Lattice Semiconductor iCE40 UltraPlus 8:1 Microphone Aggregator Board (LF-81AGG-EVN) is an optional add-on Daughter Board for the iCE40 UltraPlus Mobile Development Platform (MDP). The LF-81AGG-EVN Board features eight PDM microphones, with six arranged in a 67mm diameter hex pattern, and two near the center.