Microcontroller Based Object Counter

Project code:- E43 Project Cost:- INR:- Rs. 3000/- USD:- 75$




The project presented here is based on world’s most powerful microco-ntroller based on intel’s mcs-51 family , generally known as intel-8051. We have used its derivative atmel-89c2051.


Object Counter Block Diagram 

Operation: A pair of 38khz transmitter and a receive is used to count the objects. Counts pulses are out from the 38khd receiver which are coupled to an opto coupler. At pin 2 out put of the optocoupler is connected to microcontroller pin 8 p3.4.

Ic3 an optocoupler will receive incoming count pulse at pin3 and output from pin 5 is connected to p3.4 pinof the ic2 microcontroller,

Two line by 16 character on each line (2×16) is used in nibble mode and maximun count can reach upto 65536 there after it will reset to 00000.

SW1 is manual reset switch to make the counter to reset to zero.

Circuit is driven by 9v 500m.a. transformer connected to PCON1

Diode D1-D4 forms bridge circuit C1,c2 and c3 are filter capacitors and are part of power supply section..

Ic1 7805 is 5v regulator ic to give stablised supply to microcontroller. Ld1 is a power indication led. R1 controls the current flowing thrugh led LD1 Crystal X1 along with C5 and C6 gives the necessary clock to microcontroller.

Capacitor C4 and R2 gives the required reset pulse to microcontroller

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Industrial Automation & Monitoring System

Project code:- E63 Project Cost:- INR:- Rs. 12000/- USD:- 300$

The mentioned project is based on the world,s most powerful intel controller 8051. most of the services provided in todays world are voice interactive, you call up your bank and computrised voice will speak to you,and guide you to enter a particular number from your phone to get the desired service.this service is only available through the fast speed computers and having huge ammount of memory.we emplemented interactive service for industrial applications.

you can switch on/off devices using your mobile phone or land line phone five numbers loads can be connected to the five relay provided.not only you can switch on /off devices it will also dial out a telephone number in case of security threat,or any safety or protection parameters goes beyond safety limit. in case of any of the above , for ex. temperature of the machinery has gone beyond safety limit ,the device will first switch off the plant and dials out the pre-stored telephone number and delivers the emergency message. it will dial out foe five times at the interval of one minute and again monitor the parameters, and if the parameters are not within limit again it will dial out . this cycle will repeat until the parameters becomes normal.
application: this project could be used for variety of purpose where you want to control something remotely.

a) suppose you own a company and are three or more partners and are always traveling. you have an office located some where. and have a main server you do not want that somebody other then your partner should handle this server due to security reason. at the same time you do not want to keep your server all the time on so there this device comes to your help only requirement for this device is a parallel telephone connection.and of course power supply.you can switch on your server remotely from any where in the world. when you dial the number where this device is connected with the server,after five number of bell ringing you will hear please enter your password. when you enter the password. if your password is correct then device will further respond otherwise without giving any further response device will disconnect you.if you number is correct you will receive these message
press one for normal on off, press two for password change press three for telephone number change, press star to listen this menu again.
so if you press 1 and 1&1 you get message requested channel is on or 1&0 requested channel is off 1&2 to now the status of previously on or off channels similarly with all the five channels same combination are applies you can press star(*) to go back to previous menu.
now pressing two you can change the password and device will respond like this please enter your password and your password has been changed. similarly by pressing three you can change telephone number.and device will respond please enter new telephone number &your telephone number has been changed.

b) This was one example of this device similarly this could be used to control or switch on any process control machionary where allfunctions are automatic. electric grid could be controlled remotely. or outomatic production machionery could be controlled even during odd hours with yiur mobile phone.
security features of this device suppose there is fire at the machionery space this device will switch off the machionery first and the dial our the pre stored number to your phone and will deliver the emergency message. and will keep dialing untill you come and personally reset this device.
this device has the following blocks

1. ring detector circuit comprises of bridge rectifire d1-d4 and opto coupler u8 mct2e
2. watch dog timer comprising of ic 7400 and u7 ic 4047
3. dtmf decoder ic u6 8870
4. dialer circuit relay rl2 transister q1
5. off hook circuit relay rl1 and transformer tr1 c5 and r8.
6. microcontroller circuit the central processor 89c51
7. speech circuit ic uv1 1840 where all the messages are stored
8. amplifire circuit ic uv2 lm 386
9. security storage ic 93c46
10. and load controller where relay boards will be connected p1
11. power supplay circuit ic u10 7805,bridge rectifires d1-d4
12. capacitor c1 and c2
13. fire sensor is connected to connector p2 connector

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Automatic Toll Tax

Project code:- E23 Project Cost:- INR:- Rs.12000/- USD:- 300$

Automatic toll tax project is designed ,using atmel 89c51 microcontroller & descreate componants. Heart of the project is an ir transmitter and receiver modules ,these strong powerfull modules transmits 38khz strong ir beam, has a range of more than 15 feets are sufficiently enough for our project. I have designed this project as a simple emplementation of the toll collection process automatically in a model form.

Automatic Toll Tax With Block Diagram 

Automatic Toll Tax Representation 
Project Video

This should not be considered as a real toll collection system which require much more considerations , tests and huge amount of money, before they are actually put into use.
However this project gives enough guidelines for the actual dvelopment of the toll collection system. For the sake of simplicity , we have to make coin box exactly same as used in pco coin box machine fixed on railway station or else whare. We have to make two coin size holes one for one rupee, and other for five rupee coin. You have to fixup coin sensors on these holes, one sensor should be fixed for five rupee coin and one sensor for one rupee coin.
Operation of the coin sensor is as follows
1) When no coin is incerted light emitting diodes throws light on ldr and its resistance remains low
2) When coin is inserted,the resistance of the ldr becomes high and transister(q1 or q2) get enough biasing voltage and becomes ON ,there output at collector becomes low. As the coin is dropped in,,the out put of the collector again goes high,
3) Output of these transisters are connected to p2.5 and p2.7 pin of the microcontroller and low pulse is detected by the microcontroller whenever the coin is dropperd
This low pulse detection is considered as coin has been dropped.
In real emplementation, this type of sensors cannot be used ,more sensitive equipments such as coin changers,or currency emaging machines shuld be employed . Some of them you will find on railway stations or out side temples.

Port 1 is connected with the 2 line 16 character lcd. lcd is used in nibble mode
Port 0 is used as output port used for gate motor and indication leds
Ic 3 api 89021 is one time programmable (otp) speech ic where our message is stored. It is addressable ic so required message can be played.
Ic4 Lm 386 is used as audio amplifire ic to drive the speaker
Ic1 7805 is regulator ic gives 5v regulated power supply to the entire circuit.
Ir transmittrs are mounted on a pole at different heights matching to the heights of small and heavy vehicles. Similarly receivers are mounted on the other side of the road at the corresponding heights of transmitters.One pair of transmitter and receivers are to be mounted across the road afrer 15/20 feet of the toll station. Please see the video for
Arrangements of transmitter and receiver arrangements.

Operation: when heavy veichel passes the output of hvrx receiver becomes low and makes the p2.1 pin low microcontroller understand that heavy veichel is passed, p3.7 will go high which will trigger the pin no 10 of ic api 89021 and sound ‘pl enter 5 rs coin’ will come out through pin no 7 of the ic and is connected to c10 vr2 volume control and to

the pin no 3 of ic lm386. Audio can be heard through speaker. At the same time p0.2 will also go high and led ld3 rs 5 indication will come on
when the user inserts rs 5 coin, p2.7 pin will get low going pulse and rs 5 indication led will go off, also the sound will stop and gate motor will operate in the open direction.by p0.0.
When the veichele passes through outer sensor area out put of outrx will give low pulse at p2.3 and gate will close by p0.1 The circuit is ready for the next operation. Similarly when small veichele croses, lvrs will get activated and p2.2 will get low going pulse and p3.6 will become high and make pin no 11 of api89021 will go high ind sound will come’ pl enter one rs coin’ also ld2 ,one rupee coin will become on by p0.3 .other operation are similar .

Lcd keeps the counter of heavy and small veichles Circuit operates on 12v ac supply given at ac input point pcon 1. 9 v one amp. Transformer is connected to pcon1 bridge rectifire circuit d1-d4 ,c1 ic 7805 gives the regulated power supply. Ic5 connected on port 0. 74LS 245 is used as buffer ic to make the output current strong q3,q4,q5 and q2 transister operates the relay circuit to drives the motor .Motor runs in one direction for opening the gate and in opposite direction for closing the gate.

Source: Click here

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Mobile Phone Operated Buggie / Robot

Project code:- E42 Project Cost:- INR:- Rs.7500/- USD:- 200$

Now my young buggie has grown to maturity and can be contacted over mobile phone . designed for various applications . This buggie is opeaed by DTMF codes which it listens through it’s ear circuit connected to mobile phone. It obeys all the required commands sent by the master, have complete function like car. From the remote location you can send the buggie where humen entry is not possible.


mobile operated robot / buggie Block Diagram 

Places like neuclear radiation effected area ,dangerous gas effected area, between narrow spaces, reactor inspection. And many more place This can be used as
1.Spy robot (if camera is installed on it)
2. Fire fighting
3.Spray painting
4.Fumigation
5.Pesticide spraying
6.Gas leakage detection
7.Drilling
8.Metel detection
9. Mine sweeping
10.Sample collection and many more…….
You need to install the required apparatus on this buggie to do your job.
Note:This is a simple model. Professional equipments should be developed on these guidelines
To carry out above operations.

DTMF – HOW DOES IT WORK

DTMF was originally developed to allow sending control information (dialled numbers) across the telephone network. The telephone network has a bandwidth of approx. 300 to 3400 Hz, suitable for voice communications. Any control tones would also need to be in this range and had to work regardless of whether voice was present or not.

A single tone or frequency could have been used. However, if voice was present, it would interfere with the control tones, making them useless. To overcome this a scheme was developed where by two tones or frequencies were combined to represent each control code or number.

A total of seven tones were needed to represent the digits normally found on a telephone keypad, namely 0-9, * and #. An eighth tone was added so that some extra digits were available for use. These are commonly labelled ABCD. These eight tones were divided into two groups of four tones each, a low-frequency group and a high-frequency group.

This frequency group and a high-frequency group. This four-by-four array produced 16 different combinations.

Source: Click here

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Highway Speed Sensing & Automatic Breaking System

Project code:- E54 Project Cost:- INR:- Rs. 9000/- USD:- 225$
Every year ,we find more and more road accidents due to increased traffic on the roads, and if you see the statistics ,you will find that the causalities are more every year than that of 1970 Indo -Pak war. Experts says, increased motorist population, long working hours, stressful life, are the major cause. The factors are beyond one’s control , but if we could alert the driver on the highway,could save the many presicious lives.

Recieiver With Block diagram

Transmitter With Block diagram

I am not going to explain very complex solution for this,neither I claim to be an expert traffic controller . If we could fix up some sort of transmitter system on the highways which can detect the speed of the vehicle and convey to the driver that he is not in the permitted speed limit in the particular area or he is in a no horn area, or even further , if the automatic breaking system could be actuated on over speed.

As a prototype I have designed a transmitter and a receiver system . Receiver will be kept in the vehicles and transmitters would be installed on the road. I have not used any speed sensing device, instead four switches.which could be operated by traffic Cops, limit 80, limit40,limit20 and no horn area, are provided . when ever these switches are pressed, they will transmit the corresponding alert message to the driver .

Receiver section will have an 2X16 lcd, which will display the alert message ,and a relay circuit having three relays. One relay to sound alarm to driver. One relay for the auto breaking circuit . and one relay to disable horn in the no horn area.

Transmitter circuit: 
Transmitter consists of a microcontroller and 433mhz transmitter module .capacitor c1 and r2 gives the reset pulse to microcontroller reset pinX1 along with two 33 pf capacitor gives required the clock pulse to microcontroller.

Receiver circuit:
Receiver consists of a microcontroller ic2 and 2×16 lcd device for display purpose. Capacitor c3 and r2 gives the required reset pulse to the reset pin1 of the microcontroller. Alternatively a reset switch is also provided to mannaually reset the microcontroller. Capacitor c4,c5 along with the cryctal x1 gives the clock pulses to microcontroller ,this serially received data is displayed on the lcd.

Alarm switch connected to p1.0 pn 13 will Data transmitted from the transmitter is received by the 433mhz receiver and output from this receiver is connected to pin 2 of the microcontroller ic2.this serially received data is displayed on the lcd. Alarm switch connected to p1.0 pn 13 will switch off the alarm relay. Pin7,8&9 of the microcontroller controls the operaton of the relay.

These three relays are alarm relay,break relay and no horn relay. Transster Q4 and Q5 are drvers for relay K3, a break relay. Whenever speed limit is above 80 km/hour break relay will be operated and break relay will operate and break will be applied. When ever the vehicle is in no horn zone , no horn relay’normally close contact will open and driver will be prohibited to sound horn. Whenever vehicle receives any warning signal on his lcd a alarm will also sound which will be operated by the sound relay. Driver has a option to switch off the alarm after he see the alarm message on the lcd.

Limit 80,Limit 40, Limit 20 and Nohorn are the four keys conneted to mcrocontroller pin 67,8,9. one side of the keys is connected to ground, so whenever any key is pressed , that particular pin of the microcontroller will become low and microcontroller will will detect key press. If no key is pressed all these pins will stay high.

Corresponding messages are stored into microcontroller rom area . Microcontroller will read the corresponding message fron the ron area and shift out serially from the pin number 3 of the microcontroller.

data shifted out serially at the rate of 300bits per second. Output data fron the pin 3 of the icrocontroller is connected to the data in pin 2 of the 433mhx transmitter . the transmitter will transmit this data to air. Entire circuit is driven by 9v battery ic 1 is 5 v regulator which gives regulated 5v dc required for microcontroller and 433mhx trensmitter module. Ld1 gives the visual indication whenever any key is pressed.

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Power Saver

Project code:- E51 Project Cost:- INR:- Rs.9000/- USD:- 225$

We are facing an acute shortage of electrical power these days, every now and then there is a power cut in some part of our city . If we could save some power from our house, it could be utilized some where else, it could be a good contribution towards national development process.

You must have observed in your house that many times we forget to switch off lights and fans while leaving our rooms in hurry.These small things are neglected mostly by childrens and students, and has been observed by all of us in our day to day life.This gave me a thought to design a project through we could save electricity by switching OFF the fans when nobody is in the room or during day time the LIGHTS should remain OFF. This could be achieved automatically by using this project

Power Saver Block diagram

Operation: A pair of 38khz transmitter and a receive is fixed before the entry of the room across the entry and another pair is fixed inside the room just after the door across the enty points. In block diagram these are shown as TX1 RX1 AND TX2 RX2,Transmitters are operated by 2 AA size 1.5v batteries. Receivers are directly connected to the microcontroller board. Each receiver has three connection wires RED wire is for +5v power supply BLACK wire is for –ve and YELLOW wire is for out put of the receiver.These all wires should be connected to the respective connecter on to the microcontroller board otherwise you will damage the receiver part .Normally the output of the IR receiver remains HIGH when the beam is present you can check it with the multimeter between –ve and yellow wire terminal that is between black and yellow wire terminal. It should always be HIGH(+5v) when IR beam is present and there is no obstruction. Any one passing through the beam will obstruct the beam that will generate Low going pulse as the person passes by. You. Can check Low Voltage between black and yellow wire terminals.

Note : many time it is observerd that you donot chect the transmitter battery weather it is properly connected or not. many times I have found that battery was dead.and since student donot have the multimeter could not check the battery voltage. Please check that 3v dc is always available at the trnsmitter terminals ie red and black wire.If the voltage is still not available the possible fault could be rusty spring or bad contacts. or bad battery. Battery should be removed when it is not in use.

Microcontroller maintains a counter inside. . Please note that these counter will only work properly with single entry. If two peoples are coming together will be considred as single entry. Counters is automatically increased or decreased on entry or exit sensors and result is displayed on seven segment leds.Till the time ,counter value is non zero fan will remain ON inside the room Also the lights will come ON during night time or during low visibility time.

The light circuit is operated by a light sensing circuit operated by a LDR (light dependent resister.)

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Multipurpose Isolated Serial Input Output Module

Project code:- E50 Project Cost:- INR:- Rs. 7500/- USD:- 200$

Designed for control and sensing applications, this project provides 8 relay outputs and 4 optically isolated inputs. It can be used in various applications including load switching, external switch input sensing, contact closure and external voltage sensing.

Serial IO Block Diagram

It is controlled via a serial port using a set of simple text commands. Connection to the isolated inputs and relay outputs is via “pluggable type” screw terminal blocks The project presented here is based on world’s most powerful intel’s mcs-51 family of microcontroller atmel at89c51.In this project we are using AT 89C2051 microcontroller,since this controller has two ports are more than enough for our project.

Application area: the project can be used for various application wherever you require control using pc.

1 hotel power management

2.street light management

3.home automation

4.load shedding

5. High voltage grid control

6. Industrial automation

7.electro,hydrolic and pneumatic valve control

8. Robotic control and many more

All the above operation are possile from the ibm pc through com port.

User can control the devices using one of the following ways:-

1. Direct from pc using hyperterminal
2. Dialup network
3. Internet, using web applications
4. Through s.m.s.

User has to write his own codes for the pc , he is not require to write any code if he uses hyperterminal which is a part of all the window operating system .

This circuit can be connected to pc through com port provided. On pc normally two ports are available com1 & com2 this can be connected to any available com port, through a serial cable one normally used with modem ic max 232 is a level conver ter ic to convert ttl level data to +12v and –12v level for complete details on this ic, refer to manufacturer’s data sheet.

Using the serial port over a parallel port has several advantages:

1. Fewer wires are required (three instead of nine or more) 2. Serial cables can be a lot longer (up to 100ft),allowing “remote” control. 3. Serial ports can be used with any computer and operating system. The kit requires a 9-to-12V 1AMP AC power supply.

ASSEMBLY INSTRUCTIONS

Follow the component overlay on the PCB, starting with the resistors then diodes, IC sockets and crystal. Next fit the ceramic and monobloc capacitors, followed by the small electrolytic capacitors. Electrolytic capacitors are polarised, the positive lead is marked on the overlay, the negative is marked on the body of the capacitor.

Leave the large electrolytic until later.Fit the regulator next and use the 3mm screw and nut to attach the heatsink. All that remains is to fit the DC jack and D9 connector, followed by the relays and finally the large electrolytic capacitor.

Do not insert any ICs yet. Connect a power supply to the DC jack (centre positive) and measure the regulator output (5V). If OK disconnect the power and insert the ICs. Take care that the ICs are the correct way around and none of the leads are bent under the body of the IC.

Leds to the front panel. The PCB uses only four of the eight mounting posts on the bottom of the plastic case. Remove the four inner posts. They can be easily “snipped” off using wire cutters. Fit the front and rear panels to the PCB and hold in place.Slowly position the PCB into the base of the plastic case, making sure that the front and rear panels slide into the

Slots provided. Secure the PCB to the case using the selftapping screws. Fit and secure the lid.

CIRCUIT DESCRIPTION

This project started out as an extension of my previous project “HOTEL POWER MANAGEMENT”. . The circuit is very simple and straightforward. The brains of the kit is IC1, an 89C2051 microcontroller from Atmel. This was chosen because it has the required number of I/O pins and a built in serial port. It is pre-programmed to process all commands received via the serial port, control the relays and monitor the inputs. IC8 provides conversion between TTL and RS232 signals. To drive each of the relays. The opto-couplers, IC4-7, are used to provide electrical isolation between the inputs and the rest of the circuitry.At power-up, all relays are off (released) and the data LED is off. The data LED comes ON indicates proper functioning of microcontroller

OPERATION

Hyperterminal for Windows 98 . Start ® Programs ® Accessories ® hyperterminal

2. Double click on “Hypertrm.exe” to start the program. 3. In the “New Connection” dialog box, type in a name for this connection (eg. Myterm). Select an icon for this new connection then press OK. 4. The “Phone Number” dialog box will appear. Go to “Connect using” and select “Direct to Com 1” (orwhatever Com port the kit is connected to). Press OK

To continue. 5. The “Port Settings” dialog box will appear. Select the following then press OK.

· Bits per second : 9600

· Data bits : 8

· Parity : None

· Stop bits : 1

· Flow control : None

The program is now ready to go. When exiting you will be asked “Do you want to save session ?” Press “Yes”. A configuration file called “myterm.ht” is created with the” folder. Double click on this icon to start the program from now on. Way to test the kit is to use a terminal emulator program running on your computer. Run the program and set the communication parameters (asdescribed above). Connect the kit to the serial port on your PC using a straight through 9 pin cable. Switch on the power. The kit outputs an ‘#’ character as a prompt to indicate it is waiting to receive commands. Send a few commands to operate and release relays and check their status. Apply a voltage level to each of the inputs and read back its status. See also page 6 for this testing described in more detail.lator

COMMANDS

A set of simple text commands is used to control the relays, return their status or read the inputs. Each command consists of a string of ASCII characters followed by carriage return (Enter ¿). The ‘#’ character is output as a prompt to indicate the kit is waiting for a command. It should be on your screen. Each character received is echoed back. On completion of each command, good or bad, a carriage return/line feed combination is output followed by the ‘#’ prompt. If the command or parameter is invalid, the command is ignored and a ‘?’ is output before the next ‘#’ prompt. Note: · Commands are not processed until the carriage return character is received. · Commands can be in upper or lower case. · Relays are numbered 1 to 8. Relay number ‘0’ (zero) indicates ALL relays. · Inputs are numbered 1 to 4. Input number ‘0’ (zero) indicates ALL inputs.· Where a hex byte is used, each bit within the byte indicates its corresponding relay or input. Bit 0 indicates relay or input 1, bit 1 indicates relay or input 2, etc. Nx – Turn a relay ON (where x = relay number)

Eg. “N4” – turn on relay 4 “N0” – turn on ALL relays Fx – Turn a relay OFF (where x = relay number)

Eg. “F4” – turn off relay 4

“F0” – turn off ALL relays

Tx – TOGGLE a relay on/off (where x = relay number)

Changes the state of a relay (ON to OFF, OFF to ON)

Eg. “T6” – toggle relay 6

“T0” – toggle ALL relays

Rhh – Set ALL relays directly

“hh” is a hexadecimal byte. Each bit within the byte indicates whether the corresponding relay is operated or not. If the bit is ‘1’ then the relay is operated, if the bit is ‘0’ then the relay is released.

Eg. “R55” – relays 1,3,5,7 ON, all others OFF

“R0F” – relays 1-4 ON, all others OFF

Sx – relay STATUS (where x = relay number)

A ‘0’ (zero) is returned if the relay is released, ‘1’ if operated.

The command “S0” returns the status of ALL relays. In this case a hex byte is returned. Each bit within the byte indicates the status of the corresponding relay. Eg. “S3” – returns the status of relay 3 “S0” – returns the status of ALL relays

Ix – INPUT status (where x = input number) A ‘1’ is returned if the input is active or enabled, ‘0’ otherwise.

The command “I0” returns the status of ALL inputs. As with the ‘S’ command, a hex byte is returned. Bits 0-3 indicate the status of inputs 1-4. Bits 4-7 are unused and are set to ‘0’. Eg. “I1” – returns the status of input 1

“I0” – returns the status of ALL inputs A special command, ‘?’, will print the software revision date.

CONT………….

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Pic LCF Meter (Simple Monitoring of inductance, capacitance & frequency)

Project code:- E40 Project Cost:- INR:- Rs. 7500/- USD:- 200$

THIS simple PIC-based unit was designed to measure and display the values of inductors and capacitors.As a by-product of the technique used.it can also display the frequency of an external 0V/ +5V signal source The ranges are approximately:
Capacitance : 1pF to 6500uF
Inductance : 1uH to 10H
Frequency : 0.05Hz to 5MHz

The design is based upon the concept that osillators can be constructed from CMOS NAND gates or inverters.and that their oscillation frequency depends on the valuesof inductance. capacitance and resistance in their feedback paths. Using a suitable microconteroller. Such as one from the PIC 16F62x or PIC 16F87x

families. software can read the frequency of an oscillator and calculate the value of the ot- her components are known.In this design. A PIC16F628 is used and the results are output to an alphanumeric liquid crystal display (I.c.d.). One technique for using an inductor in a CMOS oscillator circuit is that shown in Fig.1.Here the oscillation frequency is determined by the formula:
F = _______1_______

2 x 7 x / ( L x C )

where:

F = frequency

C = C1 x C2

C1 x C2

L = inductance

7 = 22/7

Using this formula. If any two values are known. The third can be readily calculated For instance . if C and F are known. Than I can be calculated using the formula:

( 1_____)

L = ( 2 x 7 x F )

C

Similarly using the capacitance –resistance oscillator configuration ,.the output Frequency can be calculated for known values of R and C. several formulae exist for this calcUlation and the one used in this application is:

F = ____1____

7 x R x C

from which the value for C can be calculated if R and F are known:

C = 1___

7 x R x F

cont……………

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