I am currently evaluating the AT25SF641B-SHB-T device as replacement for other SPI flash device. I found that timing for chip erase operation (command 0xC7) is much much faster than specified by datasheet ( DS-AT25SF641B-191D-122020.pdf )
The datasheet states on page 51 a typical chip erase time of 30 seconds. I measure about 1220 ms here. (operating the device at room temp, 3.3V) Is the datasheet wrong here? Or am I overlooking something? Timings for other operations seem in line with datasheet. (64K erase=~219ms, 32K erase=~119ms, sector erase=~31ms)
Please try programming a large percentage of your flash chip and then running the erase routine and you will see the erase time extend. Lite Blue