Looks like an ADC & FIFO memory to store samples? Possibly from oscilloscope or waveform digitizer?

Larger die looks like FIFO or sample memory; middle section is omitted from images.

mz_die1_btm-edge

• Single (12181×1962, 12.4713MiB)

mz_die1_top-edge

• Single (12222×1949, 10.8902MiB)

Smaller die looks like ADC

mz_die2_overview

• Single (6512×4435, 13.6009MiB)

mz_die2_zoom

• Single (2705×2702, 2.58696MiB)