74HCT182 [NXP]
Look-ahead carry generator; 先行进位发生器
| 型号： | 74HCT182 |
| 厂家： | 
NXP |
| 描述： | Look-ahead carry generator |
| 文件： | 总9页 (文件大小：70K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
INTEGRATED CIRCUITS
DATA SHEET
For a complete data sheet, please also download:
• The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
• The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
• The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
74HC/HCT182
Look-ahead carry generator
December 1990
Product specification
File under Integrated Circuits, IC06
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
anticipated active HIGH carries (Cn+x, Cn+y, Cn+z) across
four groups of binary adders.
FEATURES
• Provides carry look-ahead across a group of four ALU’s
The “182” also has active LOW carry propagate (P) and
carry generate (G) outputs which may be used for further
levels of look-ahead.
• Multi-level look-ahead for high-speed arithmetic
operation over long word length
• Output capability: standard
• ICC category: MSI
The logic equations provided at the outputs are:
Cn+x = G0 + P0Cn
Cn+y = G1 + P1G0 + P1P0Cn
Cn+z = G2 + P2G1 + P2P1G0 + P2P1P0Cn
GENERAL DESCRIPTION
The 74HC/HCT182 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.
G = G3 + P3G2 + P3P2G1 + P3P2P1GO
P = P3P2P1P0
The “182” can also be used with binary ALU’s in an active
LOW or active HIGH input operand mode. The
connections to and from the ALU to the carry look-ahead
generator are identical in both cases.
The 74HC/HCT182 carry look-ahead generators accept
up to four pairs of active LOW carry propagate (P0, P1, P2,
P3) and carry generate (G0, G1, G2, G3) signals and an
active HIGH carry input (Cn). The devices provide
QUICK REFERENCE DATA
GND = 0 V; Tamb = 25 °C; tr = tf = 6 ns
TYPICAL
SYMBOL
PARAMETER
CONDITIONS
CL = 15 pF; VCC = 5 V
UNIT
HC
HCT
tPHL/ tPLH
propagation delay
Pn to P
Cn to any output
Pn or Gn to any output
11
17
14
14
21
17
ns
ns
ns
CI
input capacitance
3.5
3.5
pF
CPD
power dissipation capacitance per
package
notes 1 and 2
50
50
pF
Notes
1. CPD is used to determine the dynamic power dissipation (PD in µW):
PD = CPD × VCC2 × fi + ∑ (CL × VCC2 × fo) where:
fi = input frequency in MHz
fo = output frequency in MHz
∑ (CL × VCC2 × fo) = sum of outputs
CL = output load capacitance in pF
VCC = supply voltage in V
2. For HC the condition is VI = GND to VCC
For HCT the condition is VI = GND to VCC − 1.5 V
ORDERING INFORMATION
See “74HC/HCT/HCU/HCMOS Logic Package Information”.
December 1990
2
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
PIN DESCRIPTION
PIN NO.
SYMBOL
NAME AND FUNCTION
3, 1, 14, 5
G0 to G3
P0 to P3
P
carry generate inputs (active LOW)
carry propagate inputs (active LOW)
carry propagate output (active LOW)
ground (0 V)
4, 2, 15, 6
7
8
GND
Cn+z
G
9
function output
10
11
12
13
16
carry generate output (active LOW)
function output
Cn+y
Cn+x
Cn
function output
carry input (active HIGH)
positive supply voltage
VCC
Fig.1 Pin configuration.
Fig.2 Logic symbol.
Fig.3 IEC logic symbol.
December 1990
3
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
Fig.4 Functional diagram.
Fig.5 Logic diagram.
December 1990
4
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
FUNCTION TABLE
INPUTS
OUTPUTS
Cn+y Cn+z
Cn
G0
P0
G1
P1
G2
P2
G3
P3
Cn+x
G
P
X
L
X
H
H
H
L
H
X
X
L
L
L
H
H
X
X
X
L
X
X
H
X
H
H
X
L
X
H
X
X
X
L
H
H
H
L
X
X
H
X
X
X
L
L
L
L
H
H
H
X
L
X
X
X
L
X
X
H
H
X
X
H
X
X
H
H
H
X
H
X
X
H
H
H
H
H
X
X
X
L
L
L
L
X
X
X
H
X
X
L
X
X
X
L
X
L
X
X
X
X
L
L
L
X
L
L
L
H
H
H
H
X
X
X
X
X
X
X
H
X
X
H
H
X
X
H
X
X
H
H
H
X
H
X
X
H
H
H
H
H
X
X
X
H
H
H
H
X
X
X
L
X
X
L
X
X
X
L
X
L
X
X
X
X
L
L
L
X
L
L
L
L
L
L
L
X
X
X
X
H
X
X
X
L
X
H
X
X
L
X
X
H
X
L
X
X
X
H
L
H
H
H
H
L
Notes
1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
December 1990
5
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
DC CHARACTERISTICS FOR 74HC
For the DC characteristics see “74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: standard
ICC category: MSI
AC CHARACTERISTICS FOR 74HC
GND = 0 V; tr = tf = 6 ns; CL = 50 pF
Tamb (°C)
TEST CONDITIONS
74HC
SYMBOL PARAMETER
UNIT
WAVEFORMS
VCC
(V)
+25
−40 to +85
−40 to +125
min. typ. max. min. max. min. max.
tPHL/ tPLH propagation delay
Pn to P
30
14
11
120
24
20
150
30
26
180
36
31
ns
ns
ns
ns
ns
ns
ns
2.0
4.5
6.0
Fig.6
Fig.6
Fig.6
Fig.6
Fig.6
Fig.6
Fig.6
t
t
t
t
PHL/ tPLH propagation delay
Cn to any output
55
20
16
170
34
29
215
43
37
255
51
43
2.0
4.5
6.0
PHL/ tPLH propagation delay
Pn to G
47
17
14
145
29
25
180
36
31
220
44
38
2.0
4.5
6.0
PHL/ tPLH propagation delay
Pn to Cn+n
47
17
14
145
29
25
180
36
31
220
44
38
2.0
4.5
6.0
PHL/ tPLH propagation delay
Gn to Cn+n
44
16
13
135
27
23
170
34
29
205
41
35
2.0
4.5
6.0
tPHL/ tPLH propagation delay
Gn to G
41
15
12
135
27
23
170
34
29
205
41
35
2.0
4.5
6.0
t
THL/ tTLH output transition time
19
7
6
75
15
13
95
19
16
110
22
19
2.0
4.5
6.0
December 1990
6
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
DC CHARACTERISTICS FOR 74HCT
For the DC characteristics see “74HC/HCT/HCU/HCMOS Logic Family Specifications”.
Output capability: standard
ICC category: MSI
Note to HCT types
The value of additional quiescent supply current (∆ICC) for a unit load of 1 is given in the family specifications.
To determine ∆ICC per input, multiply this value by the unit load coefficient shown in the table below.
INPUT
UNIT LOAD COEFFICIENT
G0, G1, P0, P1, P2
G3
G2, P3, Cn
1.50
0.30
1.25
AC CHARACTERISTICS FOR 74HCT
GND = 0 V; tr = tf = 6 ns; CL = 50 pF
Tamb (°C)
74HCT
TEST CONDITIONS
SYMBOL PARAMETER
UNIT
WAVEFORMS
VCC
(V)
+25
−40 to +85
−40 to +125
min. typ. max. min. max. min. max.
tPHL/ tPLH propagation delay
Pn to P
17
26
20
20
18
7
28
43
33
33
32
15
35
54
41
41
40
19
42
65
50
50
48
22
ns
ns
ns
ns
ns
ns
4.5
4.5
4.5
4.5
4.5
4.5
Fig.6
Fig.6
Fig.6
Fig.6
Fig.6
Fig.6
tPHL/ tPLH propagation delay
Cn to any output
t
PHL/ tPLH propagation delay
Pn to G
tPHL/ tPLH propagation delay
Pn to Cn+n
tPHL/ tPLH propagation delay
Gn to Cn+n, Gn to G
t
THL/ tTLH output transition time
December 1990
7
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
AC WAVEFORMS
(1) HC : VM = 50%; VI = GND to VCC
.
HCT: VM = 1.3 V; VI = GND to 3 V.
Fig.6 Waveforms showing the input (Pn, Cn, Gn) to any output propagation delays and the output transition times.
APPLICATION INFORMATION
A and B inputs and F outputs of “181” are not shown.
Fig.7 16-bit ALU two-level look-ahead.
A and B inputs and F outputs of “181” are not shown.
Fig.8 32-bit ALU two-level look-ahead over 16-bit groups.
December 1990
8
Philips Semiconductors
Product specification
Look-ahead carry generator
74HC/HCT182
A and B inputs and F outputs of “181” are not shown.
Fig.9 Combined two-level look-ahead and ripple-carry ALU.
A and B inputs and F outputs of “181” are not shown.
Fig.10 64-bit ALU full-carry three-level look-ahead.
PACKAGE OUTLINES
See “74HC/HCT/HCU/HCMOS Logic Package Outlines”.
December 1990
9
相关型号：
©2020 ICPDF网 联系我们和版权申明