74AS00 Quad 2-Input NAND Gate. Physical Dimensions inches (millimeters) unless otherwise noted (Continued). Lead Plastic Dual-In-Line Package ( PDIP). 74AS00 Datasheet, 74AS00 PDF, 74AS00 Data sheet, 74AS00 manual, 74AS00 pdf, 74AS00, datenblatt, Electronics 74AS00, alldatasheet, free, datasheet. description. These devices contain four independent 2-input positive-NAND gates. They perform the Boolean functions Y = A • B or Y = A + B in positive logic.
To give students a sense of the magnitudes of voltage, current, resistance, capacitance, time, frequency, etc. In this diagram, observe that the output stage consists of two active elements, Q3 and Q4. Draw the input and output waveforms timing diagram. Observe here that the circuit elements associated with Q4 in the totem-pole circuit are missing and the collector of Q3 is left open-circuited, hence the name open-collector.
What is the difference between open collector, tri-state and totem-pole outputs? What happens when the outputs of two totem-pole outputs are connected together? Datasheeet is the diference between a inverter and a Schmitt trigger? To present basic characteristic and limitations of gates. Let us examine the typical totem-pole output once again. Conversely, when Q3 is open, Q4 is closed. What is the voltage range that would be considered a logic LO?
(PDF) 74AS00 Datasheet PDF Download – Quadruple 2-Input Positive-NAND Gates
Datsheet a 1K potentiometer to supply a variable input voltage. What is the range that would be considered a logic HI?
Measure both the input voltage and the logic output of the inverter. Problem 11 – Monostable Multivibrator The circuit shows one-half of a 74LS dual “one-shot” monostable multivibrator being used to generate a pulse of adjustable width. Digital logic is implemented using integrated circuits which are classified into families based on their basic electronic structure. What is meant by tri-state or 3-state outputs? In contrast with a normal totem-pole output, it cannot be the source of current and therefore cannot present a logic-HI on its own.
Where would you use the latter instead of the former? What is the maximum current flowing through the outputs in c? At any time, only one of the two switches is closed while the other is open.
The tri-state bus datashete has an enable input G. Digital IC manufacturers are continually trying to minimize the delay-power product and continue to produce families with different characteristics to suit specific needs. What is the lowest value of R such that the output is still HI?
Study the feedback circuits shown and use the oscilloscope to examine the signal at different stages in the circuit. This is called the high impedance or Hi-Z state.
Regardless of the IC’s complexity or how it is created, basic knowledge of gates and flip-flops is still essential. Problem 7 – Schmitt trigger oscillator Construct this simple oscillator and measure the frequency of oscillation for a given R and C.
When and why would you use tri-state and open-collector outputs as opposed to totem-pole outputs? Construct the circuit shown and study how the frequency and duty cycle are affected by R2 and C. All simulation and debugging is conducted on the computer before the chip is created.
Complex electronic circuits for high volume production are produced today using ASICs application specific ICs compiled entirely using a computer-aided design CAD system. Calculate the range of values for this resistor. When G is LO, the output is in the high impedance state. Problem 8 – Timer The timer IC is a popular circuit for generating asymmetric rectangular waves. Also shown in Figure 6. Using a very high frequency clock input measure the propagation delay of a typical 74xx or 74LSxx TTL gate.
In normal usage a logic-HI is provided by an external pull-up resistor as shown.
(PDF) 74AS00 Datasheet download
An open-collector output has current sinking capabilities, that is, it can present a datasheeet output. This third state is a useful feature and is employed in tri-state outputs as another way of creating party-line bus systems.
Measure the voltage present at the input pin when no connection is made to it.
This is useful for creating a party-line data bus or control bus whereby any one of several circuits may pull the line LO without causing damage to another active output. In other words, when Q3 is closed, Q4 is open.
If you examine a typical circuit board today you will dataxheet more use of large ICs with hundreds of pins and fewer style ICs. What is the meaning of hysteresis? The chart shows the speed-power relationship of common TTL families. What is the smallest value of R such that the output is still LO?
Families can be characterized by the relationship between propagation-delay and power. The following table dstasheet a growing list of various sub-families with their characteristics and designations. What is the input hysteresis in volts for these two gates?
Within the TTL family, there are many second-generation families, each with different operating characteristics. Why is negative logic commonly used? Two important factors in the consideration of each logic family are speed and power consumption.
The final chip may either be burned on the spot using a programmable logic array PLA or may be produced in higher volumes by the IC manufacturer. Analyze the circuits and explain datasheeh results.