High-Speed Data Converters and IF Diversity Receivers From Analog Devices Maximize Receiver Sensitivity and
Dynamic Range for 3G and 4G Cellular Base Stations
NORWOOD, Mass.--(BUSINESS WIRE)--
Analog Devices Inc. (ADI) today introduced four high-speed data converter products that support signal
sampling rates necessary to accommodate
multi-carrier radio platform requirements for today’s 3G and 4G cellular infrastructure communication
standards, including CDMA2000, UMTS/LTE, TD-SCDMA and TD-LTE.
AD6643 IF diversity receivers and
AD9613 high-speed A/D converters complement other receive chain components to simplify control loops and
maximize base station receiver sensitivity and dynamic range. When paired with ADI’s dual-channel
ADL5202 VGA (variable gain amplifier), the AD6649 IF receiver ensures that both weak and strong incoming cell
phone call signals are effectively received and processed. The VGA is directly controlled by the AD6649 which can
use the 1-dB gain step resolution in a simplified AGC (automatic gain control) loop.
About the AD6649 and AD6643 IF Diversity Receivers The AD6649 is the industry’s first
IF diversity receiver able to monitor the incoming signal power and adjust the VGA gain setting directly
without the need for a microprocessor. The AD6649 integrates many of the functions required for a diversity
receive path in a single device, including an ultra-low-latency peak detector and a rms signal power monitor.
There is also an integrated DDC (digital down converter) that includes a 32-bit NCO (numerically controlled
oscillator), a decimating half-band filter and an output FIR (finite-impulse response) filter that provides an
effective band-pass filtering function and reduces the output rate.
The AD6643 is an IF diversity receiver for cost-sensitive applications that integrates two high performance
A/D converters and noise shaping requantizer (NSR) digital blocks. The integrated NSR circuitry allows for
improved SNR (signal to noise ratio) performance in a smaller frequency band within the Nyquist bandwidth. With
the NSR feature enabled, the outputs of the A/D converters are processed such that the AD6643 supports enhanced
SNR performance within a limited portion of the Nyquist bandwidth while maintaining 11-bit output resolution. The
NSR block can be programmed to provide a bandwidth of either 22 percent or 33 percent of the sample clock.
About the AD9643 and AD9613 High Speed A/D Converters For wideband, multi-carrier wireless
communications applications that require only a dual A/D converter function without DDC functionality due to cost
or size constraints, ADI introduced the AD9643 14-bit A/D converter with sampling speeds up to 250 MSPS. The
AD9643 A/D converter features a multi-stage, differential pipelined architecture with integrated output error
correction logic. Wide bandwidth inputs support a variety of user-selectable input ranges, while an integrated
voltage reference eases design considerations. Programming for setup and control are handled using a three-wire
SPI-compatible serial interface. ADI also released today the 12-bit, pin-compatible AD9613 A/D converter, which
achieves sampling speeds up to 250 MSPS.