dual ADC function consumes a low two 8-bit, 28 MSPS ADCs, two input buffer amplifiers, an internal 225 mW on a single supply (on 3 V supply). The AD9281 voltage reference and multiplexed digital output buffers. operates on supply voltages from 2.7 V to 5.5 V. Each ADC incorporates a simultaneous sampling sample-and- 3. On-Chip Voltage Reference hold amplifier at its input. The analog inputs are buffered; no The AD9281 includes an on-chip compensated bandgap external input buffer op amp will be required in most applica- voltage reference pin programmable for 1 V or 2 V. tions. The ADCs are implemented using a multistage pipeline architecture that offers accurate performance and guarantees no 4. On-chip analog input buffers eliminate the need for external missing codes. The outputs of the ADCs are ported to a multi- op amps in most applications. plexed digital output buffer. 5. Single 8-Bit Digital Output Bus The AD9281 is manufactured on an advanced low cost CMOS The AD9281 ADC outputs are interleaved onto a single process, operates from a single supply from 2.7 V to 5.5 V, and output bus saving board space and digital pin count. consumes 225 mW of power (on 3 V supply). The AD9281 6. Small Package input structure accepts either single-ended or differential signals, The AD9281 offers the complete integrated function in a providing excellent dynamic performance up to and beyond compact 28-lead SSOP package. 14 MHz Nyquist input frequencies. 7. Product Family The AD9281 dual ADC is pin compatible with a dual 10-bit ADC (AD9201). REV. F Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
use, nor for any infringements of patents or other rights of third parties
Tel: 781/329-4700 World Wide Web Site: http://www.analog.com
which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Fax: 781/461-3113
©1999-2011 Analog Devices, Inc. All rights reserved.