Programmable TTL and Direct Digital Synthesis RF
Pulse Generator
Models and Ordering Information
Sample Part Number:
PBDDS-I-300-USB.
Model
Price
Order
PBDDS-I-300-USB
1 RF output channel
300 MHz clock frequency
4k memory words
USB
$2495
PulseBlasterDDSTM is a
general-purpose, intelligent, programmable, RF
and TTL/CMOS pulse/pattern generator system (USB
board). The PulseBlasterDDSTM
series of Intelligent Pulse Generation boards
from SpinCore Technologies, Inc., couples
SpinCore's unique Intelligent Pulse Timing
Processor core, dubbed PulseBlasterTM,
with Direct Digital Synthesis (DDS) technology
for use in system control and radio-frequency
(RF) pulse generation. The PulseBlasterTM
processor, implemented in state-of-the-art
programmable logic, provides all the necessary
timing control signals required for overall
system control and pulse synchronization.
By adding DDS features, PulseBlasterDDSTM
can now meet all the excitation/stimuli needs of
demanding users. PulseBlasterDDSTM
provides users the ability to control their
systems through the generation of both digital
control signals and fully synchronized
excitation RF pulses from a small form factor PC
board, providing users a compelling
price/performance proposition unmatched by any
other device on the market today.
Architecture
This figure
presents the general architecture of the
PulseBlasterDDS-I-300 system. The major building
blocks are the DDS Core and the Pulse
Programming and Timing Processor Core (PP Core).
The DDS Core contains a Numerically Controlled
Oscillator (NCO), 8 programmable phase
registers, 1024 programmable frequency
registers, the AWG (Arbitrary Waveform
Generator), and the adjustable attenuator.
The PP Core controls the timing of the gating
pulses and provides the necessary control
signals for frequency and phase registers.
The DDS and PP cores have been integrated onto a
single silicon chip. High performance DAC
chips and high current output amplifiers
complement the design.
Benefits of DDS Technology
Generation of any frequency from DC (Direct
Current) to 1/2 reference clock oscillator in
milliHertz tuning steps (32 bit digital
resolution)!
Agile relative phase control using up to 8
programmable phase registers per channel,
12-bit phase resolution. Pipeline delay
of only 3 reference clock cycles.
Agile, phase coherent, "zero-time" frequency
switching using 1024 independent frequency
registers.
Greater immunity to parameter drift due to
temperature.
What does SpinCore's
Intelligent Pattern Generation give users?
Timing resolution of 13.3 ns with a 50 MHz
external clock (NOTE: Timing resolution of 2.5
ns is available on non-DDS, TTL-only
PulseBlasterESR boards operating up to 400
MHz).
4 individually controlled output bits.
Simple instruction set.
Memory space for up to 4k program words
(VLIW, 80-bit wide).
External hardware and software triggering.
3.3 V digital TTL/CMOS outputs, 25 mA per
pin. Output bits can be combined to
increase the max. load current.
Multi-board synchronization.
Added benefits
Small size and low power consumption.
Low level and high level programming
support.
Free technical support; extended support
available.
Output Signals
This exciting product comes with one analog
output channels and 4 TTL/CMOS channels, all
individually controlled and
synchronized. The analog channel can
output RF/IF frequencies down to programmable DC
levels. By providing multiple options,
PulseBlasterDDSTM can be your
complete excitation device for NMR, NQR, MRI, or
related resonance and test technologies.
If more output channels are required, multiple
boards can be synchronized to provide as many
digital output bits or RF/IF channels as
necessary. The frequency and phase of the
RF pulses generated by the DDS output channel
are under the complete control of the user and
are specified through software programming.
Digital sampling rates of the output waveforms
up to 300 MHz are supported.
External Triggering and
Cascading
PulseBlasterDDSTM can be triggered
and/or reset externally via dedicated hardware
lines. The two separate lines combine the
convenience of triggering (e.g., in cardiac
gating) with the safety of the
"stop/reset-to-zero" line. The required
control signals are active low (or short to
ground). The design also allows for
multiple boards to be synchronized, easily
extending the available output pattern to more
bits and/or more RF/IF channels. The
"Wait-for-event" feature is standard.
Applications
Complex, high-speed, multi-channel
pulse, pattern, and word generation.
Customers' applications have included
Complete high IF digital excitation system
for high field NMR/MRI (just add mixers!).
Complete bench test equipment for
solid-state NMR probes (just add mixer and
power amplifier!) - eliminates the need for
wasting the precious magnet time.
Build a multi-qubit NMR quantum computing
device at a fraction of the cost of other
solutions.
Use it for all-digital CRAMPS, SFAM, and
other "exotic" solid-state NMR experiments.
Build a lock system.
Build a demostration NMR system with/for
your students
Use it for Senior-Project and Masters'
classes.
Use with your microcoil probe.
Build and control your own equipment for
"hyphenated" experiments, LC-NMR, etc.
Spin-Decoupler. Autonomous,
pre-programmed RF generator customized for
NMR/MRI decoupling applications. To
simplify the pulse-sequence programming, WALTZ
and MLEV decoupling sequences are hard-coded
via firmware and can be selected with an
external TTL signal. The RF output
frequency and pulse lengths can be controlled
via a simple ASCII RS232 serial
interface. The RF output power is
approx. 10 dBm.
Clock Generator. Single
square-wave output of DDS-derived
frequencies, 32 bits of frequency precision
(141 mHz at 300 MHz reference oscillator
frequency), may be used for driving digital
systems as a digital clock generator;
simplified programming interface.
To complement the power and performance of the
PulseBlasterDDSTM board, the software
programming of the board is
straightforward. The programming
architecture, based on the
Very-Long-Instruction-Word (VLIW) concept,
assures that all RF and DAC events are always
properly synchronized with the timing control
signals generated by PulseBlasterTM
pulse programmer core. The 32k memory
depth and powerful flow control statements allow
the most complicated patterns/sequences to be
executed with ease. The PulseBlasterDDSTM
board can run under Microsoft Windows operating
systems, including XP. The control
software can be compiled to operate under other
operating systems as well.
Free Software Support
Available as a part of the SpinAPI Package:
Example programs (executables and C source
files)
The SpinAPI package available for download
on the Software Downloads
page.
This is a demonstration of the simultaneous
frequency and amplitude sweeping capabilities of
the SpinCore Technologies'
PulseBlasterDDS-I-300. The video shows a chirped
pulse with a frequency sweep from 80 to 2 MHz
and a Gaussian amplitude profile.