AT45DB021B-SI Atmel, AT45DB021B-SI Datasheet - Page 17

• Manufacturer Part Number: AT45DB021B-SI
• Description: IC FLASH 2MBIT 20MHZ 8SOIC
• Manufacturer: Atmel

Specifications of AT45DB021B-SI

• Format - Memory: FLASH
• Memory Type: DataFLASH
• Memory Size: 2M (1024 pages x 264 bytes)
• Speed: 20MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 2.7 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (5.3mm Width), 8-SOP, 8-SOEIAJ
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

10. Write Operations
10.1
10.2
10.3
1937J–DFLSH–9/05
Each transition represents
8 bits and 8 clock cycles
Main Memory Page Program through Buffers
Buffer Write
Buffer to Main Memory Page Program (Data from Buffer Programmed into Flash Page)
CS
SI
CS
SI
CMD
The following block diagram and waveforms illustrate the various write sequences available.
CMD
CS
SI
r r r r r, PA9-7
PAGE PROGRAM
PAGE (256 BYTES)
BUFFER 1 (256 BYTES)
BUFFER 1 TO
BUFFER 1
X
WRITE
PA6-0, BFA8
CMD
X···X, BFA8
r r r r r, PA9-7
BFA7-0
BFA7-0
FLASH MEMORY ARRAY
Starts self-timed erase/program operation
PAGE PROGRAM
THROUGH BUFFER 1
PA6-0, X
I/O INTERFACE
n
THROUGH BUFFER 2
n
PAGE PROGRAM
SI
n+1
· Completes writing into selected buffer
X
n+1
· Completes writing into selected buffer
· Starts self-timed erase/program operation
BUFFER 2 (256 BYTES)
Last Byte
Last Byte
AT45DB021B
n = 1st byte read
n+1 = 2nd byte read
BUFFER 2 TO
PAGE PROGRAM
BUFFER 2
WRITE
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