Pleora Technologies iPort NTx-Pro, Hardware Manual, Page: 28 / 52

24 Connector: User Circuitry: 2x 50-pin FFC/FPC
Copyright © 2010 Pleora Technologies Inc.
FPGA Selection Pins
There are two circuit configuration options for selecting the main and backup loads.
Option 1 indicates the use of dipswitches to select the main load or backup load in the figure below.
FPGA
NTx-Pro Board
R1
R2
2.5V
2.5V
FPGA_SEL0
R3
R4
470K Ω
470 K Ω
NOTES
1. R1, R2, internal pull -ups; 8K Ω to 61K Ω (35K Ω typical).
2. R3, R4, on-board pull -downs , 470 K Ω .
3. Option 1: Use dipswitches SW1/SW2 to select main/backup load .
FPGA_SEL1
4. Use for pull-up/pull-down resistors R value 1K Ω or less
1K
Ω
2.5V/3.3V
1K Ω
SW1
R
R
FPGA Main/Backup Load Selection : Option 1
1K Ω
2.5V/3.3V
1K Ω
SW2
R
R
Option 2 indicates the use of a jumper to select the backup load in the figure below.
FPGA
NTx-Pro Board
R1
R2
2.5V
2.5V
FPGA_SEL0
R3
R4
470K Ω
470 K Ω
NOTES
1. R1, R2, internal pull -ups; 8K
Ω
to 61K
Ω
(35K
Ω
typical).
2. R3, R4, on-board pull -downs , 470 K Ω .
3. Option 2: Short jumpers J 1/J2 to select the backup load .
FPGA_SEL1
4. Use for pull-up resistors R value 1K Ω or less.
1K Ω
2.5V/3.3V
J1
R
FPGA Main/Backup Load Selection : Option 2
1K Ω
2.5V/3.3V
J2
R
Optional jumper for Backup Load