W25Q16DVDAIG-TR Datasheet, PDF (15/80 Pages) Winbond – 3V 16M-BIT SERIAL FLASH MEMORY WITH DUAL AND QUAD SPI

CMP=1, the top 4KB sector will become unprotected while the rest of the array become read-only. Please
refer to the Status Register Memory Protection table for details. The default setting is CMP=0.
7.1.7 Status Register Protect Bits (SRP1, SRP0)
The Status Register Protect bits (SRP1 and SRP0) are non-volatile read/write bits in the status register
(S8 and S7). The SRP bits control the method of write protection: software protection, hardware
protection, power supply lock-down or one time programmable (OTP) protection.
SRP1 SRP0 /WP
Status
Register
Description
0
0
X
Software /WP pin has no control. The Status register can be written to
Protection after a Write Enable instruction, WEL=1. [Factory Default]
0
1
0
Hardware
Protected
When /WP pin is low the Status Register locked and can not
be written to.
0
1
1
Hardware When /WP pin is high the Status register is unlocked and can
Unprotected be written to after a Write Enable instruction, WEL=1.
1
0
X
Power Supply Status Register is protected and can not be written to again
Lock-Down until the next power-down, power-up cycle.⁽¹⁾
1
1
X
One Time Status Register is permanently protected and can not be
Program⁽²⁾ written to.
Notes:
1. When SRP1, SRP0 = (1, 0), a power-down, power-up cycle will change SRP1, SRP0 to (0, 0) state.
2. This feature is available upon special order. Please contact Winbond for details.
7.1.8 Erase/Program Suspend Status (SUS)
The Suspend Status bit is a read only bit in the status register (S15) that is set to 1 after executing a
Erase/Program Suspend (75h) instruction. The SUS status bit is cleared to 0 by Erase/Program Resume
(7Ah) instruction as well as a power-down, power-up cycle.
7.1.9 Security Register Lock Bits (LB3, LB2, LB1)
The Security Register Lock Bits (LB3, LB2, LB1) are non-volatile One Time Program (OTP) bits in Status
Register (S13, S12, S11) that provide the write protect control and status to the Security Registers. The
default state of LB[3:1] is 0, Security Registers are unlocked. LB[3:1] can be set to 1 individually using the
Write Status Register instruction. LB[3:1] are One Time Programmable (OTP), once it’s set to 1, the
corresponding 256-Byte Security Register will become read-only permanently.
7.1.10 Quad Enable Bit (QE)
The Quad Enable (QE) bit is a non-volatile read/write bit in the status register (S9) that allows Quad SPI
operation. When the QE bit is set to a 0 state (factory default), the /WP pin and /HOLD are enabled.
When the QE bit is set to a 1, the Quad IO2 and IO3 pins are enabled, and /WP and /HOLD functions are
disabled.
WARNING: If the /WP or /HOLD pins are tied directly to the power supply or ground during
standard SPI or Dual SPI operation, the QE bit should never be set to a 1.
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Publication Release Date: January 26, 2015
Revision J