JUNE 13--Analog Devices Inc. (Norwood, MA; www.analog.com) is now offering what it believes is the fastest 12-bit analog-to-digital converter (ADC) on the market, capable of encoding at 210 Msamples/s. The AD9430 is reportedly 68% faster than the next fastest available converter. The ADC has the precision and speed required to support the next generation of communications and high-end imaging applications. These applications include broadband cable-modem head-end systems, 3G radio transceivers, as well as high-data-rate point-to-point radios, medical imaging Systems, and spectrum analyzers.
For cable modems, the Euro-DOCSIS (data over cable service interface specification) standard uses a larger return path spectrum--requiring higher performance data converters--than the North American DOCSIS standard. With the AD9430, cable system OEMs can create a cost-effective, worldwide universal analog front end for reverse path deployment, eliminating the need for unique systems for different regions. Also, studies have proven that digitizing the cable return path increases the overall cable plant reliability by eliminating traditional analog effects such as temperature drift. Digitizing the return path also simplifies maintenance since systems can use multi-sourced standards-based digital components. This product achieves the performance required to deliver higher-order modulation schemes so that cable service providers can offer a new suite of revenue-generating services, such as telephony, gaming, video conferencing, and guaranteed data rates.
In addition, the AD9430 allows designers to increase data rates in radio point-to-point systems by migrating to high orders of modulation-from PSK-based to QAM or OFDM, which have higher spectral requirements--or by increasing the spectrum bandwidth, up to 105 MHz, thanks to the fast sample rate of the AD9430. In cellular infrastructure transmit systems, designers can use the AD9430 to take advantage of digital pre- distortion techniques for 3G systems that require digitization of the entire multicarrier transmitted spectrum in a band up to 70 MHz.
The AD9430 is a 12-bit monolithic sampling ADC with an on-chip track-and-hold circuit optimized for speed, low power, small size, and ease of use. The device has excellent signal-to-noise-ratio performance of 64 dB up to 65 MHz at 210 Msamples/s and spurious free dynamic range of 80 dBc up to 65 MHz at 210 Msamples/s.