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All standard TTL devices use a two transistor "totempole" output, one transistor provides an active pull down and the other an active pull up. Only one of these transistors is on at a time and one or the other is always on.
Open collector TTL devices omit the active pull up transistor so that several outputs can be "wired" together and an external resistor provides a passive pull up. The only problem with this is the risetime of a passive pullup is much longer than the risetime of an active pull up, making the circuit slower.
Tristate TTL devices have the same two transistor "totempole" output as standard TTL devices, but the circuits that control these transistors are more complex allowing a "third state" in which both transistors are turned off, leaving the output of the device floating. This allows many tristate TTL devices to be connected to a single line with only one actually driving it at a time (preventing conflicts with one device pulling up and another pulling down).
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What type of gate is the 74LS00?
The 74LS00 is a quad two input NAND gate with low power schottkey TTL implementation.
What is the IC number for 3-input nand gate?
TTL 7410CMOS 4023DTL 962/C
How NAND gate works?
A: NAND implies not and to be true both input must be hi or true <> There are two flavors of NAND gate. The positive input/negative output NAND will have a low output if and only if both inputs are high. The negative input/positive output NAND will have a high output if and only if both inputs are low.
What is the Use of 7408 IC?
a 7408 ic chip is a quadruple, 2 input AND Gate chip. These chips have 14 pins. Pin 7 is gnd and pin 14 is vcc. In principle, an AND Gate is just that. A gate that is Active high. To get an active high output, you must have both inputs active high. 5 volts on each input will give you a 5 volt output. These IC chip use TTL (transistor-transistor logic). They are obsolete and are no longer used in todays electrical circuits. Most electronic systems use a large CPLD, Complex Programmable Logic Device, that can be used to implement digital logic designs that contain 20,000 or fewer gates. Texas Instruments poineered the TTL 7408 IC chip. CPLD boards are commonly made by a company named Altera
The main advantage of ECL over TTL?
The main advantage of ECL over TTL is speed.
Ttl nand gate?
The TTL Nand gate is usually used in the design of various electric circuits.
Explain working of ttl for NAND gate?
In the NAND gate, the transistors play the role of the switches. The emitter and the collector voltages vary in the opposite phase.
What type of gate is the 74LS00?
The 74LS00 is a quad two input NAND gate with low power schottkey TTL implementation.
What is the IC number for 3-input nand gate?
TTL 7410CMOS 4023DTL 962/C
How NAND gate works?
A: NAND implies not and to be true both input must be hi or true <> There are two flavors of NAND gate. The positive input/negative output NAND will have a low output if and only if both inputs are high. The negative input/positive output NAND will have a high output if and only if both inputs are low.
What are the characteristics of ttl nand gate?
A: It is simply a function of negating a true input, the other characteristics s that it is limited in fan-in fan -out capabilities
Why is a TTL logic gate faster than a CMOS logic gate?
The switching time (on and off) of the TTL logic gate is very fast in comparison with CMOS logic gate. However, they could not tolerate higher range of power supply.
What is 7432 ic?
The 7432 is a quad two input OR gate with TTL levels.
Ic number of or gate?
Ttl: 7432, 744075cmos: 4071
What is the function of 74LS08?
74LS08 is a quad two-input AND gate with LS-TTL logic levels.
What is the Ic number of 8 input x-or gate?
TTL 74 86 series or CMOS 4030
Why an open ttl gate behaves as a logic high input?
because TTL have a bias input setup to eliminate noise therefore the output will follow the logic one input if left open
