27C256
DS11001L-page 2
1996 Microchip Technology Inc.
1.0
ELECTRICAL CHARACTERISTICS
1.1
Maximum Ratings*
V
V
programming.......................................-0.6V to +14.0V
Voltage on A9 w.r.t. V
SS
......................-0.6V to +13.5V
Output voltage w.r.t. V
SS
............... -0.6V to V
Storage temperature ..........................-65C to +150C
Ambient temp. with power applied .....-65C to +125C
CC
and input voltages w.r.t. V
voltage w.r.t. V
SS
........-0.6V to +7.25V
PP
SS
during
CC
+1.0V
*Notice: Stresses above those listed under “Maximum Ratings”
may cause permanent damage to the device. This is a stress rat-
ing only and functional operation of the device at those or any
other conditions above those indicated in the operation listings of
this specification is not implied. Exposure to maximum rating con-
ditions for extended periods may affect device reliability.
TABLE 1-1:
PIN FUNCTION TABLE
Name
Function
A0-A14
Address Inputs
CE
Chip Enable
OE
Output Enable
V
PP
Programming Voltage
O0 - O7
Data Output
V
CC
+5V Power Supply
V
SS
Ground
NC
No Connection; No Internal Connec-
tion
NU
Not Used; No External Connection Is
Allowed
TABLE 1-2:
READ OPERATION DC CHARACTERISTICS
V
Commercial:
Industrial:
Extended (Automotive):
CC
= +5V (
±
10%)
Tamb = 0C to +70C
Tamb = -40C to +85C
Tamb = -40
°
C to +125
°
C
Parameter
Part*
Status
Symbol
Min.
Max.
Units
Conditions
Input Voltages
all
Logic "1"
Logic "0"
V
V
IH
IL
2.0
-0.5
V
CC
0.8
+1
V
V
Input Leakage
all
—
I
LI
-10
10
μ
A
V
IN
= 0 to V
CC
Output Voltages
all
Logic "1"
Logic "0"
V
V
OH
OL
2.4
0.45
V
V
I
I
OH
OL
= -400
= 2.1 mA
μ
A
Output Leakage
all
—
I
LO
-10
10
μ
A
V
OUT
= 0V to V
CC
Input Capacitance
all
—
C
IN
—
6
pF
V
f = 1 MHz
IN
= 0V; Tamb = 25
°
C;
Output Capacitance
all
—
C
OUT
—
12
pF
V
f = 1 MHz
OUT
= 0V; Tamb = 25
°
C;
Power Supply Current,
Active
C
I,E
TTL input
TTL input
I
I
CC
1
CC
2
—
—
20
25
mA
mA
V
f = 1 MHz;
OE = CE = V
I
OUT
= 0 mA;
V
IL
= -0.1 to 0.8V;
V
IH
= 2.0 to V
Note 1
CC
= 5.5V; V
PP
= V
CC
IL
;
CC
;
Power Supply Current,
Standby
C
I, E
all
TTL input
TTL input
CMOS input
I
CC
(
S
)
—
2
3
100
mA
mA
μ
A
CE = V
CC
±
0.2V
I
V
PP
PP
Read Current
Read Voltage
all
all
Read Mode
Read Mode
I
PP
V
PP
V
CC
-0.7
100
V
CC
μ
A
V
V
PP
= 5.5V
* Parts: C=Commercial Temperature Range; I, E=Industrial and Extended Temperature Ranges
Note 1: Typical active current increases .75 mA per MHz up to operating frequency for all temperature ranges.