O circuito lógico TTL é um dispositivo TTL que possui quatro portas lógicas AND de duas entradas cada porta. Ele é usado, principalmente, em circuitos. jpg ( × pixels, file size: 15 KB, MIME type: image/jpeg). Open in Media English: chip Date, 14 Circuito integrado Utilice dos CI y un CI Contador decimal Esto se hace iniciando el circuito con cada uno de los seis estados no utilizados mediante las entradas de .

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As the reverse-bias potential increases in magnitude the input capacitance Cibo decreases Fig. For this particular example, the calculated percent deviation falls well within the permissible range. There will be a change of VB and VC for the two stages if the two voltage divider B configurations are interchanged.

This range includes green, yellow, and orange in Fig. Events repeat themselves after this.

Construção de um modelo computacional para o circuito de ventilação da Mina Esperança

See circuit diagram above. Such may not be entirely true. Computer Exercises Pspice Simulations 1. For voltage divider-bias-line see Fig. The percent differences are determined with calculated values as the reference. It is essentially the reverse saturation leakage current of the diode, comprised mainly of minority carriers. The voltage-divider configuration is the least sensitive with the fixed-bias configuration very sensitive.

No VPlot data 1. The LCD, however, requires a light source, either internal or external, and the temperature range of the LCD is limited to temperatures above freezing. While in the former case the voltage peaked to a positive 3.


For either Q1 or Q2: Common-Emitter DC Bias b. Experimental Determination of Logic States. Y is identical to that of the TTL clock.

The voltage divider bias line is parallel circiuto the self-bias line. The IS level of the germanium diode is approximately times as large as that of the silicon diode.

In addition, the drain current has reversed direction. Majority carriers are those carriers of a material that far exceed the number of any other carriers in the material. Both capacitances are present in both the reverse- and forward-bias directions, but the transition capacitance is the dominant effect for reverse-biased diodes and the diffusion capacitance is the dominant effect for forward-biased conditions.

The levels are higher for hfe but note that VCE is higher also.


Example of a calculation: V1 12 V The voltage of the TTL pulse was 5 volts. Parallel Clippers continued b. The voltage-divider bias configuration was the least sensitive to variations in Beta.

All the circuit design does is to minimize the effect of a changing Beta in a circuit. To shift the Q point in either direction, it is easiest to adjust the bias voltage VG to bring the circuit parameters within an acceptable range of the circuit design. Logic States versus Voltage Levels a. All the contents of this journal, except where circyito noted, is licensed under a Creative Commons Attribution License.


Silicon diodes also have a higher current handling capability. Maintain proper bias across Q1 and Q2. This seems not to be the case in actuality. The voltage level of the U2A: Thus in our case, the geometric averages would be: They are the same.


Computer Exercise PSpice Simulation 1. Beta did increase with increasing levels of IC. Threshold Voltage VT Fig 3. Their shapes are similar, but for a given ID, the potential VD is greater for the silicon diode compared to the germanium diode. Thus, Cicruito is considerably reduced.

The right Si diode is reverse-biased. This is expected since the resistor R2, while decreasing the current gain of the circuit, stabilized the circuit in regard to any current changes.

Both intrinsic silicon and germanium have complete outer shells due to the sharing covalent bonding of electrons between atoms. Ge typically has a working limit of about 85 degrees centigrade while Si can be used at temperatures approaching degrees centigrade. V 1, 2 remains at 2 V during the cycle of V 1 6. The design and efficiency analysis in a ventilation circuit can be carried out using Hardy Cross algorithm and Kirchhoff law.

For a more detailed analysis or checking the effect in the ventilation circuit due to mining changes, computational simulation can be used. From problem 14 b: It is to be noted however that with such small values the difference in just one ohm manifests itself as a large percent change. VO calculated is close circuio V 2 of Probe plot.