Fairchild MM74HC244 service manual
MM74HC244
Octal 3-STATE Buffer
MM74HC244 Octal 3-STATE Buffer
September 1983
Revised May 2005
General Description
The MM74HC244 is a non-inverting buffer and has two
active low enables (1G and 2G); each enable independently controls 4 buffers. This device does not have
Schmitt trigger inputs.
These 3-STATE buffers utilize advanced silicon-gate
CMOS technology and are general purpose high speed
non-inverting buffers. The y possess h igh drive cur rent ou tputs which enable high spee d op eration even when driv ing
large bus capacitances. These circuits achieve speeds
comparable to low power Schottky devices, while retaining
the advantage of CMOS circuit ry, i.e., high noise immunity,
and low power consumption. All three devices have a
fanout of 15 LS-TTL equivalent inputs.
All inputs are protected from damage due to static discharge by diodes to V
and ground.
CC
Features
■ Typical propagation delay: 14 ns
■ 3-STATE outputs for connection to system buses
■ Wide power supply range: 2–6V
■ Low quiescent supply current: 80
■ Output current: 6 mA
P
A
Ordering Code:
Order Number Package Number Package Description
MM74HC244WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300" Wide
MM74HC244SJ M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
MM74HC244MTC MTC20 20-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide
MM74HC244N N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300" Wide
Devices also availab l e in Tape and Reel. Specify by appending the suffix let t er “X” to the ordering code.
Connection Diagram
Truth Table
1G 1A 1Y 2G 2A 2Y
LLLLLL
LHHLHH
HLZHLZ
H HIGH Level
L
Z
HHZHHZ
LOW Level
High Impedance
Top View
© 2005 Fairchild Semiconductor Corporation DS005327 www.fairchildsemi.com
Logic Diagram
MM74HC244
www.fairchildsemi.com 2
Absolute Maximum Ratings(Note 1)
(Note 2)
Supply Voltage (VCC)
DC Input Voltage (V
DC Output Voltage (V
Clamp Diode Current (I
DC Output Current, per pin (I
DC V
or GND Current, per pin (ICC)
CC
Storage Temperature Range (T
Power Dissipation (P
)
IN
)
OUT
, IOK)
IK
)
OUT
)
STG
)
D
(Note 3) 600 mW
S.O. Package only 500 mW
Lead Temperature (T
)
L
(Soldering 10 seconds ) 260
1.5 to V
0.5 to V
65q
0.5 to 7.0V
CC
CC
r
r
r
C to 150qC
20 mA
35 mA
70 mA
Recommended Operating
Conditions
1.5V
Supply Voltage (V
0.5V
DC Input or Output Voltage
(V
IN
, V
OUT
)26V
CC
)0V
Operating Temperature Range (T
Input Rise or Fall Times
, tf) V
(t
r
Note 1: Absolute Maximum Ratings are those values beyond which damage to the device may occur.
Note 2: Unless otherwis e s pecified all voltages are referenced to ground.
q
C
Note 3: Power Dissipation tem perature d erating — plastic “N” package:
12 mW/qC from 65qC to 85qC.
2.0V 1000 ns
CC
V
4.5V 500 ns
CC
V
6.0V 400 ns
CC
Min Max Units
)4085
A
CC
DC Electrical Characteristics (Note 4)
TA
Symbol Parameter Conditions
V
V
V
V
I
I
I
Minimum HIGH Level 2.0V 1.5 1.5 1.5 V
IH
Input Voltage 4.5V 3.15 3.15 3.15 V
Maximum LOW Level 2.0V 0.5 0.5 0.5 V
IL
Input Voltage 4.5V 1.35 1.35 1.35 V
Minimum HIGH Level V
OH
Output Voltage |I
Maximum LOW Level V
OL
Output Voltage |I
Maximum Input V
IN
Current
Maximum 3-STATE V
OZ
Output Leakage V
Current G V
Maximum Quiescent V
CC
Supply Current I
Note 4: For a power supply of 5V r 10% the worst ca se outp ut vo ltages (VOH, and VOL) occur for HC at 4.5V. Thus the 4.5V values s hould be us ed when
designing with this supply. Worst case V
, ICC, and IOZ) occur for CMOS at the higher voltage and so t he 6.0V values shoul d be used.
rent (I
IN
VIH or V
IN
OUT
V
IN
|I
OUT
|I
OUT
IN
OUT
V
IN
|I
OUT
|I
OUT
IN
IN
OUT
IN
OUT
and VIL occur at VCC 5.5V and 4.5V respectively. (The VIH value at 5.5V is 3.85V.) The worst case leakage cur-
IH
IL
| d 20 PA 2.0V 2.0 1.9 1.9 1.9 V
VIH or V
IL
| d 6.0 mA 4.5V 4.2 3.98 3.84 3.7 V
| d 7.8 mA 6.0V 5.7 5.4 5.34 5.2 V
VIH or V
IL
| d 20 PA 2.0V 0 0.1 0.1 0.1 V
VIH or V
IL
| d 6.0 mA 4.5V 0.2 0.26 0.33 0.4 V
| d 7.8 mA 6.0V 0.2 0.26 0.33 0.4 V
VCC or GND 6.0V
VIH, or V
IL
VCC or GND
IH
VCC or GND 6.0V 8.0 80 160
0 PA
V
CC
6.0V 4.2 4.2 4.2 V
6.0V 1.8 1.8 1.8 V
4.5V 4.5 4.4 4.4 4.4 V
6.0V 6.0 5.9 5.9 5.9 V
4.5V 0 0.1 0.1 0.1 V
6.0V 0 0.1 0.1 0.1 V
6.0V
25qCTA
Typ Guaranteed Limits
r
0.1
r
0.5
40 to 85qCTA 55 to 125qC
r
1.0
r
5
r
1.0
r
10
V
q
C
Units
P
P
P
V
A
A
A
MM74HC244
3 www.fairchildsemi.com
Loading...