CAT28C64BLI12 ON Semiconductor, CAT28C64BLI12 Datasheet - Page 11

• Manufacturer Part Number: CAT28C64BLI12
• Description: IC EEPROM 64KBIT 120NS 28DIP
• Manufacturer: ON Semiconductor

Specifications of CAT28C64BLI12

• Format - Memory: EEPROMs - Parallel
• Memory Type: EEPROM
• Memory Size: 64K (8K x 8)
• Speed: 120ns
• Interface: Parallel
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 28C64BLI-12; CAT28C64BLI-12; CAT28C64BLI-12

To activate the software data protection, the device must
be sent three write commands to specific addresses with
specific data (Figure 9). This sequence of commands
(along with subsequent writes) must adhere to the page
write timing specifications (Figure 11). Once this is done,
all subsequent byte or page writes to the device must be
preceded by this same set of write commands. The data
protection mechanism is activated until a deactivate
sequence is issued regardless of power on/off transitions.
This gives the user added inadvertent write protection
on power-up in addition to the hardware protection
provided.
Figure 11. Software Data Protection Timing
Figure 12. Resetting Software Data Protection Timing
© 2009 SCILLC. All rights reserved.
Characteristics subject to change without notice
WE
DATA
ADDRESS
CE
DATA
ADDRESS
CE
WE
1555
AA
0AAA
55
1555
AA
1555
80
0AAA
55
11
1555
AA
To allow the user the ability to program the device with
an EEPROM programmer (or for testing purposes) there
is a software command sequence for deactivating the
data protection. The six step algorithm (Figure 10) will
reset the internal protection circuitry, and the device will
return to standard operating mode (Figure 12 provides
reset timing). After the sixth byte of this reset sequence
has been issued, standard byte or page writing can
commence.
1555
t WP
A0
0AAA
55
t BLC
ENABLED
1555
BYTE OR
WRITES
20
PAGE
t WC
Speed
90: 90ns
12: 120ns
15: 150ns
t WC
SDP
RESET
DEVICE
UNPROTECTED
Doc. No. MD-1011, Rev. I
CAT28C64B