Sundance SMT942 User Manual
Page 7
User Manual SMT942
Page 7 of 55
Last Edited: 23/08/2011 17:25:00
Introduction
The SMT942 is a single width expansion TIM that plugs onto a
base module,
(Virtex-5 LXT, SXT or even FXT FPGA) as an example and incorporates
2 Texas Instrument dual-channel Digital-to-Analog Converters
The
SMT942 implements a comprehensive clock circuitry based on a chip
from Texas instrument that allows synchronisation among the converters and the
use of an external reference clock or sampling clock. It provides a complete
conversion solution and stands as a platform that can be part of a transmit/receive
base station. The SMT942 has an on-board VCXO of frequency 245.76MHz.
DACs have a resolution of 16 bits and are able to update outputs at up to
800MSamples per second. All converters are 1.8/3.3-Volt. Among the features of the
DAC5688 are integrated interpolation filters, a fine frequency mixer with a complex
NCO, a clock multiplier and IQ compensation. No DC-coupled version is currently
available.
(Virtex-5 LXT or SXT series in the case of the SMT351T) on the base
module is responsible for handling data coming from one of the following sources:
Comports or Rocket Serial Link
These interfaces are compatible with a wide
range of Sundance’s modules.
The memory (DDR2) on the base module (still based on the case where using an
SMT351T SLB base module) can store outgoing samples.
Converter configuration, sampling and transferring modes are set via internal
control registers stored inside the FPGA and accessible via Comport.
The SMT942 module is well-suited for multi-carrier, wide bandwidth communication
applications.
The main features of the SMT942 are listed below:
● Two Dual 16-bit 800MSPS DAC
● On-board low-jitter clock distribution chip
● On-board 491.52MHz VCXO,
● On-board 10MHz reference crystal,
● One external clock, one external trigger and one reference clock inputs via
connector,
● One external clock output vi
connector,
● On
connector to link SMT942 and SMT351T as an example,
● All Analogue inputs to be connected to 50-Ohm sources.
● All Analogue outputs to be connected to 50-Ohm loads.
● Optional fan.