
5-24
FAST AND LS TTL DATA
SCHMITT TRIGGERS
DUAL GATE/HEX INVERTER
The SN54LS/74LS13 and SN54LS/74LS14 contain logic gates/inverters
which accept standard TTL input signals and provide standard TTL output
levels. They are capable of transforming slowly changing input signals into
sharply defined, jitter-free output signals. Additionally, they have greater noise
margin than conventional inverters.
Each circuit contains a Schmitt trigger followed by a Darlington level shifter
and a phase splitter driving a TTL totem pole output. The Schmitt trigger uses
positive feedback to effectively speed-up slow input transitions, and provide
different input threshold voltages for positive and negative-going transitions.
This hysteresis between the positive-going and negative-going input
thresholds (typically 800 mV) is determined internally by resistor ratios and is
essentially insensitive to temperature and supply voltage variations.
14
13
12
11
10
9
1
2
3
4
5
6
VCC
8
7
GND
LOGIC AND CONNECTION DIAGRAMS
SN54/74LS13
SN54/74LS14
14
13
12
11
10
9
1
2
3
4
5
6
VCC
8
7
GND
GUARANTEED OPERATING RANGES
Symbol
Parameter
Min
Typ
Max
Unit
VCC
Supply Voltage
54
74
4.5
4.75
5.0
5.0
5.5
5.25
V
TA
Operating Ambient Temperature Range
54
74
–55
0
25
25
125
70
°
C
IOH
IOL
Output Current — High
54, 74
–0.4
mA
Output Current — Low
54
74
4.0
8.0
mA
SN54/74LS13
SN54/74LS14
SCHMITT TRIGGERS
DUAL GATE/HEX INVERTER
LOW POWER SCHOTTKY
J SUFFIX
CERAMIC
CASE 632-08
N SUFFIX
PLASTIC
CASE 646-06
14
1
14
1
ORDERING INFORMATION
SN54LSXXJ
SN74LSXXN
SN74LSXXD
Ceramic
Plastic
SOIC
14
1
D SUFFIX
SOIC
CASE 751A-02