数据搜索系统,热门电子元器件搜索
  Chinese▼

Delete All
ON OFF
ALLDATASHEETCN.COM

X  

预览 PDF Download HTML

74HC163 Datasheet(数据表) 2 Page - NXP Semiconductors

部件型号  74HC163
说明  Presettable synchronous 4-bit binary counter; synchronous reset
下载  11 Pages
Scroll/Zoom Zoom In 100% Zoom Out
制造商  PHILIPS [NXP Semiconductors]
网页  http://www.nxp.com
标志 

74HC163 Datasheet(HTML) 2 Page - NXP Semiconductors

 
Zoom Inzoom in Zoom Outzoom out
 2 page
background image
December 1990
2
Philips Semiconductors
Product specification
Presettable synchronous 4-bit binary
counter; synchronous reset
74HC/HCT163
FEATURES
• Synchronous counting and loading
• Two count enable inputs for n-bit cascading
• Positive-edge triggered clock
• Synchronous reset
• Output capability: standard
• ICC category: MSI
GENERAL DESCRIPTION
The 74HC/HCT163 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.
The 74HC/HCT163 are synchronous presettable binary
counters which feature an internal look-ahead carry and
can be used for high-speed counting.
Synchronous operation is provided by having all flip-flops
clocked simultaneously on the positive-going edge of the
clock (CP).
The outputs (Q0 to Q3) of the counters may be preset to a
HIGH or LOW level. A LOW level at the parallel enable
input (PE) disables the counting action and causes the
data at the data inputs (D0 to D3) to be loaded into the
counter on the positive-going edge of the clock (providing
that the set-up and hold time requirements for PE are met).
Preset takes place regardless of the levels at count enable
inputs (CEP and CET).
For the “163” the clear function is synchronous.
A LOW level at the master reset input (MR) sets all four
outputs of the flip-flops (Q0 to Q3) to LOW level after the
next positive-going transition on the clock (CP) input
(provided that the set-up and hold time requirements for
MR are met). This action occurs regardless of the levels at
PE, CET and CEP inputs.
This synchronous reset feature enables the designer to
modify the maximum count with only one external NAND
gate.
The look-ahead carry simplifies serial cascading of the
counters. Both count enable inputs (CEP and CET) must
be HIGH to count. The CET input is fed forward to enable
the terminal count output (TC). The TC output thus
enabled will produce a HIGH output pulse of a duration
approximately equal to a HIGH level output of Q0. This
pulse can be used to enable the next cascaded stage.
The maximum clock frequency for the cascaded counters
is determined by the CP to TC propagation delay and CEP
to CP set-up time, according to the following formula:
fmax
1
t
P max
() (CPtoTC)
t
SU (CEP to CP)
+
-------------------------------------------------------------------------------------------------
=
QUICK REFERENCE DATA
GND = 0 V; Tamb =25 °C; tr =tf =6ns
SYMBOL
PARAMETER
CONDITIONS
TYPICAL
UNIT
HC
HCT
tPHL/ tPLH
propagation delay
CP to Qn
CP to TC
CET to TC
CL =15pF;
VCC =5V
17
21
11
20
25
14
ns
ns
ns
fmax
maximum clock frequency
51
50
MHz
CI
input capacitance
3.5
3.5
pF
CPD
power dissipation
capacitance per package
notes 1 and 2
33
35
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




HTML 页

1  2  3  4  5  6  7  8  9  10  11 


数据表 下载




链接网址


Privacy Policy
ALLDATASHEETCN.COM
ALLDATASHEET是否为您带来帮助?  [ DONATE ]  

关于 Alldatasheet    |   广告服务   |   联系我们   |   隐私政策   |   书签   |   链接交换   |   制造商名单
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  , Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp  |   Russian : Alldatasheetru.com
Korean : Alldatasheet.co.kr   |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com  |   Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl