High-impedance state; What is a tri-state gate? Three-state logic and non-gate circuit and three-state gate circuit

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High-impedance state: is neither higher nor low, if the high impedance state and then input the next level of the circuit, no impact on the lower circuit, and not the same, if using a multimeter is likely to be high level also may be low level, with the things that follow it fixed.

Tri-State output gate Circuit ( TS(three-state output gate) Door

the schematic diagram of the three-state gate output gate circuit. In the figure, if the two inverter and a diode inside the dashed box are cut off, the remainder is the typical TTL and non-gate circuitry .

the so-called Tri-state refers to the output . Ordinary TTL and non-gate its output pole of two transistors T4,T5 always maintain one conduction, the other cut off the push-pull state. T4 conduction,T5 cutoff, output high level Y=1,T4 Cutoff,T5 conduction, output low level,y=0. Three-state gate in addition to the above two states, there are T4,T5 and The third State of the cutoff. Because the transistor cut -off time between C,e is an infinite impedance, the output Y to ground, the power supply (VCC) Impedance infinity. Therefore this third State is also called the high-impedance state.

High-impedance state; What is a tri-state gate? Three-state logic and non-gate circuit and three-state gate circuit