Search results
Results from the WOW.Com Content Network
Often two level shifters are used, one at each system: A line driver converts from internal logic levels to standard interface line levels; a line receiver converts from interface levels to internal voltage levels. For example, TTL levels are different from those of CMOS. Generally, a TTL output does not rise high enough to be reliably ...
A TTL input signal is defined as "low" when between 0 V and 0.8 V with respect to the ground terminal, and "high" when between 2 V and V CC (5 V), [22] [23] and if a voltage signal ranging between 0.8 V and 2.0 V is sent into the input of a TTL gate, there is no certain response from the gate and therefore it is considered "uncertain" (precise ...
This problem was solved by the invention of the 74HCT family of devices that uses CMOS technology but TTL input logic levels. These devices only work with a 5V power supply. They form a replacement for TTL, although HCT is slower than original TTL (HC logic has about the same speed as original TTL).
Although the 7400 series was the first de facto industry standard TTL logic family (i.e. second-sourced by several semiconductor companies), there were earlier TTL logic families such as: Sylvania Universal High-level Logic in 1963 [8] [9] [10] Motorola MC4000 MTTL [11] [12] [13] National Semiconductor DM8000 [14] [better source needed]
In digital electronics, a level shifter, also called level converter or logic level shifter, or voltage level translator, is a circuit used to translate signals from one logic level or voltage domain to another, allowing compatibility between integrated circuits with different voltage requirements, such as TTL and CMOS.
A five level PAM digital signal. In digital electronics, a digital signal is a pulse amplitude modulated signal, i.e. a sequence of fixed-width electrical pulses or light pulses, each occupying one of a discrete number of levels of amplitude. [6] [7] A special case is a logic signal or a binary signal, which varies between a low and a high ...
As semiconductor technology has progressed, LVCMOS power supply voltage and interface standards for decreasing voltages have been defined by the Joint Electron Device Engineering Council for digital logic levels lower than 5 volts.
Digital electronics circuits operate at fixed voltage levels corresponding to a logical 0 or 1 (see binary). An inverter circuit serves as the basic logic gate to swap between those two voltage levels. Implementation determines the actual voltage, but common levels include (0, +5V) for TTL circuits.