FM22L16-55-TG Ramtron, FM22L16-55-TG Datasheet - Page 6

• Manufacturer Part Number: FM22L16-55-TG
• Description: F-RAM 4M (256Kx16) 55ns
• Manufacturer: Ramtron

Specifications of FM22L16-55-TG

• Organization: 256 Kbit x 16
• Access Time: 55 ns
• Operating Supply Voltage: 2.7 V to 3.6 V
• Operating Temperature Range: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• Memory Size: 4 Mbit
• Interface: Parallel
• Package / Case: TSOP-44
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

reduced by requiring three more write cycles, one that
requires an exact inversion of the data byte. A flow
chart of the entire write protect operation is shown in
For example, the following sequence write-protects addresses from 0C000h to 13FFFh (sectors 3 & 4):
Rev. 2.0
Apr. 2011
Read
Read
Read
Read
Read
Read
Write 1DAAAh
Write 0ECCCh
Write 0FF00h
Read
Address
12555h
1DAAAh
01333h
0ECCCh
000FFh
1FF00h
00000h
Data
18h
E7h
-
-
-
-
-
-
-
-
Figure 3. Write-Protect State Machine
; Data is don’t care
; return to Normal Operation
; bits 3 & 4 = 1
; complement of 18h
Figure 3. The write-protect settings are nonvolatile.
The factory default: all blocks are unprotected.
FM21L16 - 128Kx16 FRAM
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