English
Language : 

M1A3P1000-1PQ208M Datasheet, PDF (104/212 Pages) Microsemi Corporation – Military ProASIC3/EL Low Power Flash FPGAs with Flash*Freeze Technology
Military ProASIC3/EL DC and Switching Characteristics
B-LVDS/M-LVDS
Bus LVDS (B-LVDS) and Multipoint LVDS (M-LVDS) specifications extend the existing LVDS standard to
high-performance multipoint bus applications. Multidrop and multipoint bus configurations may contain
any combination of drivers, receivers, and transceivers. Microsemi LVDS drivers provide the higher drive
current required by B-LVDS and M-LVDS to accommodate the loading. The drivers require series
terminations for better signal quality and to control voltage swing. Termination is also required at both
ends of the bus since the driver can be located anywhere on the bus. These configurations can be
implemented using the TRIBUF_LVDS and BIBUF_LVDS macros along with appropriate terminations.
Multipoint designs using Microsemi LVDS macros can achieve up to 200 MHz with a maximum of 20
loads. A sample application is given in Figure 2-27. The input and output buffer delays are available in
the LVDS section in Table 2-159 on page 2-88.
Example: For a bus consisting of 20 equidistant loads, the following terminations provide the required
differential voltage, in worst-case Industrial operating conditions, at the farthest receiver: RS = 60  and
RT = 70 , given Z0 = 50  (2") and Zstub = 50  (~1.5").
Receiver
EN
R
+
-
Transceiver
EN
T
+
-
Driver
D EN
+
-
Receiver
EN
R
+
-
RS RS
RS RS
RS RS
RS RS
Zstub
Z0
Zstub
Zstub
Z0
Zstub
Zstub
Z0
Zstub
Zstub
Z0
Zstub ...
RT Z0
Z0
Z0
Z0
Transceiver
EN
T
+
-
RS RS
BIBUF_LVDS
Z0
Z0
Z0
Z0
RT
Figure 2-27 • B-LVDS/M-LVDS Multipoint Application Using LVDS I/O Buffers
2-90
Revision 3