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| Dual 14-Bit Analog-to-Digital Converter for 3G and WiMAX Released Analog Devices has introduced the first dual 14-bit analog-to-digital converter to achieve sampling rates of 150 mega samples per second. Supporting all third-generation base station wireless standards, including W-CDMA, CDMA2000 and TD-SCDMA, the AD9640 is the only dual 14-bit ADC that samples at rates beyond 135 MSPS, a common requirement for the emerging WiMAX standard. Prior to the AD9640, sampling rates beyond 135 MSPS could only be realized by utilizing single-channel ADCs. With the AD9640, base station designers are able to reach higher sampling rates with one dual ADC, enabling a 50 percent reduction in board space requirements. Additionally, the AD9640 simplifies the design of multicarrier wireless infrastructure systems by decreasing the amount of analog filtering in front of the ADC and offering low power consumption. The new ADC delivers high performance, while only consuming 390 mW of power per channel. The AD9640 offers signal-to-noise ratio of 72.7 dBFS and spurious free dynamic range of 85 dBc with a 70 MHz intermediate frequency, and is also capable of supporting IFs as high as 450 MHz, enabling WiMAX designers to use a single downconversion receiver design instead of the traditional two downconversion stages. For optimal performance, the AD9640 can be driven with ADI's AD8352 low distortion differential amplifier. The AD9640 divides the input clock by an integer between 1 and 8, reducing system complexity and improving clock jitter. In a traditional base station transmitter, the digital-to-analog converters, such as ADI's AD9779, will have a higher clock rate, which is divided down to match the ADC. By implementing the clock divider on-chip, the AD9640 eliminates the need for an external divider. In addition, the phase noise of the source improves in proportion to the divide ratio. write your comments about the article :: © 2006 Networking News :: home page |