mega138Overview. Tang Mega 138K uses a 22nm process GW5AST-LV138PG484A FPGA chip, which has 138,240 lookup table units and nearly 300 DSP units. It contains eht hhHardware Resources. Board Specification Board Schematic PCB BOM Board Dimension Diagram Board 3D Model Some Chip Manuals. Getting Started. Note that 138K