Fairchild DM74LS27 service manual

查询DM74LS27供应商

DM74LS27
Triple 3-Input NOR Gate

General Description

This device contains three independent gates each of
which performs the logic NOR function.

Ordering Code:

Order Number Package Number Package Description

DM74LS27M M14A 14-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-120, 0.150 Narrow
DM74LS27N N14A 14-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering cod e.

DM74LS27 Tri ple 3-Input NOR Gate

May 1986
Revised March 2000

Connection Diagram Function Table

Inputs Output

ABCY

LLLH
XXHL
XHXL
HXXL

H = HIGH Logic Level
L = LOW Logic Level
X = Either LOW or HIGH Logic Level

Y = A + B + C

© 2000 Fairchild Semiconductor Corporation DS006359 www.fairchildsemi.com

Absolute Maximum Ratings(Note 1)

Supply Voltage 7V
Input Voltage 7V
Operating Free Air Temperature Range 0°C to +70°C

DM74LS27

Storage Temperature Range −65°C to +150°C

Note 1: The “Absolute Maximum Ratings” are those values beyond which
the safety of the dev ice cannot be guaranteed. T he device sh ould not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommend ed O peratin g Cond itions” t able w ill defin e the c ondit ions
for actual device operation.

Recommended Operating Conditions

Symbol Parameter Min Nom Max Units

V

CC

V

IH

V

IL

I

OH

I

OL

T

A

Supply Voltage 4.75 5 5. 25 V
HIGH Level Input Voltage 2 V
LOW Level In put Vo ltage 0.8 V
HIGH Level Output Current −0.4 mA
LOW Level Ou tput Current 8 mA
Free Air Operating Temperature 0 70 °C

Electrical Characteristics

over recommended operating free air temperature range (unless otherwise noted)

Symbol Parameter Conditions Min

V

I

V

OH

V

OL

I

I

I

IH

I

IL

I

OS

I

CCH

I

CCL

Note 2: All typicals are at VCC = 5V, TA = 25°C.
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.

Input Clamp Voltage VCC = Min, II = −18 mA −1.5 V
HIGH Level VCC = Min, IOH = Max,
Output Voltage VIL = Max
LOW Level VCC = Min, IOL = Max,
Output Voltage VIH = Min V

IOL = 4 mA, VCC = Min 0.25 0.4
Input Current @ Max Input Voltage VCC = Max, VI = 7V 0.1 mA
HIGH Level Input Current VCC = Max, VI = 2.7V 20 µA
LOW Level Input Current VCC = Max, VI = 0.4V −0.36 mA
Short Circuit Output Current VCC = Max (Note 3) −20 −100 mA
Supply Current with Outputs HIGH VCC = Max 2 4 mA
Supply Current with Outputs LOW VCC = Max 3.4 6.8 mA

2.7 3.4 V

Typ

(Note 2)

0.35 0.5

Max Units

Switching Characteristics

at VCC = 5V and TA = 25°C

Symbol Parameter

t

PLH

t

PHL

www.fairchildsemi.com 2

Propagation Delay Time
LOW-to-HIGH Level Output
Propagation Delay Time
HIGH-to-LOW Level Output

CL = 15 pF CL = 50 pF

Min Max Min Max

313518ns

310415ns

RL = 2 kΩ

Units