4-megabit
3.0-volt Only or
2.7-volt Only
Serial Firmware
DataFlash
®
AT26DF041
3495B–DFLSH–8/05
Features
• Single 3.0V - 3.6V or 2.7V - 3.6V Supply
Serial Peripheral Interface (SPI) Compatible
33 MHz Max Clock Frequency
Byte Program Operation
Page Program Operation
– 2048 Pages (256 Bytes/Page) Main Memory
– Single Cycle Reprogram Capability (Page Erase and Program)
Supports Optional Page and Block (2 KB or 4 KB) Erase Operations
Continuous Read Capability through Entire Array
– Ideal for Code Shadowing Applications
Hardware Data Protection Feature for the Top 64 KB of Memory
Low Power Dissipation
– 4 mA Active Read Current Typical
– 2 µA CMOS Standby Current Typical
5.0V-tolerant Inputs: SI, SCK, CS, and WP Pins
100,000 Program/Erase Cycles Typical
Data Retention – 20 years
1. Description
The AT26DF041 is a 3.0-volt or 2.7-volt only, serial interface Flash memory ideally
suited for a wide variety of program code- and data-storage applications. Its 4,194,304
bits of memory are organized as 2048 pages of 256 bytes each. Unlike conventional
Flash memories that are accessed randomly with multiple address lines and a parallel
interface, the DataFlash
®
uses an SPI serial interface to sequentially access its data.
The DataFlash supports SPI mode 0 and mode 3. The simple serial interface facili-
tates hardware layout, increases system reliability, minimizes switching noise, and
reduces package size and active pin count. The device is optimized for use in many
commercial and industrial applications where high density, low pin count, low voltage,
and low power are essential. To allow for simple in-system reprogrammability, the
AT26DF041 does not require high input voltages for programming. The device oper-
ates from a single power supply, 3.0V to 3.6V or 2.7V to 3.6V, for both the program
and read operations. The AT26DF041 is enabled through the chip select pin (CS) and
accessed via a three-wire interface consisting of the Serial Input (SI), Serial Output
(SO), and the Serial Clock (SCK).
Table 1-1. Pin Configurations
Pin Name Function
CS Chip Select
SCK Serial Clock
SI Serial Input
SO Serial Output
WP
Hardware Write
Protect Pin
8-SOIC
1
2
3
4
8
7
6
5
CS
SO
WP
GND
VCC
NC
SCK
SI
8-MLF Top View
1
2
3
4
8
7
6
5
CS
SO
WP
GND
VCC
NC
SCK
SI