PROJECT

ELECTRONIC CIRCUITS

DIGITAL PULSE COUNTER

PRESENTED BY:-

PRATIBHA PAL: U10EC088

BHOOMIKA PATEL: U10EC089

RITIKA CHAWLA: U10EC114

Digital Pulse Counter -

Single Digit   .In this project you will get experience with using seven segment LED display and Counter and display decoder. The project uses a single common cathode 7 segment display that will display the count up to 9. The IC used for counting is IC 4026 which also comes with display driver. The IC counts the pulses and converts that to a decimal number up to 9 and supplies power to the appropriate segments of the display to show the current count. when the count reaches 9 it will be reset back to zero and continues again. 

Pulses used for counting can be manually supplied by touching the +ve and -ve terminals or can be fed from any other source. In this project we use a 555 timer to feed the pulses. 

Below is the circuit used to build the counter.

Elements used:-

LIST OF PARTS USED IN THE PROJECTREF PART TYPE PART NAME VALUE COUNT 7 Seg1 DISPLAY Seven Segment Display 14 mm -- 1 Bat1 BATTERYPACK Battery Pack 6V AA -- 1 C1 ELECCAPACITOR Electrolytic Capacitor 10uF 10uF 1 IC1 IC IC NE555 NE555 1 IC2 IC IC 4026 4026IC 1 R1 RESISTOR Resistor 10K 10K 1 R2 POT Pot Meter 100K 100K 1

Seven Segment Display 14 mm

A seven segment display, as its name indicates, is composed of seven elements. Individually on or off, they can be combined to produce simplified representations of the arabic numerals. Often the seven segments are arranged in an oblique (slanted) arrangement, which aids readability. In most applications, the seven segments are of nearly uniform shape and size (usually elongated hexagons, though trapezoids and rectangles can also be used), though in the case of adding machines, the vertical segments are longer and more oddly shaped at the ends in an effort to further enhance readability.

Each of the numbers 0, 6, 7 and 9 may be represented by two or more different glyphs on seven-segment displays.

The seven segments are arranged as a rectangle of two vertical segments on each side with one horizontal segment on the top, middle, and bottom. Additionally, the seventh segment bisects the rectangle horizontally. There are also fourteen-segment displays and sixteen-segment displays (for fullalphanumerics); however, these have mostly been replaced by dot-matrix displays.

The segments of a 7-segment display are referred to by the letters A to G, as shown to the right, where the optional DP decimal point (an "eighth segment") is used for the display of non-integer numbers.

Numbers to 7-segment-codeA single byte can encode the full state of a 7-segment-display. The most popular bit encodings are gfedcba and abcdefg - both usually assume 0 is off and 1 is on.

Implementations

An incandescent light type early

seven-segment display

A mechanical seven-segment

display for

displayingautomotive fuel prices

Seven-segment displays may use a liquid crystal display (LCD), arrays of light-emitting diodes (LEDs), or other light-generating or controlling techniques such as cold cathode gas discharge, vacuum fluorescent, incandescent filaments, and others. For gasoline price totems and other large signs, vane displays made up of electromagnetically flipped light-reflecting segments (or "vanes") are still commonly used. An alternative to the 7-segment display in the 1950s through the 1970s was the cold-cathode, neon-lamp-like nixie tube. Starting in 1970, RCA sold a display device known as the Numitron that used incandescent filaments arranged into a seven-segment display.

In a simple LED package, typically all of the cathodes (negative terminals) or all of the anodes (positive terminals) of the segment LEDs are connected and brought out to a common pin; this is referred to as a "common cathode" or "common anode" device. Hence a 7 segment plus decimal point package will only require nine pins (though commercial products typically contain more pins, and/or spaces where pins would go, in order to match industry standard pinouts).

Integrated displays also exist, with single or multiple digits. Some of these integrated displays incorporate their own internal decoder, though most do not – each individual LED is brought out to a connecting pin as described. Multiple-digit LED displays as used in pocket calculators and similar devices used multiplexed displays to reduce the number of IC pins required to control the display. For example, all the anodes of the A segments of each digit position would be connected together and to a driver pin, while the cathodes of all segments for each digit would be connected. To operate any particular segment of any digit, the controlling integrated circuit would turn on the cathode driver for the selected digit, and the anode drivers for the desired segments; then after a short blanking interval the next digit would be selected and new segments lit, in a sequential fashion. In this manner an eight

digit display with seven segments and a decimal point would require only 8 cathode drivers and 8 anode drivers, instead of sixty-four drivers and IC pins. Often in pocket calculators the digit drive lines would be used to scan the keyboard as well, providing further savings; however, pressing multiple keys at once would produce odd results on the multiplexed display.

Seven segment displays can be found in patents as early as 1908 (in U.S. Patent 974,943, F W Wood invented an 8-segment display, which displayed the number 4 using a diagonal bar), but did not achieve widespread use until the advent of LEDs in the 1970s. They are sometimes even used in unsophisticated displays like cardboard "For sale" signs, where the user either applies color to pre-printed segments, or (spray)paints color through a seven-segment digit template, to compose figures such as product prices or telephone numbers.

For many applications, dot-matrix LCDs have largely superseded LED displays, though even in LCDs 7-segment displays are very common. Unlike LEDs, the shapes of elements in an LCD panel are arbitrary since they are formed on the display by a kind of printing process. In contrast, the shapes of LED segments tend to be simple rectangles, reflecting the fact that they have to be physically moulded to shape, which makes it difficult to form more complex shapes than the segments of 7-segment displays. However, the high common recognition factor of 7-segment displays, and the comparatively high visual contrast obtained by such displays relative to dot-matrix digits, makes seven-segment multiple-digit LCD screens very common on basic calculators.

Battery Pack 6V AA

A primary cell is any kind of battery in which the electrochemical reaction is not reversible, rendering the cell unrechargeable. A common example of a primary cell is the disposable battery. Unlike a secondary cell, the reaction cannot be reversed by running a current into the cell; the chemical reactants cannot be restored to their initial position and capacity. Primary batteries use up the materials in one or both of their electrodes

Electrolytic Capacitor 10uF

An electrolytic capacitor is a type of capacitor that uses an electrolyte (an ionic conducting liquid) as one of its plates to achieve a largercapacitance per unit volume than other types, but with performance disadvantages. All capacitors conduct alternating current (AC) and blockdirect current (DC) and can be used, amongst other applications, to couple circuit blocks allowing AC signals to be transferred while blocking DC power, to store energy, and to filter signals according to their frequency. The large capacitance of electrolytic capacitors makes them particularly suitable for passing or bypassing low-frequency signals and storing large amounts of energy. They are widely used in power supplies and for decoupling unwanted AC components from DC power connections.

Supercapacitors provide the highest capacitance of any practically available capacitor[1], up to thousands of farads, with working voltages of a few volts. Electrolytic capacitors range downwards from tens (exceptionally hundreds) of thousands of microfarads to about 100 nanofarads—smaller sizes are possible but have no advantage over other types. Other types of capacitor are available in sizes typically up to about ten microfarads, but the larger sizes are much larger and more expensive than electrolytics (film capacitors of up to thousands of microfarads are available, but at very high prices[2]). Electrolytic capacitors are available with working voltages up to about 500V, although the highest capacitance values are not available at high voltage. Working temperature is commonly 85°C for standard use and 105° for high-temperature use; higher temperature units are available, but uncommon.

Unlike other types of capacitor, most electrolytic capacitors require that the voltage applied to one terminal (the anode) never become negative relative to the other (they are said to be "polarized"), so cannot be used with AC signals without a DC polarizing bias (non-polarized electrolytic capacitors are available for special purposes).

Leakage current, capacitance tolerance and stability, equivalent series resistance (ESR) and dissipation factor are significantly inferior to other types of capacitor, and working life is shorter. Capacitors can lose capacitance as they age and lose electrolyte, particularly at high temperatures. A common failure mode which causes difficult-to-find circuit malfunction is progressively increasing ESR without change of capacitance, again particularly at high temperature. Large ripple currents flowing through the ESR generate harmful heat.

Two types of electrolytic capacitor are in common use: aluminum and tantalum. Tantalum capacitors have generally better performance, higher price, and are available only in a more restricted range of parameters. Solid polymer dielectric aluminum electrolytic capacitors have better characteristics than wet-electrolyte types—in particular lower and more stable ESR and longer life—at higher prices and more restricted values.

IC NE555

The 555 timer IC is an integrated circuit (chip) used in a variety of timer, pulse generation, and oscillator applications. The 555 can be used to provide time delays, as an oscillator, and as a flip-flop element. Derivatives provide up to four timing circuits in one package.

Introduced in 1971 by Signetics, the 555 is still in widespread use, thanks to its ease of use, low price and good stability, and is now made by many companies in the original bipolar and also in low-power CMOS types. As of 2003, it was estimated that 1 billion units are manufactured every year.

The IC was designed in 1971 by Hans R. Camenzind under contract to Signetics, which was later acquired by Philips.

Depending on the manufacturer, the standard 555 package includes 25 transistors, 2 diodes and 15 resistors on a silicon chip installed in an 8-pin mini dual-in-line package (DIP-8).[2]Variants available include the 556 (a 14-pin DIP combining two 555s on one chip), and the two 558 & 559s (both a 16-

pin DIP combining four slightly modified 555s with DIS & THR connected internally, and TR is falling edge sensitive instead of level sensitive). There is no 557.

The NE555 parts were commercial temperature range, 0 °C to +70 °C, and the SE555 part number designated the military temperature range, −55 °C to +125 °C. These were available in both high-reliability metal can (T package) and inexpensive epoxy plastic (V package) packages. Thus the full part numbers were NE555V, NE555T, SE555V, and SE555T. It has been hypothesized that the 555 got its name from the three 5 kΩ resistors used within, but Hans Camenzind has stated that the number was arbitrary.

Low-power versions of the 555 are also available, such as the 7555 and CMOS TLC555.The 7555 is designed to cause less supply noise than the classic 555 and the manufacturer claims that it usually does not require a "control" capacitor and in many cases does not require a decoupling capacitor on the power supply. Such a practice should nevertheless be avoided, because noise produced by the timer or variation in power supply voltage might interfere with other parts of a circuit or influence its threshold voltages.

IC 4026

The 4000 series is a family of industry standard integrated circuits which implement a variety of logic functions using Complementary Metal–Oxide–Semiconductor technology, and are still in use today. They were introduced by RCA as CD4000 COS/MOS series in 1968, as a lower power and more versatile alternative to the 7400 series of TTL logic chips.Almost all IC manufacturers active

during the era fabricated chips from this series. RCA sometimes advertised the line as COSMOS, standing for COmplementary Symmetry Metal-Oxide Semiconductor. The naming system followed the RCA convention of CA for analog, CD for digital, but did not relate to the Texas Instruments SN7400 series numbering scheme.

4000 series parts had the advantage of lower power consumption, wider range of

supply voltages (3 V to 15 V), and simpler circuit design due to the vastly increased fanout. However

their slower speed (initially about 1 MHz operation, compared with bipolar TTL's 10 MHz) limited their

applications to static or slow speed designs. Later, new fabrication technology largely overcame the

speed problems, while retaining backward compatibility with most circuit designs. Although all

semiconductors can be damaged by electrostatic discharge, the high impedance of CMOS inputs

makes them more susceptible than bipolar transistor-based, TTL, devices. Eventually, the advantages

of CMOS (especially the later series such as 74HC) edged out the older TTL chips, but at the same

time ever increasing LSI techniques edged out the modular chip approach to design. The 4000 series

is still widely available, but perhaps less important than it was two decades ago.

The series was extended in the late 1970s and 1980s to include new types which implemented new functions, or were better versions of existing chips in the 4000 series. Most of these newer chips were given 45xx and 45xxx designations, but are usually still regarded by engineers as part of the 4000 series.

In the 1990s, some manufacturers (e.g. Texas Instruments) ported the 4000 series to their newer HCMOS technology with devices such as the 74HCT4060 providing equivalent functionality to a 4060 IC but with greater speed.

Resistor 10K

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's terminals to the intensity of current through the circuit is called resistance. This relation is represented by Ohm's law:

where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms. More specifically, Ohm's law states that the R in this relation is constant, independent of the current. Resistors are common elements of electrical networks and electronic circuits and are ubiquitous in electronic equipment. Practical resistors can be made of various compounds and films, as well as resistance wire (wire made of a high-resistivity alloy, such as nickel-chrome). Resistors are also implemented within integrated circuits, particularly analog devices, and can also be integrated into hybrid and printed circuits.

The electrical functionality of a resistor is specified by its resistance: common commercial resistors are manufactured over a range of more than nine orders of magnitude. When specifying that resistance in an electronic design, the required precision of the resistance may require attention to the manufacturing tolerance of the chosen resistor, according to its specific application. The temperature coefficient of the resistance may also be of concern in some precision applications. Practical resistors are also specified as having a maximum power rating which must exceed the anticipated power dissipation of that resistor in a particular circuit: this is mainly of concern in power electronics applications. Resistors with higher power ratings are physically larger and may require heat sinks. In a high-voltage circuit, attention must sometimes be paid to the rated maximum working voltage of the resistor.

Practical resistors have a series inductance and a small parallel capacitance; these specifications can be important in high-frequency applications. In a low-noise amplifier or pre-amp, the noise characteristics of a resistor may be an issue. The unwanted inductance, excess noise, and temperature coefficient are mainly dependent on the technology used in manufacturing the resistor. They are not normally specified individually for a particular family of resistors manufactured using a particular technology.[1] A family of discrete resistors is also characterized according to its form factor, that is, the size of the device and the position of its leads (or terminals) which is relevant in the practical manufacturing of circuits using them.

Pot Meter 100K

A potentiometer informally, a pot, in electronics technology is a component, a three-terminal resistor with a sliding contact that forms an adjustable voltage divider.[1] If only two terminals are used, one end and the wiper, it acts as a variable resistor or rheostat.

In circuit theory and measurement a potentiometer is essentially a voltage divider used for measuring electric potential (voltage); the component is an implementation of the same principle, hence its name.

Potentiometers are commonly used to control electrical devices such as volume controls on audio equipment. Potentiometers operated by a mechanism can be used as position transducers, for example, in a joystick.

Potentiometers are rarely used to directly control significant power (more than a watt), since the power dissipated in the potentiometer would be comparable to the power in the controlled load (see infinite switch). Instead they are used to adjust the level of analog signals (e.g. volume controls on audio equipment), and as control inputs for electronic circuits. For example, a light dimmer uses a potentiometer to control the switching of a TRIAC and so indirectly to control the brightness of lamps.

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