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MOBILE CONTROLLED HOME APPLIANCE WITHOUT MICRO CONTROLLER


INDEX
                                                    
SR.NO.
CHAPTERS
PAGE NO.
1
7
2
8
3
9
4
10
5
42
6
44
7
45
8
46
9
47
10
48
11
49
12
50
13
86


INTRODUCTION

Sometimes unfortunately we may forget switch off the appliances while going to the outside and we face the problems to switch off these devices when we are out of home. To solve these types of problems this article explains you how to design a simple circuit, which will other devices remotely and devices will off automatically after the specified time interval. Till Now we have seen so many circuits to control the devices or appliances from the remote Place but the main advantage of this circuit is simple because we are not using any Microcontroller in this circuit and it uses the components which are easily available in the Market we have already seen How DTMF Controlled Home Automation System Circuit Works using Microcontroller in the earlier post.  

  1.          Input 6 Voltage DC.
  2.       IOutput Load connect to Relay Switching 230V/50Hz
  3.       Power supply section input 230 voltage convert 6 voltage DC







 
















Mobile Phone Controlled Home Automation SystemDesign without Microcontroller:

     The main components in this circuit are MT8870 DTMF decoder and 555 timers. Here 555 Timer operates in Monostable mode. When you make a call to the mobile which is connected at the receiver end, MT8870 IC provides high pulse at 15th pin after receiving a valid signal. Now if you press 7 from the mobile the output decoder IC will trigger the 2nd pin of 555 timers. As a result the output at 3rd pin of 555 timers becomes high, so that transistor Q2 starts Conducting Because of this LED and Device on. The device on time can be varied by varying the Pot RV1 and capacitor C4. The device on time can be calculated using the formula

Time = 1.1 * RV1 * C4 sec.

In the above circuit device become on only when all the outputs of DTMF decoder (pin 11, pin12, pin13 and pin15) are high. To make all the outputs of DTMF decoder high we need to Press number 7 from the Dialled mobile

  • zMT8870 DTMF DECODER

















               The MT8870D/MT8870D-1 is a complete DTMF receiver integrating both the band split filter and digital decoder functions. The filter section uses switched capacitor techniques for high and low group filters; the decoder uses digital counting techniques to detect and decode all 16 DTMF tone pairs into a 4-bit code. External component count is minimized by on chip provision of a differential input amplifier, clock oscillator and latched three-state bus interface

Internal block diagram MT8870D



















Pin diagram
                                                
Pin Description


















Functional Description


The MT8870D/MT8870D-1 monolithic DTMF receiver offers small size, low power consumption and high performance. Its architecture consists of a band split filter section, which separates the high and low group tones, followed by a digital counting section which verifies the frequency and duration of the received tones before passing the corresponding code to the output bus.
Filter Section
          Separation of the low-group and high group tones is achieved by applying the DTMF signal to the inputs of two sixth-order switched capacitor band pass filters, the bandwidths of which correspond to the low and high group frequencies. The filter section also incorporates notches at 350 and 440 Hz for exceptional dial tone rejection (see Figure 3). Each filter output is followed by a single order switched capacitor filter section which smooths the signals prior to limiting. Limiting is performed by high-gain comparators which are provided with hysteresis to prevent detection of unwanted low-level signals. The outputs of the comparators provide full rail logic swings at the frequencies of the incoming DTMF signals.


Decoder Section
              Following the filter section is a decoder employing digital counting techniques to determine the frequencies of the incoming tones and to verify that they correspond to standard DTMF frequencies. A complex averaging algorithm protects against tone simulation by extraneous signals such as voice while providing tolerance to small frequency deviations and variations. This averaging algorithm has been developed to ensure an optimum combination of immunity to talk-off and tolerance to the presence of interfering frequencies (third tones) and noise. When the detector recognizes the presence of two valid  tones (this is referred to as the “signal condition” in some industry specifications) the “Early Steering” (ESt) output will go to an active state. Any subsequent loss of signal condition will cause ESt to assume an inactive state (see “Steering Circuit”).


Steering Circuit

               














         Before registration of a decoded tone pair, the receiver checks for a valid signal duration (referred to as character recognition condition). This check is performed by an external RC time constant driven by ESt. A logic high on ESt causes vc (see Figure 4) to rise as the capacitor discharges. Provided signal condition is maintained (ESt remains high) for the validation period (tGTP), vc reaches the threshold (VTSt) of the steering logic to register the tone pair, latching its corresponding 4-bit code (see Table 1) into the output latch. At this point the GT output is activated and drives vc to VDD. GT continues to drive high as long as ESt remains high. Finally, after a short delay to allow the output latch to settle, the delayed steering output flag (StD) goes high, signalling that a received tone pair has been registered. The contents of the output latch are made available on the 4-bit output bus by raising the three state control input (TOE) to a logic high. The steering circuit works in reverse to validate the interdigit pause between signals. Thus, as well as rejecting signals too short to be considered valid, the receiver will tolerate signal interruptions (dropout) too short to be considered a valid pause. This facility, together with the capability of selecting the steeringtime constants externally, allows the designer to tailor performance to meet a wide variety of system

requirements

              In many situations not requiring selection of tone duration and interdigital pause, the simple steering circuit shown in Figure 4 is applicable. Component values are chosen according to the formula:

                                    tREC=tDP+tGTP
                                    tID=tDA+tGTA

          The value of tDP is a device parameter and tREC is the minimum signal duration to be recognized by the receiver. A value for C of 0.1 mF is recommended for most applications, leaving R to be selected by the designer. Different steering arrangements may be used to select independently the guard times for tone present (tGTP) and tone absent (tGTA). This may be necessary to meet system specifications which place both accept and reject limits on both tone duration and inter digital pause. Guard time adjustment also allows the designer to tailor system parameters such as talk off and noise immunity. Increasing tREC improves talk-off performance since it reduces the probability that tones simulated by speech will maintain signal condition long enough to be registered. Alternatively, a relatively short tREC with a long tDO would be appropriate for extremely noisy environments where fast acquisition time and immunity to tone drop-outs are required. Design information for guard time adjustment is shown in Figure
























Functional Decode Table




Applications
• Receiver system for British Telecom (BT) or CEPT Spec (MT8870D-1)
• Paging systems
• Repeater systems/mobile radio
• Credit card systems
• Remote control
• Personal computers
• Telephone answering machine


Crystal KDS3.579545
















Description
This is a high quality 3.579545 MHz quartz crystal in HC49S casing. Every Microcontroller has inbuilt oscillator circuit, connecting this quartz crystal with controller forms the crystal oscillator circuit which provide the desired frequency to the processor.  This crystal is useful for DTMF decoder IC MT8870.
Product Features
·         Product Name : Crystal Oscillator; Frequency : 3.579545MHz;Pack
·         age : HC-49S
·         Frequency Tolerance : ±20ppm;Load Capacitance : 20PF;Frequency Stability : ± 20ppm
·         Mounting Type : DIP; No. of Pins : 2;Effective Series Resistance : 30 ohm
·         Mount Height(Each One) : 3mm;Mount Size(Each One) : 10.5 x 4.2mm(L * W. Max);Pin Length : 13mm
·         Material : Metal & Electronic Parts; Weight : 2g;Package Content : 3 x Crystal Oscillator



BC548 NPN TRANSISTOR











 QUICK REFERENCE DATA



LIMITING VALUES


In accordance with the Absolute Maximum Rating System (IEC 134)






























Note


  •      Transistor mounted on an FR4 printed-circuit board.





  •         THERMAL CHARACTERISTICS




Note



1.     Transistor mounted on an FR4 printed-circuit board.


CHARACTERISTICS





Tj = 25 C unless otherwise specified.




Notes

1. VBE sat decreases by about 1.7 mV/K with increasing temperature.
2. VBE decreases by about 2 mV/K with increasing temperature.



CHARACTERISTICS

DEFINITIONS




APPLICATIONS

  • General purpose switching and amplification.



LIFE SUPPORT APPLICATIONS

            These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such improper use or sale.

IC 555 TIMER























 Internal block diagram:
.




            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 Signe tics, the 555 is still in widespread use due to its ease of use, low price, and stability. It 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 Camenzind under contract to Signe tics, which was later acquired by Philips (now NXP).
        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).

        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  resistors used within,[3] 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.[4] 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. Those parts should generally be included, however, 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

                               
Pin Diagram
     








Pin description

Pin
Name
Purpose
1
GND
Ground reference voltage, low level (0 V)
2
TRIG
The OUT pin goes high and a timing interval starts when this input falls below 1/2 of CTRL voltage (hence TRIG is typically 1/3 VCC, CTRL being 2/3 VCC by default, if CTRL is left open).
3
OUT
This output is driven to approximately 1.7 V below +VCC or GND.
4
RESET
A timing interval may be reset by driving this input to GND, but the timing does not begin again until RESET rises above approximately 0.7 volts. Overrides TRIG which overrides THR.
5
CTRL
Provides "control" access to the internal voltage divider (by default, 2/3 VCC).
6
THR
The timing (OUT high) interval ends when the voltage at THR is greater than that at CTRL (2/3 VCC if CTRL is open).
7
DIS
Open collector output which may discharge a capacitor between intervals. In phase with output.
8
VCC
Positive supply voltage, which is usually between 3 and 15 V depending on the variation.

Pin 5 is also sometimes called the CO
NTROL VOLTAGE pin. By applying a voltage to the CONTROL VOLTAGE input one can alter the timing characteristics of the device. In most applications, the CONTROL VOLTAGE input is not used. It is usual to connect a 10 nF capacitor between pin 5 and 0 V to prevent interference. The CONTROL VOLTAGE input can be used to build an Astable multivibrator with a frequency modulated output

Mode

The 555 has three operating modes:
·         Monostable mode: In this mode, the 555 functions as a "one-shot" pulse generator.
·         Applications include timers, missing pulse detection, Bounce free switches, touch switches, frequency divider, capacitance measurement, pulse-width modulation (PWM) and so on.
·         Astable (free-running) mode: The 555 can operate as an oscillator. Uses include LED and lamp flashers, pulse generation, logic clocks, tone generation, security alarms,pulse position modulation and so on. The 555 can be used as a simple ADC, converting an analog value to a pulse length. E.g. selecting a thermistor as timing resistor allows the use of the 555 in a temperature sensor: the period of the output pulse is determined by the temperature. The use of a microprocessor based circuit can then convert the pulse period to temperature, linearize it and even provide calibration means.
·         Bistable mode or Schmitt trigger: The 555 can operate as a flip-flop, if the DIS pin is not connected and no capacitor is used. Uses include bounce-free latched switches.

Monostable













 RC circuit

Schematic of a 555 in monostable mode
                                                              
Waveform


















The relationships of the trigger signal, the voltage on C and the pulse width in monostable mode
In the monostable mode, the 555 timer acts as a "one-shot" pulse generator. The pulse begins when the 555 timer receives a signal at the trigger input that falls below a third of the voltage supply. The width of the output pulse is determined by the time constant of an RC network, which consists of a capacitor (C) and a resistor (R). The output pulse ends when the voltage on the capacitor equals 2/3 of the supply voltage. The output pulse width can be lengthened or shortened to the need of the specific application by adjusting the values of R and C.[5]
The output pulse width of time t, which is the time it takes to charge C to 2/3 of the supply voltage, is given by


where t is in seconds, R is in ohms (resistance) and C is in farads (capacitance).
While using the timer IC in monostable mode, the main disadvantage is that the time span between any two triggering pulses must be greater than the RC time constant
Specifications
These specifications apply to the NE555. Other 555 timers can have different specifications depending on the grade (military, medical, etc.).

Supply voltage (VCC)
4.5 to 15 V
Supply current (VCC = +5 V)
3 to 6 mA
Supply current (VCC = +15 V)
10 to 15 mA
Output current (maximum)
200 mA
Maximum Power dissipation
600 mW
Power consumption (minimum operating)
30 mW@5V, 225 mW@15V
Operating temperature
0 to 70 °

 RELAY



 









A relay is an electrically operated switch. Current flowing through the coil of the relay creates a magnetic field which attracts a lever and changes the switch contacts. The coil current can be on or off so relays have two switch positions and they are double throw (changeover) switches.
The relay’s switch connections are usually labelled COM (POLE), NC and NO:
COM/POLE= Common, NC and NO always connect to this; it is the moving part of the switch.
NC = Normally Closed, COM/POLE is connected to this when the relay coil is not magnetized.
NO = Normally Open, COM/POLE is connected to this when the relay coil is MAGNETIZED and vice versa.


A relay shown in the picture is an electromagnetic or mechanical relay.
Fig. Relay and its symbol
There are 5 Pins in a relay. Two pins A and B are two ends of a coil that are kept inside the relay. The coil is wound on a small rod that gets magnetized whenever current passes through it.
COM/POLE is always connected to NC(Normally connected) pin. As current is passed through the coil A, B, the pole gets connected to NO(Normally Open) pin of the relay

06 VDC- means that the voltage across the relay coil has to be 6V-DC.
50/60Hz- The relay can work under 50/60Hz AC.
5A,  240VAC- The maximum AC current and AC voltage specification that can be passed through NC, NO and pole pins/terminals of relay.

05VDC- It means that you need 5V to activate the relay. In other words, it means that the voltage across the relay coil has to be 5V-DC.
Tips
 - If you are using a 5-6V relay, use a 6V power supply.
- If you are using a 9V relay, use a 12V power supply

3.5mm audio jack
  A headphone jack is a socket found in audio devices that accepts pin-shaped headphone plugs. That works by transmitting an audio signals from an audio device to headphones by providing an electrical contact between the two. The most common type of headphone jack accepts 3.5mm plugs, also referred to as "mini jack plugs" and "1/8-inch plugs." The 3.5mm headphone jack or socket is standard on most handheld electronics with limited space, such as Mobile phones, digital audio players and vidcams. Netbooks and laptops also use this configuration, as do internal desktop audio cards. Advanced sound cards geared towards recording music often feature a separate patch bay with a full-sized headphone jack and inputs for musical instruments and microphones.  A headphone jack is typically located on the top or side of portable devices.







According to name convention, a 1/8-inch (3.5mm) headphone jack is an audio socket that accepts a 3.5mm male pin or audio plug. In electronics, a phone connector is a common family of connector typically used for analog signals, primarily audio. It is cylindrical in shape, typically with three contacts, although versions with two or four contacts are also common. Three-contact versions are known as TRS connectors, where T stands for "tip", R stands for "ring" and S stands for "sleeve". Similarly, two- and four-contact versions are called TS and TRRS connectors respectively. The 3.5 mm or miniature sizes were originally designed as two-conductor connectors for earpieces on transistor radios

CIRCUITS DIAGRAM














PRACTICAL CIRCUITS










Capacitor value(µf)
Resistors Value(MΩ)
Time
Mobile  Key
Input voltage
Input currant
63V/10µf
5MΩ
1Min.
6
5V
0.070mA
63V/10µf
4MΩ
49Sec.
3
5V
0.070mA
63V/10µf
3 MΩ
34Sec.
6,3
5V
0.070mA
63V/10µf
2 MΩ
23Sec.
6
5V
0.070mA
63V/10µf
1 MΩ
11Sec.
3,6
5V
0.070mA
35V/470µf
1 MΩ
8Min./10Sec.
3
5V
0.070mA
35V/470µf
2 MΩ
17Min./25Sec.
3
5V
0.072mA
35V/470µf
3 MΩ
24Min./35Sec.
3
5V
0.072mA
35V/470µf
4 MΩ
32Min./20Sec.
3
5V
0.072mA
450V/4.7 µf
1 MΩ
0.5Sec.
3
5V
0.073mA
450V/4.7 µf
2 MΩ
0.10Sec.
6
5V
0.073mA
450V/4.7 µf
3 MΩ
0.15Sec.
3
5V
0.073mA
450V/4.7 µf
4 MΩ
0.20Sec.
6
5V
0.073mA
63V/1 µf
4 MΩ
4Min.
3
5V
0.073mA
63V/1 µf
3 MΩ
3Min.
3
5V
0.073mA
63V/1 µf
2 MΩ
2Min.
3
5V
0.073mA
63V/1 µf
1 MΩ
1Min.
3
5V
0.073mA


·        We can avoid the wastage of power.
·        We can control the devices from long distances also.
·        Effective control of home appliances.
·        Home automation using mobile phone.
·        Increase power efficiency
·        Increase appliances lifetime.
·        Power wastage is reduced.
·        Quick response is achieved.
·        Construction is easy.
·        Easy to maintain and repair.
·        Comparatively the operation cost is less.  
·        Design is efficient and low cost.
·        Power consumption is low.
·        Controlling electrical devices wirelessly
·        Saves electricity (when we forget to switch off and go out).
·        We can control appliances from any place round the globe.
·        No coding is required.

                                  DISADVANTAGE
·        Security is not provided, anyone can control by making a call to the receiver mobile
·        Number of devices which we can connect to the circuit is limited.
·        This system is not capable of displaying the feedback status of
·        The devices being operated.
·        This system needs a cell phone to be placed in circuit.
·        Anyone who knows the phone number and code can control our electrical appliances
·        Number of electrical appliances that can be controlled by this circuit is limited

·        Used to control the home appliances
·        We can control the robot using this technology.
·        This circuit is used to control the water tank motor by setting the on time.
·        This system can be used in industrial applications.
·        This system can be employed in houses, where people often forget to switch off electrical appliances.
·        This system can be used to control AC’s to set the room temperature.
·        When we are outside.
·        We can extend this circuit to control many electrical devices with some modifications using 4 x16 decoder IC.


  •         Possibility of confirming the devices initial  condition
  •     (Status) using Calling system
  •  
  •     Though mobile in the control panel required to be  charged, therefore charging system should be automated
  •  
  •       Which meant a timer can be implemented so that mobile can be charged after a certain period and disconnected from the charger when not required.
  •  
  •       The system can be expanded to provide such control over the GPRS. In this way, the capabilities of the internet can be combined with the capabilities of our physical line free communication system. Furthermore, by adding a closed loop control facility, the system capabilities can be improved.
  • CONCLUSION

  •         Mobile phones have become an indispensable part of our life.  Our system uses a controller and a cellular phone for  its  operations. The systems can be used as a test bed  for  any  application that requires on-off switching based applications
  •       .Wireless controlled home appliances in the comforts of any environment will revolutionize our way of living. Controlling appliances remotely by a cell phone will one day become reality and one should give thanks to the capabilities of HACS.
  •           HACS might one day become a standard system in the new homes to come. 








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