Buy Electronic Components

74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

HD74HC148
8-to-3-line Octal Priority Encoder
Description
The HD74HC148 encodes eight data lines to three-line (4-2-1) binary (octal). Cascading circuitry (enable
input EI and enable output EO) is provided to allow octal expansion without the need for external circuitry.
The data inputs and outputs are active at the low logic level.
Features
High Speed Operation: tpd (0 - 7 to A0 - A2) = 15 ns typ (CL = 50 pF)
High Output Current: Fanout of 10 LSTTL Loads
Wide Operating Voltage: VCC = 2 to 6 V
Low Input Current: 1 µA max
Low Quiescent Supply Current: ICC (static) = 4 µA max (Ta = 25°C)
Function Table
Inputs
Outputs
EI 0 1 2 3 4 5 6 7 A2 A1 A0 GS EO
HX X X X X X X X H H H H H
LH H H H H H H H H H H H L
LX X X X X X X L L L L L H
LX X X X X X L H L L H L H
LX X X X X L H H L H L L H
LX X X X L H H H L H H L H
LX X X L H H H H H L L L H
LX X L H H H H H H L H L H
LX L H H H H H H H H L L H
LL H H H H H H H H H H L H
H : High level
L : Low level
X : Irrelevant


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

HD74HC148
Pin Arrangement
41
52
Inputs
63
74
EI 5
Outputs
A2 6
A1 7
GND 8
4
5 EO
6 GS
73
EI 2
A2 1
A1 0
A0
(Top view)
16 VCC
15 EO
Outputs
14 GS
13 3
12 2
11 1
Inputs
10 0
9 A0 Output
2


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

HD74HC148
DC Characteristics
Item
Input voltage
Output voltage
Input current
Quiescent supply
current
Ta = 25°C
Ta = –40 to
+85°C
Symbol
VIH
VCC (V) Min Typ Max Min
2.0 1.5 — — 1.5
4.5 3.15 — — 3.15
Max
Unit
V
6.0 4.2 — — 4.2 —
VIL 2.0 — — 0.5 — 0.5 V
4.5 — — 1.35 — 1.35
6.0 — — 1.8 — 1.8
VOH 2.0 1.9 2.0 — 1.9 — V
4.5 4.4 4.5 — 4.4 —
6.0 5.9 6.0 — 5.9 —
4.5 4.18 — — 4.13 —
6.0 5.68 — — 5.63 —
VOL 2.0 — 0.0 0.1 — 0.1 V
4.5 — 0.0 0.1 — 0.1
6.0 — 0.0 0.1 — 0.1
4.5 — — 0.26 — 0.33
6.0 — — 0.26 — 0.33
Iin 6.0 — — ±0.1 — ±1.0 µA
ICC 6.0 — — 4.0 — 40 µA
Test Conditions
Vin = VIH or VIL IOH = –20 µA
IOH = –4 mA
IOH = –5.2 mA
Vin = VIH or VIL IOL = 20 µA
IOL = 4 mA
IOL = 5.2 mA
Vin = VCC or GND
Vin = VCC or GND, Iout = 0 µA
3


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

HD74HC148
AC Characteristics (CL = 50 pF, Input tr = tf = 6 ns)
Ta = 25°C
Ta = –40 to
+85°C
Item
Symbol
Propagation delay tPLH
time
t PHL
VCC (V)
2.0
4.5
6.0
Min Typ Max Min
— — 230 —
— 15 46 —
— — 39 —
Max Unit
290 ns
58
49
tPLH 2.0 — — 250 — 315 ns
tPHL 4.5 — 16 50 — 63
6.0 — — 43 — 54
tPLH 2.0 — — 270 — 340 ns
tPHL 4.5 — 18 54 — 68
6.0 — — 46 — 58
tPLH 2.0 — — 230 — 290 ns
tPHL 4.5 — 12 46 — 58
6.0 — — 39 — 49
tPLH 2.0 — — 250 — 315 ns
tPHL 4.5 — 12 50 — 63
6.0 — — 43 — 54
tPLH 2.0 — — 270 — 340 ns
tPHL 4.5 — 12 54 — 68
6.0 — — 46 — 58
Output rise/fall
time
t TLH
t THL
2.0 — — 75 — 90 ns
4.5 — 5 15 — 19
6.0 — — 13 — 16
Input capacitance Cin — — 5 10 — 10 pF
Test Conditions
0 - 7 to A0 - A2
0 - 7 to EO
0 - 7 to GS
EI to A0 - A2
EI to GS
EI to EO
4


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

19.20
20.00 Max
16
9
1
1.3
1.11 Max
8
Unit: mm
7.62
2.54 ± 0.25
0.48 ± 0.10
0.25
+
0.13
0.05
0° – 15°
Hitachi Code
JEDEC
EIAJ
Weight (reference value)
DP-16
Conforms
Conforms
1.07 g


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

10.06
10.5 Max
16
9
18
0.80 Max
1.27
*0.42 ± 0.08
0.40 ± 0.06
0.15
0.12 M
*Dimension including the plating thickness
Base material dimension
Unit: mm
7.80
+
0.20
0.30
1.15
0.70 ± 0.20
0° – 8°
Hitachi Code
JEDEC
EIAJ
Weight (reference value)
FP-16DA
Conforms
0.24 g


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

9.9
10.3 Max
16
9
1
1.27
8
0.635 Max
*0.42 ± 0.08
0.40 ± 0.06
0.15
0.25 M
*Dimension including the plating thickness
Base material dimension
Unit: mm
6.10
+
0.10
0.30
1.08
0.60
+
0.67
0.20
0° – 8°
Hitachi Code
JEDEC
EIAJ
Weight (reference value)
FP-16DN
Conforms
Conforms
0.15 g


74HC148 Datasheet PDF
No Preview Available !

Click to Download PDF File

Cautions
1. Hitachi neither warrants nor grants licenses of any rights of Hitachi’s or any third party’s patent,
copyright, trademark, or other intellectual property rights for information contained in this document.
Hitachi bears no responsibility for problems that may arise with third party’s rights, including
intellectual property rights, in connection with use of the information contained in this document.
2. Products and product specifications may be subject to change without notice. Confirm that you have
received the latest product standards or specifications before final design, purchase or use.
3. Hitachi makes every attempt to ensure that its products are of high quality and reliability. However,
contact Hitachi’s sales office before using the product in an application that demands especially high
quality and reliability or where its failure or malfunction may directly threaten human life or cause risk
of bodily injury, such as aerospace, aeronautics, nuclear power, combustion control, transportation,
traffic, safety equipment or medical equipment for life support.
4. Design your application so that the product is used within the ranges guaranteed by Hitachi particularly
for maximum rating, operating supply voltage range, heat radiation characteristics, installation
conditions and other characteristics. Hitachi bears no responsibility for failure or damage when used
beyond the guaranteed ranges. Even within the guaranteed ranges, consider normally foreseeable
failure rates or failure modes in semiconductor devices and employ systemic measures such as fail-
safes, so that the equipment incorporating Hitachi product does not cause bodily injury, fire or other
consequential damage due to operation of the Hitachi product.
5. This product is not designed to be radiation resistant.
6. No one is permitted to reproduce or duplicate, in any form, the whole or part of this document without
written approval from Hitachi.
7. Contact Hitachi’s sales office for any questions regarding this document or Hitachi semiconductor
products.
Hitachi, Ltd.
Semiconductor & Integrated Circuits.
Nippon Bldg., 2-6-2, Ohte-machi, Chiyoda-ku, Tokyo 100-0004, Japan
Tel: Tokyo (03) 3270-2111 Fax: (03) 3270-5109
URL
NorthAmerica
Europe
Asia (Singapore)
Asia (Taiwan)
Asia (HongKong)
Japan
: http:semiconductor.hitachi.com/
: http://www.hitachi-eu.com/hel/ecg
: http://www.has.hitachi.com.sg/grp3/sicd/index.htm
: http://www.hitachi.com.tw/E/Product/SICD_Frame.htm
: http://www.hitachi.com.hk/eng/bo/grp3/index.htm
: http://www.hitachi.co.jp/Sicd/indx.htm
For further information write to:
Hitachi Semiconductor
(America) Inc.
179 East Tasman Drive,
San Jose,CA 95134
Tel: <1> (408) 433-1990
Fax: <1>(408) 433-0223
Hitachi Europe GmbH
Electronic components Group
Dornacher Stra§e 3
D-85622 Feldkirchen, Munich
Germany
Tel: <49> (89) 9 9180-0
Fax: <49> (89) 9 29 30 00
Hitachi Europe Ltd.
Electronic Components Group.
Whitebrook Park
Lower Cookham Road
Maidenhead
Berkshire SL6 8YA, United Kingdom
Tel: <44> (1628) 585000
Fax: <44> (1628) 778322
Hitachi Asia Pte. Ltd.
Hitachi Asia (Hong Kong) Ltd.
16 Collyer Quay #20-00
Group III (Electronic Components)
Hitachi Tower
7/F., North Tower, World Finance Centre,
Singapore 049318
Harbour City, Canton Road, Tsim Sha Tsui,
Tel: 535-2100
Kowloon, Hong Kong
Fax: 535-1533
Tel: <852> (2) 735 9218
Fax: <852> (2) 730 0281
Hitachi Asia Ltd.
Telex: 40815 HITEC HX
Taipei Branch Office
3F, Hung Kuo Building. No.167,
Tun-Hwa North Road, Taipei (105)
Tel: <886> (2) 2718-3666
Fax: <886> (2) 2718-8180
Copyright ' Hitachi, Ltd., 1999. All rights reserved. Printed in Japan.





Click to Download PDF File