AUSTIN SEMICONDUCTOR, INC.

nvSRAM

nvSRAM

nvSRAM

nvSRAM

nvSRAM

AS8nvC512K32

AS8nvC512K32

Rev. 0.0 08/09

Austin Semiconductor, Inc. reserves the right to change products or specifications without notice.

5

Austin Semiconductor, Inc.

ADVANCE INFORMATION

Mode Selection (continued)

Preventing AutoStore

The AutoStore function is disabled by initiating an AutoStore 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 the AutoStore

state through subsequent power down cycles. The part comes from

the factory with AutoStore enabled.

Data Protection

The AS8nvC512K32 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 AS8nvC512K32 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.

OE\

13

A15 A0

7

Mode

Power

L

H

L

0x4E38

Read SRAM

Output Data

Active

8

0xB1C7

Read SRAM

Output Data

0x83E0

Read SRAM

Output Data

0x7C1F

Read SRAM

Output Data

0x703F

Read SRAM

Output Data

0x4B46

AutoStore Enable

Output Data

L

H

L

0x4E38

Read SRAM

Output Data

8

0xB1C7

Read SRAM

Output Data

0x83E0

Read SRAM

Output Data

0x7C1F

Read SRAM

Output Data

0x703F

Read SRAM

Output Data

0x8FC0

Nonvolatile Store

Output High Z

L

H

L

0x4E38

Read SRAM

Output Data

Active

8

0xB1C7

Read SRAM

Output Data

0x83E0

Read SRAM

Output Data

0x7C1F

Read SRAM

Output Data

0x703F

Read SRAM

Output Data

0x4C63

Nonvolatile

Output High Z

Recall