Features

– Single Cycle Reprogram (Erase and Program)

– 2048 Pages (264 Bytes/Page) Main Memory

while Reprogramming the Flash Memory Array

– Ideal for Code Shadowing Applications

– 4 mA Active Read Current Typical

– 2 µA CMOS Standby Current Typical

1.

Description

The AT45DB041B is an SPI compatible serial interface Flash memory ideally suited

for a wide variety of digital voice-, image-, program code- and data-storage applica-

tions. Its 4,325,376 bits of memory are organized as 2048 pages of 264 bytes each. In

addition to the main memory, the AT45DB041B 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 repro-

grammed, as well as reading or writing a continuous data stream. EEPROM emulation

(bit or byte alterability) is easily handled with a self-contained three step Read-Modify-

Write operation. Unlike conventional Flash memories that are accessed randomly with

multiple address lines and a parallel interface, the DataFlash uses a SPI serial inter-

face to sequentially access its data. DataFlash supports SPI mode 0 and mode 3. The

simple serial interface facilitates hardware layout, increases system reliability, mini-

mizes 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. The device operates at clock

frequencies up to 20 MHz with a typical active read current consumption of 4 mA.

To allow for simple in-system reprogrammability, the AT45DB041B does not require

high input voltages for programming. The device operates from a single power supply,

2.5V to 3.6V or 2.7V to 3.6V, for both the program and read operations. The

AT45DB041B 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).

All programming cycles are self-timed, and no separate erase cycle is required before

programming.

4-megabit

2.5-volt or

2.7-volt

AT45DB041B

3443C–DFLSH–5/05