S27KL0642DPBHI023 is a 64 Mb HYPERRAM self-refresh DRAM (PSRAM) with a HYPERBUS interface using CS#, CK, 8-bit DQ, RWDS, and RESET#. It runs from a 2.7 V to 3.60 V VCC supply, supports up to 166 MHz DDR transfers, and is specified for -40°C to +105°C (AEC-Q100 Grade 2). Configurable linear or wrapped bursts (16 to 128 bytes) plus deep power-down of 15 µA at 3.6 V, 105°C support fast external memory expansion.