25LC256-H/SN Microchip Technology, 25LC256-H/SN Datasheet - Page 11

• Manufacturer Part Number: 25LC256-H/SN
• Description: 256K, 32K X 8, 2.5V SER EE 150C 8 SOIC 3.90mm (.150") TUBE
• Manufacturer: Microchip Technology

Specifications of 25LC256-H/SN

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 256K (32K x 8)
• Speed: 5MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 2.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 150°C
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

3.4
The 25LCXXX contains a write enable latch.
Table 5-1 for the write-protect functionality matrix. This
latch must be set before any write operation will be com-
pleted internally. The WREN instruction will set the latch,
and the WRDI will reset the latch.
FIGURE 3-4:
FIGURE 3-5:
© 2009 Microchip Technology Inc.
Write Enable (WREN) and Write
Disable (WRDI)
WRITE ENABLE SEQUENCE (WREN)
WRITE DISABLE SEQUENCE (WRDI)
SCK
CS
SO
SCK
SI
CS
SO
SI
0
0
0
0
0
1
0
1
See
Preliminary
High-Impedance
0
High-Impedance
0
2
2
0
0
3
3
The following is a list of conditions under which the
write enable latch will be reset:
• Power-up
• WRDI instruction successfully executed
• WRSR instruction successfully executed
• WRITE instruction successfully executed
0
0
4
4
1
5
1
5
1
6
1 0
6
0
7
0
7
25LCXXX
DS22131C-page 11