CAT28F102 Datasheet, PDF (13/14 Pages) Catalyst Semiconductor – 1 Megabit CMOS Flash Memory

CAT28F102
Abort/Reset
An Abort/Reset command is available to allow the user
to safely abort an erase or program sequence. Two
consecutive program cycles with XXFFH on the data
bus will abort an erase or a program operation. The
abort/reset operation can interrupt at any time in a
program or erase operation and the device is reset to the
Read Mode.
DATA PROTECTION
1. Power Supply Voltage
When the power supply voltage (VCC) is less than 2.5V,
the device ignores WE signal.
2. Write Inhibit
When CE and OE are terminated to the low level, write
mode is not set.
POWER UP/DOWN PROTECTION
The CAT28F102 offers protection against inadvertent
programming during V_PP and V_CC power transitions.
When powering up the device there is no power-on
sequencing necessary. In other words, V_PP and V_CC
may power up in any order. Additionally V_PP may be
hardwired to V_PPH independent of the state of V_CC and
any power up/down cycling. The internal command
register of the CAT28F102 is reset to the Read Mode on
power up.
POWER SUPPLY DECOUPLING
To reduce the effect of transient power supply voltage
spikes, it is good practice to use a 0.1µF ceramic
capacitor between V_CC and V_SS and V_PP and V_SS. These
high-frequency capacitors should be placed as close as
possible to the device for optimum decoupling.
Figure 10. Alternate A.C. Timing for Program Operation
VCC POWER-UP SETUP PROGRAM LATCH ADDRESS
& STANDBY
COMMAND
& DATA
PROGRAM
VERIFY
PROGRAMMING COMMAND
PROGRAM VCC POWER-DOWN/
VERIFICATION
STANDBY
ADDRESSES
tWC
tWC
tAVEL
tELAX
WE (E)
tWLEL
tEHWH
tWLEL
tEHWH
tWLEL
tEHWH
OE (G)
tGHEL
tEHEL
tEHEH
tEHGL
CE (W)
DATA (I/O)
tDVEH
HIGH-Z
DATA IN
= XX40H
tEHDX
tELEH
tELEH
tEHDX
tDVEH
tDVEH
DATA IN
VCC ^5.0V
0V
VPP ^VPPH
VPPL
tVPEL
DATA IN
= XXC0H
tOE
tEHDX
tOLZ
tLZ
tCE
tRC
tEHQZ
tDF
tOH
VALID
DATA OUT
28F102 F10
13
Doc. No. 25038-0A 2/98 F-1