Search results
Results From The WOW.Com Content Network
The two options are active high (positive logic) and active low (negative logic). Active-high and active-low states can be mixed at will: for example, a read only memory integrated circuit may have a chip-select signal that is active-low, but the data and address bits are conventionally active-high. Occasionally a logic design is simplified by ...
Input column – a blank cell means a normal input for the logic family type. Output column – a blank cell means a "totem pole" output, also known as a push–pull output, with the ability to drive ten standard inputs of the same logic subfamily (fan-out N O = 10). Outputs with higher output currents are often called drivers or buffers.
The 74181 implements all 16 possible logical functions with two variables. Its arithmetic functions include addition and subtraction with and without carry. It can be used with active-high data, in which a high logic level corresponds to 1, and active-low data, in which a low logic level corresponds to 1. [4]
If all inputs are high, each buffer will be in a high-impedance state and the pull-up resistor will pull the output high. But if any input is low, the output will be pulled low by the buffer for that input. This corresponds to wired AND in active-high logic, or to wired OR in active-low logic, and allows multiple inputs to share the same output ...
The following diode logic gates work in both active-high or active-low logic, however the logical function they implement is different depending on what voltage level is considered active. Switching between active-high and active-low is commonly used to achieve a more efficient logic design.
Typically, CMOS input thresholds require high-level signals to be at least 70% of Vcc and low-level signals to be at most 30% of Vcc. (TTL has the input high level above 2.0 V and the input low level below 0.8 V, so a TTL high-level signal could be in the forbidden middle range for 5 V CMOS.)
The following is a list of CMOS 4000-series digital logic integrated circuits.In 1968, the original 4000-series was introduced by RCA.Although more recent parts are considerably faster, the 4000 devices operate over a wide power supply range (3V to 18V recommended range for "B" series) and are well suited to unregulated battery powered applications and interfacing with sensitive analogue ...
HCMOS ("high-speed CMOS") is the set of specifications for electrical ratings and characteristics, forming the 74HC00 family, a part of the 7400 series of integrated circuits. [ 1 ] The 74HC00 family followed, and improved upon, the 74C00 series (which provided an alternative CMOS logic family to the 4000 series but retained the part number ...