CY14C256PA_12 Datasheet, PDF (20/43 Pages) Cypress Semiconductor – 256-Kbit (32 K × 8) SPI nvSRAM with Real Time Clock

CY14C256PA
CY14B256PA
CY14E256PA
Device ID
Device ID is a 4-byte read only code identifying a type of product uniquely. This includes the product family code, configuration, and
density of the product.
Table 7. Device ID
Device
CY14C256PA
CY14B256PA
CY14E256PA
Device ID
(4 bytes)
0x0681C090
0x0681C890
0x0681D090
31–21
(11 bits)
Manufacturer ID
00000110100
00000110100
00000110100
Device ID Description
20–7
(14 bits)
Product ID
00001110000001
00001110010001
00001110100001
6–3
(4 bits)
Density ID
0010
0010
0010
2–0
(3 bits)
Die Rev
000
000
000
The device ID is divided into four parts as shown in Table 9:
1. Manufacturer ID (11 bits)
This is the JEDEC assigned manufacturer ID for Cypress.
JEDEC assigns the manufacturer ID in different banks. The first
three bits of the manufacturer ID represent the bank in which ID
is assigned. The next eight bits represent the manufacturer ID.
Cypress’s manufacturer ID is 0x34 in bank 0. Therefore the
manufacturer ID for all Cypress nvSRAM products is:
Cypress ID - 000_0011_0100
2. Product ID (14 bits)
The product ID for device is shown in the Table 9.
3. Density ID (4 bits)
The 4 bit density ID is used as shown in Table 9 for indicating the
256 Kb density of the product.
4. Die Rev (3 bits)
This is used to represent any major change in the design of the
product. The initial setting of this is always 0x0.
RDID (Device ID Read) Instruction
This instruction is used to read the JEDEC assigned
manufacturer ID and product ID of the device at SPI frequency
upto 40 MHz. This instruction can be used to identify a device on
the bus. RDID instruction can be issued by shifting the op-code
for RDID in through the SI pin of nvSRAM after CS goes LOW.
This is followed by nvSRAM shifting out the four bytes of device
ID through the SO pin.
Figure 27. RDID Instruction
CS
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
SCK
Op-Code
SI
1001111 1
Byte - 4
Byte - 3
Byte - 2
Byte - 1
SO
HI-Z
D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0
MSB
LSB
4-Byte Device ID
Document Number: 001-65281 Rev. *E
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