High-speed Data Converter
Analog Devices introduces a high-speed A/D converter that extends key converter specifications to new levels. The AD9445 is a 14-bit, 125 MS/s ADC that achieves a spurious-free dynamic range (SFDR) above 80 dBc and a signal-to-noise ratio (SNR) of 72.5 dBfs at input frequencies up to 300 MHz. The SNR characteristics of the AD9445 enable wireless infrastructure equipment designers to improve cellular basestation receivers by offering lower overall system noise at higher intermediate frequencies. Moreover, the combination of high input frequency and high sampling rate eliminates a frequency down-conversion step before the ADC and eases the analog filtering burden. The AD9445 also achieves an aperture jitter of 60 fs (femto seconds), which is critical to maintaining SNR at high input frequencies.
The AD9445 provides high DC accuracy, with typical differential nonlinearity (DNL) of ± 0.2 LSB and integral nonlinearity (INL) of ± 1.0 LSB. The ADC also features a flexible input range up to 3.2 Vp-p, allowing the user to achieve SNR performance as high as 78 dBfs. The AD9445 also has an on-chip reference, track-and-hold and parallel low-voltage differential signaling (LVDS) outputs to ease the interface to digital down-converters.
The ADC requires 3.3 and 5.0 V power supplies and a low voltage differential input clock for full performance operation. No external reference or driver components are required for many applications. Data outputs are LVDS-compatible (ANSI-644) or CMOS-compatible and include the means to reduce the overall current needed for short trace distances. Optional features allow users to implement various selectable operating conditions, including data format select and output data mode.
The AD9445 is optimized for multi-carrier, multi mode receivers such as those found in next generation cellular infrastructure equipment. The device’s high resolution also makes it suitable for antenna array positioning, power amplifier linearization, broadband wireless, radar and infrared imaging, medical imaging, communications instrumentation and software-defined and cognitive radios.
The AD9445-125 and AD9445-105 ADCs are sampling now in a Pb-free, 100-lead TQFP_EP (Thin Quad Flat Pack Exposed Paddle) with production quantities available in September 2005. Pricing for the AD9445-125 and AD9445-105 is $59.50 and $49.30, respectively, in 1,000-unit quantities. The devices are supported by two evaluation boards and a behavioral model that can be used with Analog Devices' ADIsimADC modeling software. For more information, please visit www.analog.com/AD9445.
Analog Devices, Inc.