LFE3-95EA-V-EVN Lattice, LFE3-95EA-V-EVN Datasheet - Page 24

• Manufacturer Part Number: LFE3-95EA-V-EVN
• Description: Programmable Logic IC Development Tools LatticeECP3-95EA Video Protocol Board
• Manufacturer: Lattice
• Type: FPGAr

Specifications of LFE3-95EA-V-EVN

• Rohs: yes
• Product: Evaluation Boards
• Tool Is For Evaluation Of: LFE3-95E-7FN1156C
• Interface Type: DVI
• Operating Supply Voltage: 12 V
• Description/function: LatticeECP3 Video protocol board
• Factory Pack Quantity: 1

Table 34. Logic Analyzer Connections (J29, J35 and J36) (Continued)
Known Issues
1. DDR2 Reference Voltage
There are two DDR2 devices on the board – U29 and U31. When the design is using only one DDR2 device,
the DDR2_REF signal for the unused DDR2 device will be pulled up by the unused LatticeECP3 pin. This pulls
the Vref voltage away from the 0.9V generated by the LP2997 voltage regulator to around 1.6~1.7V. The
DDR2 will not work with the wrong reference voltage; the DDR2 accesses will fail. The DDR2_REF generated
by LP2997 is connected to LatticeECP3 pin-V7(VREF1 of Bank 6 for the DDR2 device on U29) and pin-R9
(VREF1 of Bank 7 for the DDR2 device on U31). To avoid being pulled up to the wrong voltage, the unused
VREF1 pin cannot be left unused because all unused pins will be pulled up by default. The easiest workaround
is adding dummy logic with one input and one output, and then assigning this input pin to the unused VREF1
pin.
J29 Pin #
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
9
Signal
LA10
LA11
LA12
LA13
LA14
LA15
LA16
LA17
LA18
LA19
LA20
LA21
LA22
LA23
LA24
LA25
LA26
LA27
LA28
LA29
LA30
LA31
LA32
LA33
LA34
LA5
LA6
LA7
LA8
LA9
J35 Pin #
10
11
12
13
14
15
16
17
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
3
4
5
6
7
8
9
LatticeECP3 Video Protocol Board – Revision C
24
J36 Pin #
—
—
—
—
—
—
—
10
—
11
—
12
—
13
—
14
—
15
—
16
—
17
—
3
4
5
6
7
8
9
LatticeECP3
Pin #
AM5
AM6
AM4
AN6
G23
A24
B24
H22
H23
K23
K24
C28
D28
G26
AA2
AL8
AL7
AP5
AP6
F22
AJ6
J22
J23
—
—
—
—
—
—
—
User’s Guide
LatticeECP3 I/O
Bank (Voltage)
Bank 1 (2.5V)
Bank 6 (1.8V)
—
—
—
—
—
—
—