Cypress CY14B104LA, Техническое описание

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PRELIMINARY
CY14B104LA, CY14B104NA
Document #: 001-49918 Rev. *A Page 6 of 23
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 CY14B104LA/CY14B104NA protects data from corruption
during low voltage conditions by inhibiting all externally initiated
STORE and write operations. The low voltage condition is
detected when V
CC
< V
SWITCH
. If the
CY14B104LA/CY14B104NA 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 t
LZHSB
(HSB to output
active). This protects against inadvertent writes during power up
or brown out conditions.
Noise Considerations
Refer to CY application note AN1064 .
L H L 0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x4B46
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
AutoStore Enable
Output Data
Output Data
Output Data
Output Data
Output Data
Output Data Active
[8]
L H L 0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x8FC0
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Nonvolatile Store
Output Data
Output Data
Output Data
Output Data
Output Data
Output High Z
Active I
CC2
[8]
L H L 0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x4C63
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Nonvolatile
Recall
Output Data
Output Data
Output Data
Output Data
Output Data
Output High Z
Active
[8]
Table 1. Mode Selection (continued)
CE WE OE, BHE, BLE
[3]
A
15
- A
0
[7]
Mode I/O Power
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