4
MachXO Standard Evaluation Board
Lattice Semiconductor
Revisions 001 & 002 User’s Guide
Figure 1. MachXO Standard Evaluation Board
Power Supply
The MachXO Standard Evaluation Board includes two locations to apply power. On the east side of the board are a
pair of banana jacks (JP28 and JP29) and a coaxial DC connector (JP30), which receive power from either a bench
power supply or a brick style power supply. A DC source between 5.0V and 28.0V must be applied in order to
power the board. The coaxial DC connector uses a 2.5mm central pin, with a 6.3mm outer diameter barrel.
The output from the DC system is controlled by switch S5. Switch S5 is in the southeast corner of the board. This is
a small surface mount switch that enables and disables the LTC1775 DC-DC conversion chip. The output voltages
from the power supply are enabled when the switch is in the “on” position.
The 5.0V to 28.0V DC input voltage is converted by DC-DC converters and switching power supplies to provide
3.3V, 1.2V, and an adjustable DC source on the board. The output from these supplies travels through surface
mounted fuse holders. Fuses are supplied and prevent over-current conditions from damaging the components on
the board (Vendor: Littlefuse, Make: Nano SMF Very Fast Acting, 1.5A or 3A).
Due west of the fuse blocks are more banana plug connectors. These connectors provide an alternate means for
applying DC voltage levels to the board. To apply voltages not supplied by the on-board power section,
first
remove the appropriate fuse from the fuse holder
. Then connect an alternate DC supply to the banana plug
connector associated with that fuse.
Table 1. Power Supply Fuses
Fuse Number
Supply Rail
Enabled/Disabled
Banana Connector
Input
F1
V
ADJ
JP25
F2
1.2V
JP26
F3
3.3V
JP27
RJ-45
Connector
Area
SMA
Connector
Area
ispClock5610
DIP Oscillator
8-Bit Input
Switch
Push-Button
Switches
Prototype
Areas
LCD Display
Area
DC Power
Input Jack
Power
Inputs
North
South
East
West
Prototype
Area
JTAG Pro
g
rammin
g
Interface
