Ryan M Sutton - Random Projects and Comments
Ryan M Sutton - Random Projects and Comments
The development board I chose for this project is the Lattice MachOX2 board. (P/N: LCMXO2-7000HE-B-EVN ) Its a very simple board, cheap, and easily obtainable from a supplier I already use. It doesn’t have a lot on the board, the MachOX2 has an internal oscillator, core voltage regulator, and configuration flash both of which they take advantage of on the eval board. All that they need to get the chip up and running is an IO voltage regulator (3.3v in this case) and a FTDI chip for programming. They a
Even though the MachOX2 has an internal oscillator there is a7.0mm x 5.0mm 4-SMD footprint for a oscillator which routes to pin 27 at a 3.3v logic level. From what I could figure out the internal oscillator couldn’t be routed on a primary clock path, so I fitted a 48mhz oscillator to the board. I was likely to need an external clock anyways since the internal one may not be stable enough for the high speed serialization.
Another modification I made to the board was to change one of the IO supply voltages. The default configuration is that all of the IO banks are fed with 3.3v across a 1 ohm resistor. There are two advantages to this, by measuring the voltage drop across that resistor you can determine the current you’ll need if you move your design to a custom PCB. The second being by removing that resistor you can feed a different IO voltage to any bank you like ( or just a higher current supply if necessary). Details
Ryan M Sutton - Random Projects and Comments
Ryan M Sutton - Random Projects and Comments