FM22LD16_09 RAMTRON [Ramtron International Corporation], FM22LD16_09 Datasheet - Page 6

Manufacturer Part Number

FM22LD16_09

Description

4Mbit F-RAM Memory

Manufacturer

RAMTRON [Ramtron International Corporation]

Datasheet

1.FM22LD16_09.pdf (14 pages)

For example, the following sequence write-protects addresses from 18000h to 27FFFh (sectors 3 & 4):

Rev. 2.0

Dec. 2009

Read

Write 3AAAAh

Write 1CCCCh

Write 0FF00h

Read

Address

24555h

3AAAAh

02333h

1CCCCh

000FFh

3EF00h

00000h

Data

18h

E7h

Figure 2. Write-Protect State Machine

; bits 3 & 4 = 1

; complement of 18h

; Data is don’t care

; return to Normal Operation

FM22LD16 - 256Kx16 FRAM

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