W25Q64BV Datasheet, PDF (45/61 Pages) Winbond – 64M-BIT SERIAL FLASH MEMORY WITH DUAL AND QUAD SPI

W25Q64BV
11.2.27 Read Unique ID Number (4Bh)⁽¹⁾
The Read Unique ID Number instruction accesses a factory-set read-only 64-bit number that is unique to
each W25Q64BV device. The ID number can be used in conjunction with user software methods to help
prevent copying or cloning of a system. The Read Unique ID instruction is initiated by driving the /CS pin
low and shifting the instruction code “4Bh” followed by a four bytes of dummy clocks. After which, the 64-
bit ID is shifted out on the falling edge of CLK as shown in figure 28.
DO
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 101 102 103
DO
*
63 62 61 60 59 2 1 0
*=MSB
Note:
Figure 28. Read Unique ID Number Instruction Sequence
1. For W25Q64BV, this feature is available upon special request. Please contact Winbond for details.
- 45 -
Publication Release Date: July 08, 2010
Revision E