INTEGRATED CIRCUITS
74F244/74F244B
Octal buffers (3-State)
Product specification
IC15 Data Handbook
1994 Dec 05
Philips Semiconductors
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
FEATURES
•
Octal bus interface
•
3-State output buffer sink 64mA
•
15mA source current
•
Guaranteed output skew less than 2.0ns (74F244B)
•
Reduced ground bounce (74F244B)
•
Reduced I
CC
(74F244B)
•
Reduced loading (74F244B I
IL
= 40µA)
•
Split lead frame offers increased noise immunity (74F244B)
•
Industrial temperature range available (-40°C to +85°C) for
74F244
DESCRIPTION
The 74F244 is an octal buffer that is ideal for driving bus lines of
buffer memory address registers. The outputs are all capable of
sinking 64mA and sourcing up to 15mA, producing very good
capacitive drive characteristics. The device features two output
enables, OEa and OEb, each controlling four of the 3-State outputs.
The 74F244B is functionally equivalent to the 74F244. It has been
designed to reduce effects of ground noise. Other advantages are
noted in the features.
TYPICAL
PROPAGATION
DELAY
4.0ns
4.0ns
TYPE
74F244
74F244B
TYPICAL SUPPLY
CURRENT (TOTAL)
53mA
33mA
•
74F244 available in SSOP Type II package
ORDERING INFORMATION
ORDER CODE
COMMERCIAL RANGE
DESCRIPTION
T
amb
= 0
°
C to +70
°
C
20-pin plastic DIP
20-pin plastic SOL
20-pin plastic SSOP II
N74F244N, N74F244BN
N74F244D, N74F244BD
N74F244DB
V
CC
= 5V
±
10%,
INDUSTRIAL RANGE
T
amb
= -40
°
C to +85
°
C
I74F244N
I74F244D
V
CC
= 5V
±
10%,
PKG DWG #
SOT146-1
SOT163-1
SOT339-1
INPUT AND OUTPUT LOADING AND FAN OUT TABLE
PINS
Ian, Ibn
Data inputs (74F244)
Data inputs (74F244B)
OEa, OEb
Output enable inputs (active low) (74F244)
Output enable inputs (active low) (74F244B)
Yan, Ybn
Data outputs
NOTE:
One (1.0) FAST unit load is defined as: 20µA in the high state and 0.6mA in the low state.
DESCRIPTION
74F (U.L.)
HIGH/LOW
1.0/2.67
1.0/0.067
1.0/1.67
1.0/0.067
750/106.7
LOAD VALUE
HIGH/LOW
20µA/1.6mA
20µA/40µA
20µA/1.0mA
20µA/40µA
15mA/64mA
PIN CONFIGURATION
OEa 1
Ia0 2
Yb0 3
Ia1 4
Yb1 5
Ia2 6
Yb2 7
Ia3 8
Yb3 9
GND 10
20 V
CC
19 OEb
18 Ya0
17 Ib0
16 Ya1
15 Ib1
14 Ya2
13 Ib2
12 Ya3
11 Ib3
LOGIC SYMBOL
2
4
6
8
17
15
13
11
Ia0
1
19
OEa
OEb
Ia1
Ia2
Ia3 Ib0
Ib1
Ib2
Ib3
Ya0 Ya1 Ya2 Ya3 Yb0 Yb1 Yb2 Yb3
18
V
CC
= Pin 20
GND = Pin 10
16
14
12
3
5
7
9
SF00227
SF00228
1994 Dec 5
2
853-0357 14381
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
IEC/IEEE SYMBOL
1
19
EN1
EN2
FUNCTION TABLE
INPUTS
OEa
L
Ia
L
H
X
OEb
L
L
H
Ib
L
H
X
OUTPUTS
Ya
L
H
Z
Yb
L
H
Z
2
4
6
8
17
15
13
11
2D
1
18
16
14
12
L
H
2
3
5
7
9
NOTES:
H = High voltage level
L = Low voltage level
X = Don’t care
Z = High impedance ”off” state
SF00229
LOGIC DIAGRAM
Ia0
2
18
Ya0
Ib0
17
3
Yb0
Ia1
4
16
Ya1
Ib1
15
5
Yb1
Ia2
6
14
Ya2
Ib2
13
7
Yb2
Ia3
8
12
Ya3
Ib3
11
9
Yb3
OEa
1
OEb
19
V
CC
= Pin 20
GND = Pin 10
SF00230
1994 Dec 5
3
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
ABSOLUTE MAXIMUM RATINGS
(Operation
beyond the limit set forth in this table may impair the useful life of the device. Unless otherwise noted these limits are over the
operating free air temperature range.)
SYMBOL
V
CC
V
IN
I
IN
V
OUT
I
OUT
Supply voltage
Input voltage
Input current
Voltage applied to output in high output state
Current applied to output in low output state
Commercial range
T
amb
T
stg
Operating f
O
ti free air t
i temperature range
t
Storage temperature range
Industrial range
(74F244 only)
PARAMETER
RATING
-0.5 to +7.0
-0.5 to +7.0
-30 to +5
-0.5 to V
CC
128
0 to +70
-40 to +85
-65 to +150
UNIT
V
V
mA
V
mA
°
C
°
C
°
C
RECOMMENDED OPERATING CONDITIONS
LIMITS
SYMBOL
V
CC
V
IN
V
IL
I
IK
I
OH
i
ol
T
amb
Supply voltage
High-level input voltage
Low-level input voltage
Input clamp current
High-level output current
Low-level output current
Commercial range
Operating f
O
ti free air t
i temperature range
t
Industrial range
(74F244 only)
0
–40
PARAMETER
MIN
4.5
2.0
0.8
–18
–15
64
+70
+85
NOM
5.0
MAX
5.5
UNIT
V
V
V
mA
mA
mA
°
C
°
C
1994 Dec 5
4
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
DC ELECTRICAL CHARACTERISTICS
(Over recommended operating free-air temperature range unless otherwise noted.)
SYMBOL
PARAMETER
V
CC
= MIN,
V
OH
High-level output voltage
V
IL
= MAX,
V
IH
= MIN
I
OH
= -15mA
TEST
CONDITIONS
1
I
OH
= -3mA
±10%V
CC
±5%V
CC
±10%V
CC
±5%V
CC
V
OL
Low-level output voltage
V
CC
= MIN,
V
IL
= MAX,
V
IH
= MIN,
V
IK
I
I
I
IH
I
IL
Input clamp voltage
Input current at maximum input voltage
High-level input current
74F244 OEa, OEb
Low-level input current
74F244 Ian, Ibn
74F244B all inputs
I
OZH
I
OZL
I
OS
Off-state output current,
high-level voltage applied
Off-state output current,
low-level voltage applied
Short-circuit output current
3
I
CCH
74F244
I
CC
Supply current (total)
I
CCL
I
CCZ
I
CCH
74F244B
I
CCL
I
CCZ
V
CC
= MAX
V
CC
= MAX
V
CC
= MAX, V
O
= 2.7V
V
CC
= MAX, V
O
= 0.5V
V
CC
= MAX
-100
40
60
60
20
50
29
V
CC
= MAX, V
I
= 0.5V
V
CC
= MIN, I
I
= I
IK
V
CC
= MAX, V
I
= 7.0V
V
CC
= MAX, V
I
= 2.7V
I
OL
= MAX
±10%V
CC
±5%V
CC
0.42
-0.73
LIMITS
MIN
2.5
2.7
2.0
2.0
0.55
0.55
-1.2
100
20
-1.0
-1.6
-40
50
-50
-225
60
90
90
30
70
40
3.4
TYP
2
MAX
UNIT
V
V
V
V
V
V
V
µA
µA
mA
mA
µA
µA
µA
mA
mA
mA
mA
mA
mA
mA
NOTES:
1. For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions for the applicable type.
2. All typical values are at V
CC
= 5V, T
amb
= 25
°
C.
3. Not more than one output should be shorted at a time. For testing I
OS
, the use of high-speed test apparatus and/or sample-and-hold
techniques are preferable in order to minimize internal heating and more accurately reflect operational values. Otherwise, prolonged shorting
of a high output may raise the chip temperature well above normal and thereby cause invalid readings in other parameter tests. In any
sequence of parameter tests, I
OS
tests should be performed last.
1994 Dec 5
5
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