AT45D021 Datasheet, PDF (1/18 Pages) ATMEL Corporation – 2-Megabit 5-volt Only Serial DataFlash

Features
• Single 4.5V - 5.5V 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 Nonvolatile Memory
• Internal Program and Control Timer
• Fast Page Program Time – 7 ms Typical
• 80 µs Typical Page to Buffer Transfer Time
• Low Power Dissipation
– 15 mA Active Read Current Typical
– 15 µA CMOS Standby Current Typical
• 10 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 AT45D021 is a 5-volt only, serial interface Flash memory suitable for in-system
reprogramming. Its 2,162,688 bits of memory are organized as 1024 pages of 264-
bytes each. In addition to the main memory, the AT45D021 also contains two data
SRAM buffers of 264-bytes each. The buffers allow receiving of data while a page in
the main memory is being reprogrammed. Unlike conventional Flash memories 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
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Pin Configurations
PLCC
Pin Name
CS
SCK
SI
SO
WP
RESET
RDY/BUSY
Function
Chip Select
Serial Clock
Serial Input
Serial Output
Harware Page Write
Protect Pin
Chip Reset
Ready/Busy
RDY/BUSY 1
RESET 2
WP 3
NC 4
NC 5
VCC 6
GND 7
NC 8
NC 9
NC 10
CS 11
SCK 12
SI 13
SO 14
TSOP Top View
Type 1
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.
PLCC
28 NC
27 NC
26 NC
25 NC
24 NC
23 NC
22 NC
21 NC
20 NC
19 NC
18 NC
17 NC
16 NC
15 NC
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
5-volt Only
Serial
DataFlash^®
AT45D021
Rev. 0869B–07/98
1