A278308
Programming and Program Verify
The programming flowchart is shown in Page 10.
The A278308 is shipped with all bits being set to "1".
Programming causes relevant bits to be changed to "0".
The programming mode is started by setting VCC to
+6.25V and VPP to +12.75V, while
CE
and
PGM
are at
V
IL
, and
OE
is at V
IH
. Data to be programmed can be
directly input in the 8 bit format through the data bus.
The write programming algorithm reduces programming
time by using 100µs pulse followed by a byte verification
to determine whether the byte has been successfully
programmed. If the data does not pass the verification,
an additional pulse programming is applied for a
maximum of 25 pulses. On completion of 1 byte
programming and, The verified address is incremented.
After the final address is completed, all bytes are verified
again with VCC = 5.0 Volt.
Program Inhibit
This mode is used to program one of multiple A278308
whose
OE
,
PGM
, VPP, VCC, address bus and data
bus are connected in parallel. When programming is
performed, other A278308 can be inhibited from being
programmed by setting their
CE
pins to V
IH
.
Programming Mode DC Characteristics
(Ta = 0° to 70° VCC = 6.25V
±
0.25V, VPP = 12.75V
±
0.25V)
C
C,
Symbol
V
OH
V
OL
V
IH
V
IL
I
LI
I
CC
I
PP
V
ID
VCC1
VPP1
Parameter
Output High Voltage
Output Low Voltage
Input High Voltage
Input Low Voltage
Input Leakage Current
VCC Current During Program
VPP Current During Program
A9 Auto Select Voltage
Programming Supply Voltage
Programming Voltage
11.5
6.0
12.5
2.0
-0.5
-1
Min.
2.4
0.4
VCC + 0.5
0.8
+1
50
50
12.5
6.5
13
Max.
Unit
V
V
V
V
µA
mA
mA
V
V
V
CE
= V
IL
Test Conditions
I
OH
= -400µA
I
OL
= 2.1mA
VCC = max. Vin = 0V to VCC
A9 = V
ID
Note: VCC must be applied simultaneously or before VPP and removed simultaneously or after VPP.
PRELIMINARY
(December, 1998, Version 2.0)
7
AMIC Technology, Inc.