| 4000 Series |
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| CATEGORIES ABOUT 4000 SERIES | |
| digital electronics | |
| integrated circuits | |
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Initially, the 4000 series was slower than the popular 7400 TTL chips, but had the advantage of much lower Power consumption, the ability to operate over a much wider range of supply Voltage s (3V to 15V) , and simpler Circuit design due to the vastly increased Fanout . However their slower speed (initially only capable of about 1 MHz operation, compared with TTL's 10MHz) meant that their applications were limited to static or slow speed designs. Later, new fabrication technology largely overcame the speed problems, while retaining backward compatibility with most circuit designs. Although all semiconductors can be damaged by Electrostatic Discharge , the high impedance of CMOS inputs made them more susceptible than bipolar, TTL, devices. Eventually, the advantages of CMOS (especially the later series such as 74HC) edged out the older TTL chips, but at the same time ever increasing LSI techniques edged out the modular chip approach to design. The 4000 series is still widely available, but perhaps less important than it was two decades ago. In the 1990s, some manufacturers (e.g. Texas Instruments ) ported the 4000 series to their 74HC / 74HCT series to make chips like the 74HCT4060 that offers the functionality of a 4060 IC but with the speed of the 74HCT chip. The 4000 series permits the use of " Cookbook " design at least for slow design, where standard circuit elements can be created and shared, and connected to other circuits with few, if any, connection difficulties. This greatly speeds up the design of new hardware by reusing standard approaches to circuit design. In contrast, TTL circuits, while similarly modular, often required much more careful interfacing, since the limited fanout (and fan-in) meant that loading of each output had to be carefully considered. Some modern TTL families, like 74LS reduce this problem with fanouts of 20. It is also much easier to prototype LSI designs using the 4000 series and get repeatable and transferrable results when moving to the more integrated design. The series was extended in the late 1970s and 1980s to include new types which implemented new or more greatly integrated functions, or were better versions of existing chips in the 4000 series. Most of these newer chips were given 45xx and 45xxx designations, but are usually still regarded by engineers as part of the 4000 series. EXAMPLE COMMON 4000 SERIES CHIPS
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