Introduction – Sundance SMT941 User Manual
Page 6
User Manual SMT941
Page 6 of 43
Last Edited: 23/08/2011 17:24:00
Introduction
The SMT941 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 Analog-to-Digital Converters
The
SMT941 implements a comprehensive clock circuitry based on a distribution chip
from Texas Instrument that allows synchronisation among the
converters and the use of an internal/external reference clock or internal/external
sampling clock. It provides a complete conversion solution and stands as a platform
that can be part of a transmit/receive communication platform. The SMT941 has an
on-board VCXO of frequency 245.76MHz.
ADCs have a resolution of 14 bits and are able to update outputs at up to 250MHz.
All converters are 1.8/3.3-Volt. ADCs internal gain and offset can be adjusted as
well as the data format. ADCs are AC-coupled on the board using a double-
transformer structure. 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 SMT351T) on the base module can be used to store incoming
samples.
Converter configuration, sampling and transferring modes are set via internal
control registers stored inside the FPGA and accessible via Comport.
The SMT941 module is well-suited for multi-carrier, wide bandwidth communication
applications.
Note that the SMT941 requires to be coupled with an SLB base module set to work
with 2.5V FPGA IOs.
The main features of the SMT941 are listed below:
● Two Dual 14-bit 250MSPS ADC
● On-board low-jitter clock distribution chip
● On-board 245.76MHz VCXO,
● On-board 10MHz reference crystal,
● One external clock, and one reference clock inputs vi
connector,
● One external clock output vi
connector,
● One external trigger input vi
connector (can also be used as an
output),
● On
connector to link SMT941 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.
● A fan.