To learn more about ON Semiconductor, please visit our website at
www.onsemi.com
Please note: As part of the Fairchild Semiconductor integration, some of the Fairchild orderable part numbers
will need to change in order to meet ON Semiconductor’s system requirements. Since the ON Semiconductor
product management systems do not have the ability to manage part nomenclature that utilizes an underscore
(_), the underscore (_) in the Fairchild part numbers will be changed to a dash (-). This document may contain
device numbers with an underscore (_). Please check the ON Semiconductor website to verify the updated
device numbers. The most current and up-to-date ordering information can be found at
www.onsemi.com.
Please
email any questions regarding the system integration to
Fairchild_questions@onsemi.com.
ON Semiconductor and the ON Semiconductor logo are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries. ON Semiconductor owns the rights to a number
of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductor’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. ON Semiconductor reserves the right
to make changes without further notice to any products herein. ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. Buyer is responsible for its products and applications using ON
Semiconductor products, including compliance with all laws, regulations and safety requirements or standards, regardless of any support or applications information provided by ON Semiconductor. “Typical” parameters which may be provided in ON
Semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s
technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any FDA
Class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for implantation in the human body. Should Buyer purchase or use ON Semiconductor products for any such unintended
or unauthorized application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out
of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor
is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
74VHC157 Quad 2-Input Multiplexer
May 2007
74VHC157
Quad 2-Input Multiplexer
Features
■
High Speed: t
PD
=
4.1ns (Typ.) at V
CC
=
5V
■
Low power dissipation: I
CC
=
4µA (Max.) at T
A
=
25°C
■
High noise immunity: V
NIH
=
V
NIL
=
28% V
CC
(Min.)
■
Power down protection is provided on all inputs
■
Low noise: V
OLP
=
0.8V (Max.)
■
Pin and function compatible with 74HC157
tm
General Description
The VHC157 is an advanced high speed CMOS Quad
2-Channel Multiplexer fabricated with silicon gate CMOS
technology. It achieves the high speed operation similar
to equivalent Bipolar Schottky TTL while maintaining the
CMOS low power dissipation.
It consists of four 2-input digital multiplexers with com-
mon select and enable inputs. When the ENABLE input
is held “H” level, selection of data is inhibited and all the
outputs become “L” level. The SELECT decoding deter-
mines whether the I
0x
or I
1x
inputs get routed to their cor-
responding outputs.
An Input protection circuit ensures that 0V to 7V can be
applied to the input pins without regard to the supply
voltage. This device can be used to interface 5V to 3V
systems and on two supply systems such as battery
back up. This circuit prevents device destruction due to
mismatched supply and input voltages.
Ordering Information
Order Number
74VHC157M
74VHC157SJ
74VHC157MTC
Package
Number
M16A
M16D
MTC16
Package Description
16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150”
Narrow
16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
16-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153,
4.4mm Wide
Surface mount packages are also available on Tape and Reel. Specify by appending the suffix letter “X” to the
中风发生时,一切都是以秒来计算的。延误治疗可能导致大脑重大损伤。伦敦大学医学院的一位博士Alistair McEwan已经获得行为医学研究所(Action Medical Research)的同意,为急救人员开发一种无线诊断系统来减少时间延误。感谢抗血栓药物,一些病人在病情发作的三个小时之内可以完全恢复。但出血也会导致中风。医生在治疗之前需要确定发病原因,因为不适当的服用抗血栓药物会加重损害。...[详细]
便携式医疗设备的特殊性决定了它们应该是对用户友好的、必须工作在无菌环境下,并且空间占用小、耗能低。 同时,便携式医疗设备还需要足够的计算能力以便处理医疗数据,能够连接到无线或有线接口以便记录和发送数据。从设计人员的角度考虑,上述需求需要低功耗的单片机(MCU)和数字信号控制器(Digital Signal Controller,DSC)。 正是有了嵌入式处理器,设计人员才有可能设...[详细]