CD54HC191 高速 CMOS 逻辑可预设置的同步 4 位二进制加/减计数器

The CD54/74HC190 are asynchronously presettable BCD decade counters, whereas the CD54/74HC191 and CD54/74HCT191 are asynchronously presettable binary counters.

Presetting the counter to the number on preset data inputs (A–D) is accomplished by a low asynchronous parallel load (LOAD)\ input. Counting occurs when LOAD\ is high, count enable (CTEN)\ is low, and the down/up (D/U) input is either high for down counting or low for up counting. The counter is decremented or incremented synchronously with the low-to-high transition of the clock.

When an overflow or underflow of the counter occurs, the MAX/MIN output, which is low during counting, goes high and remains high for one clock cycle. This output can be used for look-ahead carry in high-speed cascading (see Figure 1).

	CD54HC191
Rating	Military
Technology Family	HC

CD54HC191 特性

• 2-V to 6-V VCC Operation (’HC190,191)
• 4.5-V to 5.5-V VCC Operation (’HCT191)
• Wide Operating Temperature Range of –55 to 125°C
• Synchronous Counting and Asynchronous Loading
• Two Outputs for n-Bit Cascading
• Look-Ahead Carry for High-Speed Counting
• Balanced Propagation Delay and Transition Times
• Standard Outputs Drive Up To 15 LS-TTL Loads
• Significant Power Reduction Compared to LS-TTL Logic ICs

CD54HC191 芯片订购指南

器件	状态	温度	价格	封装 | 引脚	封装数量 | 封装载体	丝印标记
CD54HC191F3A	ACTIVE	-55 to 125	4.10 | 1ku	CDIP (J) | 16	1 | TUBE

CD54HC191 质量与无铅数据

器件	环保计划*	铅/焊球涂层	MSL 等级/回流焊峰	环保信息与无铅 (Pb-free)	DPPM / MTBF / FIT 率
CD54HC191F3A	TBD	A42	N/A for Pkg Type	CD54HC191F3A	CD54HC191F3A

CD54HC191 应用技术支持与电子电路设计开发资源下载

1. CD54HC191 数据资料 dataSheet 下载.PDF
2. TI 德州仪器MSI 功能产品选型与价格 . xls
3. Logic Guide 2009 (PDF 4263 KB)
4. Shelf-Life Evaluation of Lead-Free Component Finishes (PDF 1305 KB)
5. Understanding and Interpreting Standard-Logic Data Sheets (PDF 857 KB)
6. TI IBIS File Creation, Validation, and Distribution Processes (PDF 380 KB)
7. Implications of Slow or Floating CMOS Inputs (PDF 101 KB)
8. CMOS Power Consumption and CPD Calculation (PDF 89 KB)
9. Designing With Logic (PDF 186 KB)
10. Live Insertion (PDF 150 KB)
11. Input and Output Characteristics of Digital Integrated Circuits (PDF 1708 KB)
12. Using High Speed CMOS and Advanced CMOS in Systems With Multiple Vcc (PDF 43 KB)
13. HiRel Unitrode Power Management Brochure (PDF 206 KB)
14. LOGIC Pocket Data Book (PDF 6001 KB)
15. HiRel Unitrode Power Management Brochure (PDF 206 KB)
16. Logic Cross-Reference (PDF 2938 KB)