The MT25Q is a high-performance multiple input/output serial Flash memory device. It features a high-speed SPI-compatible bus interface, execute-in-place (XIP) functionality, advanced write protection mechanisms, and extended address access. Innovative, high-performance, dual and quad input/output commands enable double or quadruple the transfer bandwidth for READ and PROGRAM operations. Key Features
Stacked device (two 512Mb die) SPI-compatible serial bus interface Single and double transfer rate (STR/DTR) Clock frequency 166 MHz (MAX) for all protocols in STR 90 MHz (MAX) for all protocols in DTR Dual/quad I/O commands for increased throughput up to 90 MB/s Supported protocols in both STR and DTR Extended I/O protocol Dual I/O protocol Quad I/O protocol Execute-in-place (XIP) PROGRAM/ERASE SUSPEND operations Volatile and nonvolatile configuration settings Software reset Additional reset pin for selected part numbers 3-byte and 4-byte address modes enable memory access beyond 128Mb Dedicated 64-byte OTP area outside main memory Readable and user-lockable Permanent lock with PROGRAM OTP command Erase capability Die erase Sector erase 64KB uniform granularity Subsector erase 4KB, 32KB granularity Security and write protection Volatile and nonvolatile locking and software write protection for each 64KB sector Nonvolatile configuration locking Password protection Hardware write protection: nonvolatile bits (BP[3:0] and TB) define protected area size Program/erase protection during power-up CRC detects accidental changes to raw data Electronic signature JEDEC-standard 3-byte signature (BB21h) Extended device ID: two additional bytes identify device factory options JESD47H-compliant Minimum 100,000 ERASE cycles per sector Data retention: 20 years (TYP)
苹果进入降噪耳机市场的想法也并非无迹可寻。
2014 年，苹果斥资 30 亿美元收购了耳机品牌 Beats，这是苹果有史以来规模最大的一次收购，Beats 的加入也成为苹果进入高端耳机市场的敲门砖。随后分别在 2016 年和 2017 年登场的 AirPods 和 HomePod 则进一步帮助苹果在音乐硬件领域站稳脚跟。去年，调查机构 Counterpoint Research 就曾发布一份报告，指出苹果在 2018 年卖出大约 3500 万副 AirPods 无线耳机，AirPods 逐渐成为 Hearable（智能耳戴式设备）的代表。前有 Beats 负责高端时尚耳机市场，后有 AirPods 和 HomePod 占领真无线耳机和智能音箱市场。目前，苹果缺的正是一款足够优秀的降噪耳机。
