Philips Semiconductors
74F244/74F244B
Octal buffers (3-State)
Product specification
1994 Dec 05
INTEGRATED CIRCUITS
IC15 Data Handbook
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
2
1994 Dec 5
853-0357 14381
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
= 40
A)
Split lead frame offers increased noise immunity (74F244B)
Industrial temperature range available (-40
C to +85
C) for
74F244
74F244 available in SSOP Type II package
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.
TYPE
TYPICAL
PROPAGATION
DELAY
TYPICAL SUPPLY
CURRENT (TOTAL)
74F244
4.0ns
53mA
74F244B
4.0ns
33mA
ORDERING INFORMATION
ORDER CODE
COMMERCIAL RANGE
INDUSTRIAL RANGE
PKG DWG #
DESCRIPTION
V
CC
= 5V
10%,
V
CC
= 5V
10%,
PKG DWG #
T
amb
= 0
C to +70
C
T
amb
= -40
C to +85
C
20-pin plastic DIP
N74F244N, N74F244BN
I74F244N
SOT146-1
20-pin plastic SOL
N74F244D, N74F244BD
I74F244D
SOT163-1
20-pin plastic SSOP II
N74F244DB
SOT339-1
INPUT AND OUTPUT LOADING AND FAN OUT TABLE
PINS
DESCRIPTION
74F (U.L.)
HIGH/LOW
LOAD VALUE
HIGH/LOW
Ian, Ibn
Data inputs (74F244)
1.0/2.67
20
A/1.6mA
Data inputs (74F244B)
1.0/0.067
20
A/40
A
OEa, OEb
Output enable inputs (active low) (74F244)
1.0/1.67
20
A/1.0mA
Output enable inputs (active low) (74F244B)
1.0/0.067
20
A/40
A
Yan, Ybn
Data outputs
750/106.7
15mA/64mA
NOTE: One (1.0) FAST unit load is defined as: 20
A in the high state and 0.6mA in the low state.
PIN CONFIGURATION
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 VCC
OEa
Ia0
Yb0
Ia1
Yb1
Ia2
Yb2
Ia3
Yb3
GND
SF00227
OEb
Ya0
Ib0
Ya1
Ib1
Ya2
Ib2
Ya3
Ib3
LOGIC SYMBOL
OEa
1
SF00228
2
4
6
8
17
15
13
11
18
16
14
12
3
5
7
9
Ia0
Ia1
Ia2
Ia3
Ib0
Ib1
Ib2
Ib3
Ya0
Ya1 Ya2
Ya3 Yb0 Yb1 Yb2 Yb3
VCC = Pin 20
GND = Pin 10
OEb
19
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 5
3
IEC/IEEE SYMBOL
1
2D
EN1
EN2
1
2
19
2
4
6
8
17
15
13
11
18
16
14
12
3
5
7
9
SF00229
LOGIC DIAGRAM
VCC
=
Pin 20
Ia0
SF00230
OEa
Ia3
Ia2
Ia1
2
4
6
8
1
Ya0
Ya1
Ya2
Ya3
18
16
14
12
Ib0
Ib1
Ib2
Ib3
OEb
17
15
13
11
19
3
5
7
9
Yb0
Yb1
Yb2
Yb3
GND = Pin 10
FUNCTION TABLE
INPUTS
OUTPUTS
OEa
Ia
OEb
Ib
Ya
Yb
L
L
L
L
L
L
L
H
L
H
H
H
H
X
H
X
Z
Z
NOTES:
H = High voltage level
L
= Low voltage level
X = Don't care
Z = High impedance "off" state
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 5
4
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
PARAMETER
RATING
UNIT
V
CC
Supply voltage
-0.5 to +7.0
V
V
IN
Input voltage
-0.5 to +7.0
V
I
IN
Input current
-30 to +5
mA
V
OUT
Voltage applied to output in high output state
-0.5 to V
CC
V
I
OUT
Current applied to output in low output state
128
mA
T
O
ti
f
i t
t
Commercial range
0 to +70
C
T
amb
Operating free air temperature range
Industrial range
(74F244 only)
-40 to +85
C
T
stg
Storage temperature range
-65 to +150
C
RECOMMENDED OPERATING CONDITIONS
SYMBOL
PARAMETER
LIMITS
UNIT
SYMBOL
PARAMETER
MIN
NOM
MAX
UNIT
V
CC
Supply voltage
4.5
5.0
5.5
V
V
IN
High-level input voltage
2.0
V
V
IL
Low-level input voltage
0.8
V
I
IK
Input clamp current
18
mA
I
OH
High-level output current
15
mA
i
ol
Low-level output current
64
mA
T
O
ti
f
i t
t
Commercial range
0
+70
C
T
amb
Operating free air temperature range
Industrial range
(74F244 only)
40
+85
C
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 5
5
DC ELECTRICAL CHARACTERISTICS
(Over recommended operating free-air temperature range unless otherwise noted.)
SYMBOL
PARAMETER
TEST
LIMITS
UNIT
SYMBOL
PARAMETER
CONDITIONS
1
MIN
TYP
2
MAX
UNIT
V
CC
= MIN,
I
OH
= -3mA
10%V
CC
2.5
V
V
OH
High-level output voltage
V
IL
= MAX,
5%V
CC
2.7
3.4
V
V
IH
= MIN
I
OH
= -15mA
10%V
CC
2.0
V
5%V
CC
2.0
V
V
OL
Low-level output voltage
V
CC
= MIN,
V
IL
= MAX,
I
OL
= MAX
10%V
CC
0.55
V
V
IH
= MIN,
5%V
CC
0.42
0.55
V
V
IK
Input clamp voltage
V
CC
= MIN, I
I
= I
IK
-0.73
-1.2
V
I
I
Input current at maximum input voltage
V
CC
= MAX, V
I
= 7.0V
100
A
I
IH
High-level input current
V
CC
= MAX, V
I
= 2.7V
20
A
74F244 OEa, OEb
-1.0
mA
I
IL
Low-level input current
74F244 Ian, Ibn
V
CC
= MAX, V
I
= 0.5V
-1.6
mA
74F244B all inputs
-40
A
I
OZH
Off-state output current,
high-level voltage applied
V
CC
= MAX, V
O
= 2.7V
50
A
I
OZL
Off-state output current,
low-level voltage applied
V
CC
= MAX, V
O
= 0.5V
-50
A
I
OS
Short-circuit output current
3
V
CC
= MAX
-100
-225
mA
I
CCH
40
60
mA
74F244
I
CCL
V
CC
= MAX
60
90
mA
I
CC
Supply current (total)
I
CCZ
60
90
mA
I
CCH
20
30
mA
74F244B
I
CCL
V
CC
= MAX
50
70
mA
I
CCZ
29
40
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.
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 5
6
AC ELECTRICAL CHARACTERISTICS FOR 74F244
A PORT LIMITS
T
amb
= +25
C
T
amb
= 0
C to +70
C
T
amb
= -40
C to +85
C
SYMBOL
PARAMETER
TEST
V
CC
= +5.0V
V
CC
= +5.0V
10%
V
CC
= +5.0V
10%
UNIT
CONDITION
C
L
= 50pF,
R
L
= 500
C
L
= 50pF,
R
L
= 500
C
L
= 50pF,
R
L
= 500
MIN
TYP
MAX
MIN
MAX
MIN
MAX
t
PLH
t
PHL
Propagation delay
Ian, Ibn to Yn
Waveform 1
2.5
2.5
4.0
4.0
5.2
5.2
2.0
2.0
6.2
6.5
1.5
2.0
7.0
7.0
ns
t
PZH
t
PZL
Output enable time
to high or low
Waveform 2
Waveform 4
2.0
2.0
4.3
5.0
5.7
7.0
2.0
2.0
6.7
8.0
2.0
2.0
8.0
8.5
ns
t
PHZ
t
PLZ
Output disable time
from high or low
Waveform 2
Waveform 4
1.5
1.5
2.5
2.5
5.5
5.5
1.0
1.0
6.0
5.5
1.0
1.0
6.0
5.5
ns
AC ELECTRICAL CHARACTERISTICS FOR 74F244B
LIMITS
T
amb
= +25
C
T
amb
= 0
C to +70
C
SYMBOL
PARAMETER
TEST
V
CC
= +5.0V
V
CC
= +5.0V
10%
UNIT
CONDITION
C
L
= 50pF, R
L
= 500
C
L
= 50pF, R
L
= 500
MIN
TYP
MAX
MIN
MAX
t
PLH
t
PHL
Propagation delay
Ian, Ibn to Yn
Waveform 1
2.5
2.5
4.5
4.5
5.7
6.0
2.0
2.5
6.2
6.5
ns
t
PZH
t
PZL
Output enable time
to high or low level
Waveform 2
Waveform 4
2.0
3.0
4.0
5.5
6.0
7.5
2.0
3.0
6.5
8.0
ns
t
PHZ
t
PLZ
Output disable time
from high or low level
Waveform 2
Waveform 4
1.5
1.5
2.5
2.5
5.5
5.5
1.0
1.0
6.0
5.5
ns
t
sk(0)
Output skew
1, 2
Waveform 3
1.5
2.0
ns
NOTES:
1. |t
PN
actual - t
PM
actual| for any output compared to any other output where N and M are either LH or HL.
2. Skew times are valid only under same test conditions (temperature, V
CC
, loading, etc.,).
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 5
7
AC WAVEFORMS
For all waveforms, V
M
= 1.5V.
V
M
V
M
V
M
V
M
Yn
Ian, Ibn
t
PLH
t
PHL
SF00231
Waveform 1. Propagation Delay for data to outputs
V
OH
0.3V
V
M
V
M
V
M
Yn
t
PZH
t
PHZ
SF00233
OEn
0V
Waveform 2. 3-State output enable time to high level
and output disable time from high level
VM
VM
Yn, Yn
tsk
(0)
SF00232
Yn, Yn
Waveform 3. Output skew
V
OL
+0.3V
V
M
V
M
V
M
Yn
t
PZL
t
PLZ
SF00234
OEn
3.5V
Waveform 4. 3-State output enable time to low level
and output disable time from low level
TEST CIRCUIT AND WAVEFORMS
tw
90%
VM
10%
90%
VM
10%
90%
VM
10%
90%
VM
10%
NEGATIVE
PULSE
POSITIVE
PULSE
tw
AMP (V)
0V
0V
tTHL (tf
)
INPUT PULSE REQUIREMENTS
rep. rate
t
w
t
TLH
t
THL
1MHz
500ns 2.5ns
2.5ns
Input pulse definition
VCC
family
74F
D.U.T.
PULSE
GENERATOR
RL
CL
RT
VIN
VOUT
Test circuit for 3-State outputs
DEFINITIONS:
R
L
= Load resistor; see AC electrical characteristics for
value.
C
L
= Load capacitance includes jig and probe
capacitance; see AC electrical characteristics for
value
R
T
= Termination resistance should be equal to Z
OUT
of
pulse generators.
tTHL (tf
)
tTLH (tr
)
tTLH (tr
)
AMP (V)
amplitude
3.0V
1.5V
V
M
RL
7.0V
SWITCH POSITION
TEST
SWITCH
closed
open
All other
t
PLZ
, t
PZL
SF000235
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 05
8
DIP20:
plastic dual in-line package; 20 leads (300 mil)
SOT146-1
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 05
9
SO20:
plastic small outline package; 20 leads; body width 7.5 mm
SOT163-1
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 05
10
SSOP20:
plastic shrink small outline package; 20 leads; body width 5.3 mm
SOT339-1
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
1994 Dec 05
11
NOTES
Philips Semiconductors
Product specification
74F244/74F244B
Octal buffers (3-State)
Philips Semiconductors and Philips Electronics North America Corporation reserve the right to make changes, without notice, in the products,
including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips
Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright,
or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask
work right infringement, unless otherwise specified. Applications that are described herein for any of these products are for illustrative purposes
only. Philips Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing
or modification.
LIFE SUPPORT APPLICATIONS
Philips Semiconductors and Philips Electronics North America Corporation Products are not designed for use in life support appliances, devices,
or systems where malfunction of a Philips Semiconductors and Philips Electronics North America Corporation Product can reasonably be expected
to result in a personal injury. Philips Semiconductors and Philips Electronics North America Corporation customers using or selling Philips
Semiconductors and Philips Electronics North America Corporation Products for use in such applications do so at their own risk and agree to fully
indemnify Philips Semiconductors and Philips Electronics North America Corporation for any damages resulting from such improper use or sale.
This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips
Semiconductors reserves the right to make changes at any time without notice in order to improve design
and supply the best possible product.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 940883409
Telephone 800-234-7381
DEFINITIONS
Data Sheet Identification
Product Status
Definition
Objective Specification
Preliminary Specification
Product Specification
Formative or in Design
Preproduction Product
Full Production
This data sheet contains the design target or goal specifications for product development. Specifications
may change in any manner without notice.
This data sheet contains Final Specifications. Philips Semiconductors reserves the right to make changes
at any time without notice, in order to improve design and supply the best possible product.
Philips Semiconductors and Philips Electronics North America Corporation
register eligible circuits under the Semiconductor Chip Protection Act.
Copyright Philips Electronics North America Corporation 1996
All rights reserved. Printed in U.S.A.
(print code)
Date of release: October 28, 1991
Document order number:
9397-750-05103
9397-750-05103
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