25C040-E/SN Microchip Technology, 25C040-E/SN Datasheet - Page 11

• Manufacturer Part Number: 25C040-E/SN
• Description: IC EEPROM 4KBIT 3MHZ 8SOIC
• Manufacturer: Microchip Technology

Specifications of 25C040-E/SN

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 4K (512 x 8)
• Speed: 3MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.7
The following protection has been implemented to
prevent inadvertent writes to the array:
• The write enable latch is reset on power-up
• A write enable instruction must be issued to set
• After a byte write, page write or STATUS register
• CS must be set high after the proper number of
• Access to the array during an internal write cycle
• The write enable latch is reset when the WP pin is
TABLE 3-3:
© 2006 Microchip Technology Inc.
the write enable latch
write, the write enable latch is reset
clock cycles to start an internal write cycle
is ignored and programming is continued
low
High
High
Low
WP
Data Protection
WRITE-PROTECT FUNCTIONALITY MATRIX
WEL
X
0
1
Protected Blocks
Protected
Protected
Protected
25AA040/25LC040/25C040
Unprotected Blocks
3.8
The 25XX040 powers on in the following state:
• The device is in low-power Standby mode
• The write enable latch is reset
• SO is in high-impedance state
• A low level on CS is required to enter active state
(CS = 1)
Protected
Protected
Writable
Power-On State
STATUS Register
Protected
Protected
Writable
DS21204E-page 11