INTEGRATED CIRCUITS
74F244/74F244B
Octal buffers (3-State)
Product specification
IC15 Data Handbook
Philips Semiconductors
1994 Dec 05
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
FEATURES
DESCRIPTION
• 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 ICC (74F244B)
• Reduced loading (74F244B IIL = 40µA)
• Split lead frame offers increased noise immunity (74F244B)
• Industrial temperature range available (-40°C to +85°C) for
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.
74F244
• 74F244 available in SSOP Type II package
TYPE
TYPICAL
PROPAGATION
DELAY
TYPICAL SUPPLY
CURRENT (TOTAL)
74F244
4.0ns
53mA
74F244B
4.0ns
33mA
ORDERING INFORMATION
ORDER CODE
COMMERCIAL RANGE
INDUSTRIAL RANGE
VCC = 5V ±10%,
PKG DWG #
Tamb = 0°C to +70°C
VCC = 5V ±10%,
Tamb = -40°C to +85°C
DESCRIPTION
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
74F (U.L.)
HIGH/LOW
LOAD VALUE
HIGH/LOW
Data inputs (74F244)
1.0/2.67
20µA/1.6mA
Data inputs (74F244B)
1.0/0.067
20µA/40µA
Output enable inputs (active low) (74F244)
1.0/1.67
20µA/1.0mA
PINS
Ian, Ibn
OEa, OEb
Yan, Ybn
DESCRIPTION
Output enable inputs (active low) (74F244B)
1.0/0.067
20µA/40µA
Data outputs
750/106.7
15mA/64mA
NOTE: One (1.0) FAST unit load is defined as: 20µA in the high state and 0.6mA in the low state.
PIN CONFIGURATION
LOGIC SYMBOL
OEa 1
20 VCC
Ia0 2
19 OEb
Yb0 3
18 Ya0
Ia1 4
17 Ib0
Yb1 5
16 Ya1
1
OEa
Ia2 6
15 Ib1
19
OEb
Yb2 7
14 Ya2
Ia3 8
13 Ib2
Yb3 9
12 Ya3
GND 10
11 Ib3
4
6
Ia0
Ia1
Ia2
8
17
Ia3 Ib0
15
13
11
Ib1
Ib2
Ib3
Ya0 Ya1 Ya2 Ya3 Yb0 Yb1 Yb2 Yb3
18
16
14
12
3
5
7
9
VCC = Pin 20
GND = Pin 10
SF00228
SF00227
1994 Dec 5
2
2
853-0357 14381
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
IEC/IEEE SYMBOL
FUNCTION TABLE
INPUTS
1
EN1
19
EN2
2
2D
18
1
4
16
6
14
2
3
15
5
13
7
11
9
SF00229
LOGIC DIAGRAM
Ia0
Ia1
Ia2
Ia3
OEa
2
18
4
16
6
14
8
12
1
Ya0
Ib0
Ya1
Ib1
Ya2
Ib2
Ya3
Ib3
OEb
17
3
15
5
13
7
11
9
Yb0
Yb1
Yb2
Yb3
19
VCC = Pin 20
GND = Pin 10
SF00230
1994 Dec 5
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
12
8
17
OUTPUTS
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
PARAMETER
RATING
UNIT
VCC
Supply voltage
-0.5 to +7.0
V
VIN
Input voltage
-0.5 to +7.0
V
IIN
Input current
-30 to +5
mA
VOUT
Voltage applied to output in high output state
-0.5 to VCC
V
IOUT
Current applied to output in low output state
128
mA
Commercial range
0 to +70
°C
Tamb
O
Operating
ti free
f
air
i temperature
t
t
range
Industrial range
(74F244 only)
-40 to +85
°C
Tstg
Storage temperature range
-65 to +150
°C
RECOMMENDED OPERATING CONDITIONS
LIMITS
SYMBOL
PARAMETER
MIN
NOM
MAX
5.0
5.5
UNIT
VCC
Supply voltage
4.5
VIN
High-level input voltage
2.0
VIL
Low-level input voltage
0.8
V
IIK
Input clamp current
–18
mA
IOH
High-level output current
–15
mA
iol
Low-level output current
64
mA
Tamb
O
Operating
ti free
f
air
i temperature
t
t
range
1994 Dec 5
V
V
Commercial range
0
+70
°C
Industrial range
(74F244 only)
–40
+85
°C
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
High-level output voltage
MIN
TYP2
UNIT
2.5
VIL = MAX,
±5%VCC
2.7
VIH = MIN
±10%VCC
2.0
V
±5%VCC
2.0
V
VCC = MIN,
VIL = MAX,
IOH = -3mA
IOH = -15mA
VOL
Low-level output voltage
VIK
Input clamp voltage
IOL = MAX
VCC = MIN, II = IIK
II
Input current at maximum input voltage
IIH
High-level input current
IIL
Low-level input current
IOZH
Off-state output current,
high-level voltage applied
IOZL
IOS
V
3.4
±10%VCC
V
0.55
V
0.42
0.55
V
-0.73
-1.2
V
VCC = MAX, VI = 7.0V
100
µA
VCC = MAX, VI = 2.7V
20
µA
-1.0
mA
-1.6
mA
-40
µA
VCC = MAX, VO = 2.7V
50
µA
Off-state output current,
low-level voltage applied
VCC = MAX, VO = 0.5V
-50
µA
Short-circuit output current3
VCC = MAX
-225
mA
40
60
mA
60
90
mA
ICCZ
60
90
mA
ICCH
20
30
mA
50
70
mA
29
40
VIH = MIN,
±5%VCC
74F244 OEa, OEb
74F244 Ian, Ibn
VCC = MAX, VI = 0.5V
74F244B all inputs
ICCH
74F244
ICC
MAX
±10%VCC
VCC = MIN,
VOH
LIMITS
TEST
CONDITIONS1
PARAMETER
Supply current (total)
74F244B
ICCL
ICCL
VCC = MAX
VCC = MAX
ICCZ
-100
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 VCC = 5V, Tamb = 25°C.
3. Not more than one output should be shorted at a time. For testing IOS, 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, IOS tests should be performed last.
1994 Dec 5
5
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
AC ELECTRICAL CHARACTERISTICS FOR 74F244
A PORT LIMITS
SYMBOL
PARAMETER
Tamb = +25°C
Tamb = 0°C to +70°C
Tamb = -40°C to +85°C
VCC = +5.0V
CL = 50pF,
RL = 500Ω
VCC = +5.0V ± 10%
CL = 50pF,
RL = 500Ω
VCC = +5.0V ± 10%
CL = 50pF,
RL = 500Ω
TEST
CONDITION
MIN
TYP
MAX
MIN
MAX
MIN
MAX
UNIT
tPLH
tPHL
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
tPZH
tPZL
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
tPHZ
tPLZ
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
Tamb = +25°C
SYMBOL
PARAMETER
TEST
CONDITION
Tamb = 0°C to +70°C
VCC = +5.0V
CL = 50pF, RL = 500Ω
VCC = +5.0V ± 10%
CL = 50pF, RL = 500Ω
UNIT
MIN
TYP
MAX
MIN
MAX
Waveform 1
2.5
2.5
4.5
4.5
5.7
6.0
2.0
2.5
6.2
6.5
ns
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
tPHZ
tPLZ
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
tsk(0)
Output skew1, 2
Waveform 3
2.0
ns
tPLH
tPHL
Propagation delay
Ian, Ibn to Yn
tPZH
tPZL
1.5
NOTES:
1. |tPN actual - tPM 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, VCC, loading, etc.,).
1994 Dec 5
6
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
AC WAVEFORMS
For all waveforms, VM = 1.5V.
Ian, Ibn
VM
Yn, Yn
VM
tPLH
VM
tsk(0)
tPHL
Yn
VM
VM
VM
Yn, Yn
SF00231
SF00232
Waveform 1. Propagation Delay for data to outputs
VM
OEn
Waveform 3. Output skew
VM
tPZH
OEn
VM
tPHZ
tPZL
tPLZ
3.5V
VOH–0.3V
VM
Yn
VM
VM
Yn
VOL+0.3V
0V
SF00233
SF00234
Waveform 2. 3-State output enable time to high level
and output disable time from high level
Waveform 4. 3-State output enable time to low level
and output disable time from low level
TEST CIRCUIT AND WAVEFORMS
SWITCH POSITION
TEST
SWITCH
tPLZ, tPZL
closed
All other
open
7.0V
VCC
tw
90%
NEGATIVE
PULSE
90%
VM
VM
10%
VIN
RL
VOUT
PULSE
GENERATOR
AMP (V)
10%
tTHL (tf )
tTLH (tr )
tTLH (tr )
tTHL (tf )
0V
D.U.T.
RT
CL
RL
Test circuit for 3-State outputs
DEFINITIONS:
RL = Load resistor; see AC electrical characteristics for
value.
CL = Load capacitance includes jig and probe
capacitance; see AC electrical characteristics for
value
RT = Termination resistance should be equal to ZOUT of
pulse generators.
AMP (V)
90%
90%
POSITIVE
PULSE
VM
VM
10%
10%
tw
0V
Input pulse definition
INPUT PULSE REQUIREMENTS
family
74F
amplitude
VM
rep. rate
3.0V
1.5V
1MHz
tw
tTLH
500ns 2.5ns
tTHL
2.5ns
SF000235
1994 Dec 5
7
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
DIP20: plastic dual in-line package; 20 leads (300 mil)
1994 Dec 05
8
SOT146-1
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
SO20: plastic small outline package; 20 leads; body width 7.5 mm
1994 Dec 05
9
SOT163-1
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
SSOP20: plastic shrink small outline package; 20 leads; body width 5.3 mm
1994 Dec 05
10
SOT339-1
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
NOTES
1994 Dec 05
11
Philips Semiconductors
Product specification
Octal buffers (3-State)
74F244/74F244B
DEFINITIONS
Data Sheet Identification
Product Status
Definition
Objective Specification
Formative or in Design
This data sheet contains the design target or goal specifications for product development. Specifications
may change in any manner without notice.
Preliminary Specification
Preproduction Product
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.
Product Specification
Full Production
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 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
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indemnify Philips Semiconductors and Philips Electronics North America Corporation for any damages resulting from such improper use or sale.
Philips Semiconductors
811 East Arques Avenue
P.O. Box 3409
Sunnyvale, California 94088–3409
Telephone 800-234-7381
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)
Document order number:
Date of release: October 28, 1991
9397-750-05103
9397-750-05103