S-25C080A H Series

14

3. Write disable (WRDI)

The WRDI instruction is one of ways to reset bit Write Enable Latch (WEL). After selecting the device by the chip select

( CS ), input the instruction code from serial data input (SI).

To reset bit WEL, set the device in the non-select status by CS at the 8th clock of the serial clock. To cancel the WRDI

instruction, input the clock different from a specified value (n = 8 clock) while CS is in “L”. Bit WEL is reset after the

operations shown below.

• The power supply voltage is dropping

• Power-on

• After performing WRDI

• After the completion of Write operation by the WRSR instruction

• After the completion of Write operation by the WRITE instruction

SO

SCK

WP

CS

SI

Instruction

High-Z

12345678

High / Low

Figure 12 WRDI Operation