AUSTIN SEMICONDUCTOR, INC.
ADVANCE INFORMATION
nvSRAM
AS8nvLC512K32
Austin Semiconductor, Inc.
Mode Selection (continued)
OE\ꢀ13
A15ͲA0ꢀ7
CE\1Ͳ4
WE\1Ͳ4
I/O0Ͳ31
Mode
Power
Activeꢀ8
L
H
L
0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x4B46
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀData
AutoStoreꢀEnable
ActiveꢀICC2ꢀ8
L
H
L
0x4E38
ReadꢀSRAM
OutputꢀData
0xB1C7
0x83E0
0x7C1F
0x703F
0x8FC0
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀHighꢀZ
ReadꢀSRAM
NonvolatileꢀStore
L
H
L
0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x4C63
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
ReadꢀSRAM
Nonvolatileꢀꢀ
Recall
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀData
OutputꢀHighꢀZ
Activeꢀ8
Data Protection
Preventing AutoStore
The AS8nvLC512K32 protects data from corruption during low
voltage conditions by inhibiting all externally initiated
STORE and write operations. The low voltage condition is detected
when VCC < VSWITCH. If the AS8nvLC512K32 is in a write mode
(both CE and WE are LOW) at power up, after a RECALL or STORE,
the write is inhibited until the SRAM is enabled after tLZHSB (HSB
to output active). This protects against inadvertent writes during
power up or brown out conditions.
TheAutoStore function is disabled by initiating anAutoStore disable
sequence. A sequence of read operations is performed in a manner
similar to the software STORE initiation. To initiate the AutoStore
disable sequence, the following sequence of CE controlled read
operations must be performed:
1. Read address 0x4E38 Valid READ
2. Read address 0xB1C7 Valid READ
3. Read address 0x83E0 Valid READ
4. Read address 0x7C1F Valid READ
5. Read address 0x703F Valid READ
6. Read address 0x8B45 AutoStore Disable
The AutoStore is re-enabled by initiating an AutoStore enable
sequence. A sequence of read operations is performed in a manner
similar to the software RECALL initiation. To initiate the AutoStore
enable sequence, the following sequence of CE controlled read
operations must be performed:
1. Read address 0x4E38 Valid READ
2. Read address 0xB1C7 Valid READ
3. Read address 0x83E0 Valid READ
4. Read address 0x7C1F Valid READ
5. Read address 0x703F Valid READ
6. Read address 0x4B46 AutoStore Enable
If the AutoStore function is disabled or re-enabled, a manual STORE
operation (hardware or software) must be issued to save theAutoStore
state through subsequent power down cycles. The part comes from
the factory with AutoStore enabled.
Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.
AS8nvLC512K32
Rev. 0.0 08/09
5
AUSTIN [ AUSTIN SEMICONDUCTOR ]
