at45db021d-ssh-sl955 ATMEL Corporation, at45db021d-ssh-sl955 Datasheet - Page 26

• Manufacturer Part Number: at45db021d-ssh-sl955
• Description: 2-megabit 2.7-volt Minimum Dataflash
• Manufacturer: ATMEL Corporation

14.1
14.1.1
14.1.2
14.1.3
14.1.4
26
Value
Value
Value
Value
Hex
1FH
Hex
23H
Hex
00H
Hex
00H
Manufacturer and Device ID Information
CS
SO
Bit 7
Bit 7
Bit 7
Bit 7
AT45DB021D
SI
Byte 1 – Manufacturer ID
Byte 2 – Device ID (Part 1)
Byte 3 – Device ID (Part 2)
Byte 4 – Extended Device Information String Length
0
0
0
0
Family Code
MLC Code
Each transition
represents 8 bits
Bit 6
Bit 6
Bit 6
Bit 6
0
0
0
0
Bit 5
Bit 5
Bit 5
Bit 5
0
1
0
0
Opcode
To read the identification information, the CS pin must first be asserted and the opcode of 9FH
must be clocked into the device. After the opcode has been clocked in, the device will begin out-
putting the identification data on the SO pin during the subsequent clock cycles. The first byte
that will be output will be the Manufacturer ID followed by two bytes of Device ID information.
The fourth byte output will be the Extended Device Information String Length, which will be 00H
indicating that no Extended Device Information follows. As indicated in the JEDEC standard,
reading the Extended Device Information String Length and any subsequent data is optional.
Deasserting the CS pin will terminate the Manufacturer and Device ID Read operation and put
the SO pin into a high-impedance state. The CS pin can be deasserted at any time and does not
require that a full byte of data be read.
JEDEC Assigned Code
9FH
Bit 4
Bit 4
Bit 4
Bit 4
Byte Count
1
0
0
0
Manufacturer ID
Byte n
Product Version Code
1FH
Bit 3
Bit 3
Bit 3
Bit 3
1
0
0
0
Density Code
Bit 2
Bit 2
Bit 2
Bit 2
1
0
0
0
Device ID
Byte 1
23H
Bit 1
Bit 1
Bit 1
Bit 1
1
1
0
0
Bit 0
Bit 0
Bit 0
Bit 0
Device ID
1
1
0
0
Byte 2
00H
String Length
Information
Extended
Device
Manufacturer ID
Family Code
Density Code
MLC Code
Product Version
Byte Count
00H
if the Extended Device Information String Length
This information would only be output
value was something other than 00H.
Information
Extended
Device
Byte x
Data
1FH = Atmel
00011 = 2-Mbit
00000 = Initial Version
00H = 0 Bytes of Information
Information
Byte x + 1
Extended
Device
001 = DataFlash
000 = 1-bit/Cell Technology
Data
3638F–DFLASH–4/08