Lattice Semiconductor MachXO2 Breakout Board, Руководство пользователя

Страница: 21 / 33

MachXO2 Breakout Board Evaluation Kit
Evaluation Board User Guide
© 2014-202
2
Lattice Semiconductor Corp. All Lattice trademarks, registered trademarks, patents, and disclaimers are as listed at www.latticesemi.com/legal .
All other brand or product names are trademarks or registered trademarks of their respective holders. The specifications and information herein are subject to change without notice.
FPGA-EB-02051-2.3 21
7.3. Board Modifications
This section describes modifications to the board to change or add functionality.
7.3.1. Bypassing the USB Programming Interface
The USB programming interface circuit ( USB Programming and Debug Interface section) may be optionally by-passed
by removing the 0 ohm resistors: R5, R6, R7, R8 (See Appendix A. Schematic Diagram , Sheet 2 of 5). Header landing J1
provides JTAG signal access for jumper wires or a 1 × 8 pin header.
7.3.2. Applying External Power
The Breakout Board is powered by the circuit of Schematic Sheet 5 of 5 based on the 5 V USB power source. You may
disconnect this power source by removing the 0
Ω resistors: R42 (VCC_1.2 V) and R44 (VCC_3.3 V). Power connections
are available from the expansion header landings, J3 (+1.2 V, pins 1 and 3, schematic sheet 3 of 5) and J4 (+3.3 V, pins 1
and 3, schematic sheet 4 of 5).
7.3.3. Measuring Bank and Core Power
In addition to the expansion headers, test points (TP1, TP2) provide access to power supplies of the MachXO2 FPGA.
Inline 1 ohm resistors: R24 (VCCIO0, +3.3 V, Bank 0), R25 (VCCIO1, +3.3 V, Bank 1), R26 (VCCIO2, +3.3 V, Bank 2), R27
(VCCIO3, +3.3 V, Bank 3), R56 (VCC core, +1.2 V) can be used to measure current for the power supplies. VCCIO3 (Bank
3), VCCIO4 (Bank 4) and VCCIO5 (Bank 5) in the current version of the board with LCMXO2-7000HE-4TG144C device are
all connected to the same +3.3V supply.
7.4. Mechanical Specifications
Dimensions: 3 in. [L] × 3 in. [W] × 1/2 in. [H]
7.5. Environmental Requirements
The evaluation board must be stored between -40° C and 100° C. The recommended operating temperature is between
0° C and 90° C.
The board can be damaged without proper anti-static handling.
7.6. Glossary
FPGA — Field Programmable Gate Array
DIP — Dual in-line package
LED — Light Emitting Diode.
LUT — Look Up Table
PCB — Printed Circuit Board
RoHS — Restriction of Hazardous Substances Directive
USB — Universal Serial Bus
WDT — Watchdog Timer