Datasheet > 74HC191D

74HC191D

更新时间： 2023-09-03 20:30:40

品牌	Logo	应用领域
安世 - NEXPERIA		光电二极管输出元件逻辑集成电路触发器
页数	文件大小	规格书
18页	291K
描述
Presettable synchronous 4-bit binary up/down counterProduction

阅读下载

中文翻译

获取价格

技术参数
数据手册
替代型号

如果您发现信息不准确，欢迎纠错

74HC191D 技术参数

是否Rohs认证：	符合	生命周期：	Active
包装说明：	SOP,	Reach Compliance Code：	compliant
ECCN代码：	EAR99	HTS代码：	8542.39.00.01
风险等级：	1.16	其他特性：	TCO OUTPUT
计数方向：	BIDIRECTIONAL	系列：	HC/UH
JESD-30 代码：	R-PDSO-G16	JESD-609代码：	e4
长度：	9.9 mm	负载电容（CL）：	50 pF
负载/预设输入：	YES	逻辑集成电路类型：	BINARY COUNTER
工作模式：	SYNCHRONOUS	湿度敏感等级：	1
位数：	4	功能数量：	1
端子数量：	16	最高工作温度：	125 °C
最低工作温度：	-40 °C	封装主体材料：	PLASTIC/EPOXY
封装代码：	SOP	封装形状：	RECTANGULAR
封装形式：	SMALL OUTLINE	峰值回流温度（摄氏度）：	260
传播延迟（tpd）：	66 ns	认证状态：	Not Qualified
座面最大高度：	1.75 mm	最大供电电压 (Vsup)：	6 V
最小供电电压 (Vsup)：	2 V	标称供电电压 (Vsup)：	5 V
表面贴装：	YES	技术：	CMOS
温度等级：	AUTOMOTIVE	端子面层：	Nickel/Palladium/Gold (Ni/Pd/Au)
端子形式：	GULL WING	端子节距：	1.27 mm
端子位置：	DUAL	处于峰值回流温度下的最长时间：	30
触发器类型：	POSITIVE EDGE	宽度：	3.9 mm
最小 fmax：	13 MHz	Base Number Matches：	1

74HC191D 数据手册

74HC191

Presettable synchronous 4-bit binary up/down counter

Rev. 6 — 8 September 2021

Product data sheet

1. General description

The 74HC191 is an asynchronously presettable 4-bit binary up/down counter. It contains four

master/slave flip-flops with internal gating and steering logic to provide asynchronous preset and

synchronous count-up and count-down operation. Asynchronous parallel load capability permits

the counter to be preset to any desired value. Information present on the parallel data inputs (D0

to D3) is loaded into the counter and appears on the outputs when the parallel load (PL) input is

LOW. This operation overrides the counting function. Counting is inhibited by a HIGH level on the

count enable (CE) input. When CE is LOW internal state changes are initiated synchronously by

the LOW-to-HIGH transition of the clock input. The up/down (U/D) input signal determines the

direction of counting as indicated in the function table. The CE input may go LOW when the clock is

in either state, however, the LOW-to-HIGH CE transition must occur only when the clock is HIGH.

Also, the U/D input should be changed only when either CE or CP is HIGH. Overflow/underflow

indications are provided by two types of outputs, the terminal count (TC) and ripple clock (RC).

The TC output is normally LOW and goes HIGH when a circuit reaches zero in the count-down

mode or reaches '15' in the count-up-mode. The TC output will remain HIGH until a state change

occurs, either by counting or presetting, or until U/D is changed. Do not use the TC output as a

clock signal because it is subject to decoding spikes. The TC signal is used internally to enable

the RC output. When TC is HIGH and CE is LOW, the RC output follows the clock pulse (CP). This

feature simplifies the design of multistage counters as shown in Fig. 5 and Fig. 6. In Fig. 5, each

RC output is used as the clock input to the next higher stage. It is only necessary to inhibit the

first stage to prevent counting in all stages, since a HIGH on CE inhibits the RC output pulse. The

timing skew between state changes in the first and last stages is represented by the cumulative

delay of the clock as it ripples through the preceding stages. This can be a disadvantage of this

configuration in some applications. Fig. 6 shows a method of causing state changes to occur

simultaneously in all stages. The RC outputs propagate the carry/borrow signals in ripple fashion

and all clock inputs are driven in parallel. In this configuration the duration of the clock LOW state

must be long enough to allow the negative-going edge of the carry/borrow signal to ripple through

to the last stage before the clock goes HIGH. Since the RC output of any package goes HIGH

shortly after its CP input goes HIGH there is no such restriction on the HIGH-state duration of the

clock. In Fig. 7, the configuration shown avoids ripple delays and their associated restrictions.

Combining the TC signals from all the preceding stages forms the CE input for a given stage. An

enable must be included in each carry gate in order to inhibit counting. The TC output of a given

stage it not affected by its own CE signal therefore the simple inhibit scheme of Fig. 5 and Fig. 6

does not apply. Inputs include clamp diodes. This enables the use of current limiting resistors to

interface inputs to voltages in excess of V_CC

2. Features and benefits

•

Wide supply voltage range from 2.0 to 6.0 V

•

CMOS low power dissipation

High noise immunity

Latch-up performance exceeds 100 mA per JESD 78 Class II Level B

CMOS input levels

Synchronous reversible counting

Asynchronous parallel load

Count enable control for synchronous expansion

Single up/down control input

12 3 4 5 6 7...18

中文翻译

下载PDF

74HC191D 替代型号

型号	品牌	替代类型	描述	数据表
CD74HC191M	TI	功能相似	SYNCHRONOUS UP/DOWN COUNTERS WITH DOWN/UP MODE CONTROL
SN74HC191D	TI	功能相似	4-BIT SYNCHRONOUS UP/DOWN BINARY COUNTERS

与74HC191D相关器件

型号	品牌	获取价格	描述	数据表
74HC191DB	NXP	获取价格	Presettable synchronous 4-bit binary up/down counter
74HC191DB,112	NXP	获取价格	74HC(T)191 - Presettable synchronous 4-bit binary up/down counter SSOP1 16-Pin
74HC191DB,118	NXP	获取价格	74HC(T)191 - Presettable synchronous 4-bit binary up/down counter SSOP1 16-Pin
74HC191DB-T	NXP	获取价格	IC HC/UH SERIES, SYN POSITIVE EDGE TRIGGERED 4-BIT BIDIRECTIONAL BINARY COUNTER, PDSO16, S
74HC191D-T	ETC	获取价格	Synchronous Up/Down Counter
74HC191N	NXP	获取价格	Presettable synchronous 4-bit binary up/down counter
74HC191N,652	NXP	获取价格	74HC(T)191 - Presettable synchronous 4-bit binary up/down counter DIP 16-Pin
74HC191N-B	PHILIPS	获取价格	Binary Counter, Synchronous, Bidirectional, CMOS, PDIP16
74HC191PW	NXP	获取价格	Presettable synchronous 4-bit binary up/down counter
74HC191PW	NEXPERIA	获取价格	Presettable synchronous 4-bit binary up/down counterProduction

与74HC191D相关文章

REF70数据手册解读：高精度电压参考源的全面剖析
2024-07-08

2
解析30211801数据手册：PCB端子排MKDSV 5/3-9.5
2024-07-08

1
UL248-14数据手册深度解读：微型保险丝的全面剖析
2024-07-08

3
BSS138LT3G：一款高效能N沟道MOSFET的全面解析
2024-07-04

17

产品中心

服务支持

精选活动

关于我们

帮助中心

74HC191D

74HC191D 技术参数

74HC191D 数据手册

74HC191D 替代型号

与74HC191D相关器件

与74HC191D相关文章

您还可以找

产品中心

服务支持

精选活动

关于我们

帮助中心

74HC191D

74HC191D 技术参数

74HC191D 数据手册

74HC191D 替代型号

与74HC191D相关器件

与74HC191D相关文章

您还可以找

您在本页遇到什么问题？