A25L20P/A25L10P/A25L05P Series
Read Device Identification (RDID)
The Read Identification (RDID) instruction allows the 8-bit
manufacturer identification code to be read, followed by two
bytes of device identification. The manufacturer identification
is assigned by JEDEC, and has the value 37h, plus the
continuation identification for AMIC Technology. The device
identification is assigned by the device manufacturer, and
indicates the memory in the first bytes (20h), and the memory
capacity of the device in the second byte (22h (Top) or 12h
(Bottom) for A25L20P, 21h(Top) or 11h(Bottom) for A25L10P,
20h(Top) or 10h(Bottom) for A25L05P).
This is followed by the 32-bit device identification, stored in
the memory, being shifted out on Serial Data Output (DO),
each bit being shifted out during the falling edge of Serial
Clock (C).
The instruction sequence is shown in Figure 16. The Read
Identification (RDID) instruction is terminated by driving Chip
S
Select ( ) High at any time during data output.
S
When Chip Select ( ) is driven High, the device is put in the
Stand-by Power mode. Once in the Stand-by Power mode,
the device waits to be selected, so that it can receive, decode
and execute instructions.
Any Read Identification (RDID) instruction while an Erase, or
Program cycle is in progress, is not decoded, and has no
effect on the cycle that is in progress.
S
The device is first selected by driving Chip Select ( ) Low.
Then, the 8-bit instruction code for the instruction is shifted in.
Table 8. Read Identification (READ_ID) Data-Out Sequence
Manufacture Identification
Device Identification
Memory Type Memory Capacity
Continuation ID
Manufacture ID
22h (Top, A25L20PT)
12h (Bottom, A25L20PU)
21h (Top, A25L10PT)
11h (Bottom, A25L10PU)
20h (Top, A25L05PT)
10h (Bottom, A25L05PU)
7Fh
37h
20h
Figure 16. Read Identification (RDID) Data-Out Sequence
S
0
1
2
3
4
5
6
7
8
9
10
13 14 15 16 17 18
21 22 23 24 25 26
29 30 31 32 33 34
37 38 39
C
Instruction
DIO
DO
31
29
26
24 23
21
22
16 15 14 13
10
9
8
7
6
5
2
1
0
18
30
25
17
High Impedance
Continuation ID
Manufacture ID
Memory Type
Memory Capacity
(August, 2007, Version 1.0)
24
AMIC Technology Corp.