L2340 Datasheet, PDF (1/11 Pages) LOGIC Devices Incorporated – Digital Synthesizer

DEVICES INCORPORATED
DEVICES INCORPORATED
L2340
Digital _LSy₂nt₃he₄si₀zer
Digital Synthesizer
FEATURES
DESCRIPTION
u Digital Waveform Synthesis at
50 MHz
u 24-Bit Polar Phase Angle Accuracy
u User-selectableWaveformSynthesis,
Frequency Modulation, or Phase
Modulation.
u Amplitude Input for Amplitude
Modulation and Gain Adjustment.
u Replaces TRW/Raytheon/Fairchild
TMC2340A
u 120-pin PQFP
The L2340 is a digital synthesizer that
performs waveform synthesis, modu-
lation, and demodulation.
The L2340 automatically generates
quadrature matched pairs of 16-bit
sine and cosine waves in DAC-
compatible 16-bit offset binary format
with15-bit amplitude and 32-bit phase
inputs.
Output waveforms can be phase or
frequency modulated. Digital output
frequencies are restricted to the
Nyquist limit.
Functional Description
The L2340 converts Polar (Phase and
Magnitude) data into Rectangular
(Cartesian) coordinates. The user
selects the numeric format. A valid
transformed result is seen at the
output after 22 clock cycles and will
continue upon every clock cycle
thereafter.
15-bit amplitude and 32-bit phase data
are input into the L2340 to produce an
output of 16-bit rectangular data. The
user may select the data format to
either 16-bit offset binary or 15-bit
unsigned magnitude format. High
accuracy phase increment values with
minimal accumulation error is accom-
plished by use of a 32-bit phase
accumulator.
The phase accumulator structure
supports frequency or phase modula-
tion and is selected by ENP1-0 and
accumulator controls FM and PM.
L2340 BLOCK DIAGRAM
ENA
15
AM14-0
2
ENP1-0
32
PH31-0
FM
PM
OBIQ
CLK
Digital
Synthesizer
OEI
16
I15-0
OEQ
16
Q15-0
Special Arithmetic Functions
1
08/16/2000–LDS.2340-E