L2340
DEVICES INCORPORATED
Digital Synthesizer
Outputs
L2340 FUNCTIONAL BLOCK DIAGRAM
I15-0 — x-coordinate Data Output
AM14-0
ENA
PH31-0
ENP1-0
2
FM
PM
I15-0 is the 16-bit Cartesian x-coordi-
nate Data output port. When OEI is
HIGH, I15-0 is forced into the high-
impedance state. I15 is forced HIGH if
OBIQ is LOW.
15
32
32
M
C
AM
Q15-0 — y-coordinate Data Output
Q15-0 is the 16-bit Cartesian y-coordi-
nate Data output port. When OEQ is
HIGH, Q15-0 is forced into the high-
impedance state. Q15 is forced HIGH
if OBIQ is LOW.
32
PM
FM
32
32
24
24
Controls
15
15
ENA — Amplitude Modulation Data
Input Enable
When ENA is HIGH, AM is latched
into the input register on the rising
edge of clock. When ENA is LOW, the
value stored in the register is un-
changed.
*TRANSFORM
PROCESSOR
OBIQ
16
16
16
16
ENP1-0 — Phase Modulation Data Input
Control
OEI
OEQ
ENP1-0 is the 2-bit Phase Modulation
Data Input Control that determines
one of the four modes shown in Table
1. ‘M’ is the Modulation Register and
‘C’ is the Carrier Register as shown in
the Functional Block Diagram.
I
15-0
Q
15-0
*REQUIRES 18 CYCLES TO COMPLETE AND IS FULLY PIPELINED
SIGNAL DEFINITIONS
Power
Inputs
AM14-0 — Amplitude Modulation Data
Input
TABLE 1. REGISTER OPERATION
Vcc and GND
ENP1-0 Configuration
AM14-0 is the 15-bit Amplitude
Modulation Data input port. AM14-0
is latched on the rising edge of CLK.
+5V power supply. All pins must be
connected.
0 0
0 1
1 0
1 1
No registers enabled, current data held
M register input enabled, C data held
C register input enabled, M data held
M register = 0, C register input enabled
Clock
PH31-0 — Phase Angle Data Input
CLK — Master Clock
PH31-0 is the 32-bit Phase Angle Data
input port. Input phase accumulators
are loaded through this port into
registers enabled by ENP1-0. PH31-0 is
latched on the rising edge of CLK.
The rising edge of CLK strobes all
enabled registers.
TABLE 2. ACCUMULATOR CONTROL
FM PM Configuration
0
0
1
1
0
1
0
1
No accumulation (normal operation)
PM accumulator path enabled
FM accumulator path enabled
Logical OR of PM and FM (Nonsensical)
Special Arithmetic Functions
08/16/2000–LDS.2340-E
2
LOGIC [ LOGIC DEVICES INCORPORATED ]
