AT45DB021 Datasheet, PDF (1/18 Pages) ATMEL Corporation – 2-Megabit 2.7-volt Only Serial DataFlash

Features
• Single 2.7V - 3.6V Supply
• Serial Interface Architecture
• Page Program Operation
– Single Cycle Reprogram (Erase and Program)
– 1024 Pages (264 Bytes/Page) Main Memory
• Two 264-Byte SRAM Data Buffers – Allows Receiving of Data
while Reprogramming of Non-Volatile Memory
• Internal Program and Control Timer
• Fast Page Program Time – 7 ms Typical
• 120 µs Typical Page to Buffer Transfer Time
• Low Power Dissipation
– 4 mA Active Read Current Typical
– 5 µA CMOS Standby Current Typical
• 5 MHz Max Clock Frequency
• Hardware Data Protection Feature
• Serial Peripheral Interface (SPI) Compatible – Modes 0 and 3
• CMOS and TTL Compatible Inputs and Outputs
• Commercial and Industrial Temperature Ranges
Description
The AT45DB021 is a 2.7-volt only, serial interface Flash memory suitable for in-sys-
tem reprogramming. Its 2,162,688 bits of memory are organized as 1024 pages of
264-bytes each. In addition to the main memory, the AT45DB021 also contains two
SRAM data buffers of 264-bytes each. The buffers allow receiving of data while a
page in the main memory is being reprogrammed. Unlike conventional Flash memo-
ries that are accessed randomly with multiple address lines and a parallel interface,
the DataFlash uses a serial interface to sequentially access its data. The simple serial
interface facilitates hardware layout, increases system reliability, minimizes switching
Pin Configurations
(continued)
PLCC
Pin Name Function
CS
SCK
SI
SO
WP
RESET
RDY/BUSY
Chip Select
Serial Clock
Serial Input
Serial Output
Hardware Page Write
Protect Pin
Chip Reset
Ready/Busy
SCK 5
SI 6
SO 7
NC 8
NC 9
NC 10
NC 11
NC 12
NC 13
29 WP
28 RESET
27 RDY/BUSY
26 NC
25 NC
24 NC
23 NC
22 NC
21 NC
Note: PLCC package pins 16
and 17 are DON’T CONNECT.
RDY/BUSY
1
RESET
2
WP
3
NC
4
NC
5
NC
6
VCC
7
GND
8
NC
9
NC
10
NC
11
NC
12
CS
13
SCK
14
SI
15
SO
16
TSOP Top View
Type 1
32
NC
31
NC
30
NC
29
NC
28
NC
27
NC
26
NC
25
NC
24
NC
23
NC
22
NC
21
NC
20
NC
19
NC
18
NC
17
NC
SOIC
GND
1
NC
2
NC
3
CS
4
SCK
5
SI
6
SO
7
NC
8
NC
9
NC
10
NC
11
NC
12
NC
13
NC
14
28
VCC
27
NC
26
NC
25
WP
24
RESET
23
RDY/BUSY
22
NC
21
NC
20
NC
19
NC
18
NC
17
NC
16
NC
15
NC
2-Megabit
2.7-volt Only
Serial
DataFlash^®
AT45DB021
Rev. 0868B–07/98
1