Mobile charger circuit design

 Mobile Charger circuit diagram

Objectives:

Ø  Designing  a mobile charger cheap in price.

Ø  Supported by  both AC and DC power supply.

Ø  Less power loss.

Ø  Small size and easy to Carry.

Ø  To present a charger that is good , efficient and better longevity to the society.

Apparatus:

ü  Transformer (9V AC,600mA)

ü  Diode(1N4007)-4 pieces

ü  Capacitor(100uF,50V)                      

ü  IC(LM7806CT)

ü  LED(3 pieces)                                                             

ü  Resistor:                                              

    R1=47

    R2=10R                      

ü   Clips(2  pieces)                                         

ü  Jack & holder

ü  Breadboard

ü  CCB board

Working  Procedure:

According to our circuit ,when we are using  AC power supply as input, the transformer steps down 220V   to 9V AC. Then the bridge rectifies it and converts it into pulsating DC which gets filtered by the capacit - -or. This becomes the input for the IC that stabilizes the DC at 6V. Then LED1 in the circuit, not letting excess current flow to the ground (working as a small resistance), provides an increase of more than 2V to the stabilized 6V.This increased DC voltage is used to recharge our battery. In this circuit LED3 is used just to indicate the flow of current, charging the battery. Giving protect to this LED3 we have used a 10 ohms resistance in series with it and to add protection for overflowing of  current a resistance of 47 ohms is used in parallel to the LED3 and the 10 ohms resistance.

 When Battery is in use the LED2 only is to show the existence of current flow or to indicate that the power source is now in DC mode. Here the use of capacitor,IC,LED1,LED3,47ohms and 10 ohms resistance is same as AC operation.

 Result:

Data across NOKIA 5130-Xpress Music

A.      When  only AC  activate

Without  Load

·         Voltage across DB=8.91V

·         DC Voltage Across C1=13.72V

·         IC input=13.03V

·         Output Current=0.34mA

·         Output Voltage=8V

·         Power loss=23.33%

            With Load

·         IC input=9.46V

·         Output Voltage=6.8V

·         Output Current=0.12mA

·         Power loss=27.58%

·         Charging time=4hr

B.      When  only Battery  activate

Without  Load

·         Battery voltage=12.45V

·         IC input=12.53V

·         Output Current=0.34mA

·         Output Voltage=8V

·         Power loss=19.17%

            With Load

·         IC input=12.32V

·         Output Voltage=4.49V

·         Output Current=0.15mA

·         Power loss=27.58%

·         Charging time=4.5hr

C.      When  Duel

  Without  Load

·         IC input=13.03V

·         Output Current=0.34mA

·         Output Voltage=8.03V

·         Power loss=44.1%

            With Load

·         IC input=13.61V

·         Output Voltage=6.8V

·         Output Current=0.13mA

·         Power loss=50%

·         Charging time=4.5hr

water pump control circuit design

INTRODUCTION:

Water pump controller  means something , which can control the water pump. That means it can automatically  control the pump/motor. When the water level is low, the controller will automatically switch on the motor  and when water is full in the water tank, it switch off the motor. It is the main objective of my water pump controller circuit.

OBJECTIVES:

—  To make a water pump controller circuit.

—  To design a simple circuit than the market products.

—  To minimize the cost.

—  To make the circuit small & light weight.

—   Increasing efficiency.

WHY WATER PUMP CONTROLLER:

For the supply of water it is very common method to use tank. Generally a person has to manually switch on the water pump when the tank is running low of water. Also when the tank is filled a person has to switch off the water pump manually. This process is inefficient because the person has no idea about the current water level in the tank. Therefore it cannot be known when the water is going to run out and when the tank is filled up, until the actual thing occurs. This may cause unexpected cut off of water supply. Also when the water is being pumped up the person has to wait until water overflows and then switch off the water pump. To improve this to certain extent sensors can be placed in the tank to measure the water level. Then the person can monitor the water level in the tank and can take necessary actions. In this system sensors are used to measure the water level in the tank and the water pumped is automatically switched on and switched off as required. This system minimizes human intervention and eliminates the inefficiencies described above.

Apparatus:

1. DC power supply(6V)

2. AC power supply(220V)

3. Flip flop IC(74279),1 piece

4. NPN Transistor(BC547), 4 pieces

5. Relay(6 volt), 1piece

6. Resistor(10k,10k 4.7k.4.7k), 4 pieces

7 diod(1N4007), 1 piece

8.capacitor(0.1uF)), 1 piece

9. LED, 2 pieces

10. Connecting wire, as required

THEORY:

The working principle series of automatic water pump controller above is, At the time the water level is below both sensors, then the output of flip flop will be one and active relay through the transistor and turn on the water pump. When the water touch the higher level sensor then the relay becomes off. Thus the motor becomes off. When the water does not touch all the sensors the relay becomes on and the water pump will turn on and when all the sensors touches water the relay turns off. Automatic water pump controller can be used to fill or drain the water according to which mode is selected via the relay.

TRUTH TABLE:

INPUT	INPUT	OUTPUT
Set	Reset	Q
1	0	0
1	1	0
0	1	1
1	1	1
0	0	1

SWITCHING ACTION OF TRANSISTOR:

Here I use an n-p-n transistor for switching. The base of the circuit connected with the output of IC. I get output from collector. When the power on then the base-emitter junction is forward bias and when power off then base-emitter junction is reverse bias.

BIASING CIRCUIT:  

 The proper flow of zero signal collector current and the maintenance of proper collector-emitter voltage during the passage of signal is called transistor biasing. Here for transistor performed well we use biasing circuit.

CIRCUIT OPERATION:

In the circuit, we have used 3 transistors (u1, u3, u4) as sensor. The ground level of the tank is connected with the dc voltage source. When the water level doesn’t touch any of the sensors then the transistor u1 remains off. Then the dc voltage comes through the resistor R3 and turns on the transistor u4. Thus the ground becomes connected with the set of RS flip-flop. So the input of set is negative or 0 and there is no voltage at reset. As a result we get voltage or 1 at the output of flip-flop. This voltage goes through the resistor R4 and turns on the transistor u2. So, the relay becomes ON and the ac power supply becomes connected to the motor and turns it on. By increasing when the water level touches the upper sensor then it turns on the transistor u3 and the ground becomes connected with reset of the flip-flop. So input at reset is negative or 0. As a result the output is zero. So, the voltage at the base of u2 is zero and the transistor becomes of. As a result the relay turns off and ac power supply is disconnected with the motor. Thus when the water level again goes below the lower level sensor then the motor will automatically switch on. The capacitor is used to reduce the noise.

           

LED charger circuit design

Introduction :

                                            A light-emitting-diode charger is a solid-state lamp that uses light-emitting   diodes(LEDs) as the source of light. Since the light output of individual light-emitting diodes is small compared to incandescent and compact fluorescent lamps, multiple diodes are often used together. In recent years, as diode technology has improved, high power light-emitting diodes with higher lumen output are making it possible to replace other charger  lights with LED charger light. As a prospect   our project is on “LED CHARGER LIGHT”.

AIMS:

                 1. To make a new LED charger capable of   some better facilities  than market products.

                 2. To provide more life time of LED charger than market products.

                 3. To give auto controlling system that always not present in market products.

                 4. To convey why   our charger is better than market chargers .

          5.    To make a cost comparison between our charger and market chargers.

   6. To transmit some future ideas about this charger , etc.                

EQUIPMENTS   WE USED :

                                          1.  POWER SUPPLY -220V, 50HZ.

                                                   2.  CAPACITOR-250V, 1UF-1 PIECE

                                  3.  DIODES (1N4007)-5 PIECES.

                                  4.  TRANSISTOR (BC557AP)-1 PIECE

                                  5.  RESISTORS-(15 KΩ, 4.7KΩ,1Ω)

                                    6.  SWITCHES

                                    7.  LED-12 PIECES.

                                  8.  CONNECTING WIRES.                         

 1. BRIDGE RECTIFIER:

                             For the led charger we need d.c supply. For that  reason we use bridge rectifier circuit. It contains   four diodes connected to form bridge. We use 1N4007 series diodes. For the positive half cycle of a.c signal diodes d1 and d2  are forward biased and d3 ,d4 are reverse biased . During the negative half cycle of a.c signal diodes d1,d2 are reverse biased and diodes d3,d4 are forward biased. As a result we get d.c output  all the time . Which is needed  for our led charger circuit.

2. FILTER CIRCUIT:

                                       Here we get d.c. output from bridge rectifier circuit but this d.c is not perfect d.c because it has ripple. For removing ripple we use a filter circuit which mainly removes ripple. For this we use a capacitor and a resistor, capacitor connected parallel. Because    capacitor   blocks  d.c and passes a.c. So when capacitor passes the a.c signal and opposes the d.c   then we get   perfect d.c.the range of the capacitor is 10 micro farade.

3. BIASING CIRCUIT:

                   The proper flow of zero signal collector current and the maintenance of proper collector-emitter voltage during the passage of signal is called transistor biasing. Here for transistor performed well we use biasing circuit.

4. SWITCHING ACTION OF TRANSISTOR:

                                           Here we use a p-n-p   transistor for switching. The base of the circuit connected with the rectified output. we give input in the emitter and get output from collector. When the power off then the base-emitter junction is forward bias and when power on then base-emitter junction is reverse bias and as a result LED is off.

5. LED connection :

                              In the circuit leds are connected in parallel connection. If we connect the leds series then if one led is damaged then the panel will be unable to illuminate because current flow from one led to another led. For removing this problem we connect the leds in parallel connection. In our circuit we used two panels of leds .

PARAMETER READINGS:

•      Input voltage- 220v 50Hz

•      Voltage drop across LED panel-  2.15v

•      Current  across LEDS- 22.5 mA

D.C Ballast

Circuit diagram

INTRODUCTION:

In the world of electronics, there is a great importance of dc ballast .We need this kind of device for getting our requisite ac current from dc input .The availability of ac power supply is not as good as dc supply .The places where we don’t get ac current for our practical use, we can get ac supply by using dc ballast. In this case we use dc current as input .Again, in many electronic devices such as gas-discharge tube, we need high voltage to get light. So DC ballast is very useful .

OBJECTIVES:

The main objective of dc ballast is to create such a high voltage enough to light a gas discharge tube .Gas discharge lamps generate light by sending an electrical discharge through ionized gas .In the operation of gas discharge tube, the gas is ionized and free electrons are accelerated  by the electrical field in the tube . For this we need very high voltage as input. The required high voltage is provided by dc ballast using low voltage dc supply .A dc ballast provides the features of low cost and higher reliability .Here we attempted to convert low dc voltage to high ac voltage to light a gas discharge bulb using dc ballast.

 

 

 

APPARATUS REQUIRED:

1. E core

2.Transistor CTC2233(2 pieces)

3. Inductor

4. Ceramic capacitor (2 pieces - 1 micro farad, 0.01 micro farad)

5. Resistor (1 piece-300ohm)

  OPERATION:

         When we apply dc voltage as input, then we get the current divided in two branch; minimum current pass through the resistance R1 and maximum current pass through the inductor L5, as we know that dc is short there .Then the maximum current will flow through the coil L1 and L2 within a short difference of time .It is an astable multivibrator .So, it has no stable state .It switches back and forward  from one state to other .As, the capacitor C1 started to charge and we get a induced voltage in L3 because of L1 .

                                                   When the current from L1 passes through the transistor U2, it becomes on and then the U1 is in off situation .In other side, the current also flow in L2 .As a result C1 started to charge from opposite side become discharged from the first side .Here, we also get a negative  induced voltage in L3 .As a result U1 becomes on .It is a continious process .Then, this found ac voltage will be steped up in L4 coil .A capacitor C2 is connected, so that ac current can pass easily in that output circuit. Thus we get our required output ac voltage.

EXPERIMENTAL RESULTS:

Input  voltage, Vi=12V;

Output voltage, Vo=1587.4V;

Input  current, Ii=1.85A;

Output current, Io=12.60mA;

Input power, Pi=22.2W;

Output power, Po=20.1 W;

Vc= 11V;

Ve= 0.075V;

Vb = 3.8V;

Vbe = 3.8V;

Vce = 11V;

Vcb =  15V;

 

 

Calling Bell circuit design

Project-01. Calling Bell circuit diagram.

Description

The project provides the schematic and the parts list needed to construct a musical door bell. The door bell is operated at 1.5v-3.0v as well as with an musical IC (UM66) to make the circuit. As a modified circuit it is successfully operated in ac supply as well as in dc supply when ac supply will be turned off as we required.    

The circuit has been built using the basic characteristics of transistors. A musical IC UM66 is used to generate musical tone which is further amplified using a transistor. The charging time of the capacitor can be controlled by the variable resistor of 100KΩ. For AC power supply, two 470KΩ resistors is used along with a bipolar capacitor of 250V in parallel. Then a bridge network is connected to convert AC to DC.  Zener diode in parallel makes the voltage constant. This constant voltage ensures the power source for the circuit. At the same time it is connected with the base of the PNP transistor. When AC supply is on the E-B is reverse biased, so no current will flow through the Base to Collector. In this way the battery source is switched off. But if the AC power is off the transistor becomes forward biased. So the current will conduct through base to collector. In this way, the power source for the circuit is automatically switched to the available power source.


Circuit Description:
There we have used a 1.0µF capacitor and two 470k resistors by replacing transformer. Then a bridge rectifier is used to supply the input voltage to the main door bell circuit. The output voltage of our supply is 4v which is required to operate the door bell. At the modified section we have used a p-n-p transistor (BC557AP),a resistor(500Ω) and two diodes(1N4001GP) which will operate the circuit in dc supply in the absence of ac supply as we predicted. 

Apparatus:

—  IC                         (UM66)                                      1pc

—  Speaker                (8 Ω  0.5W)                                1pc

—  Diode                    1N4007)                                     5pcs

                              1N4732 (Vz = 4.70V)                  1pc

—  Capacitor              1µF (bipolar) 250V                     1pc

                                   220µF                                         2pcs

—  Resistors               470KΩ                                       2pcs

                                    100 Ω                                        1pc

                                    4.7K Ω                                      1pc

                                    500 Ω                                        1pc

—  Transistor              BC 557                                      1pc

                                    BC548                                       2pcs