1. 1 Designed by-Yogesh Kumar

2.  How to design a electronic system ?
 Block diagrams
 Electronic circuit
 HACS
 Mobile remote control
 DTMF & Cell phone
 Mobile network
 Signal Decoding
 MCU
 Interfacing MCU & 220VAC Mains supply
 Conclusion
2 Designed by-Yogesh Kumar

3.  Pick a problem from daily life.
 Check what you have & what you want ?
 Design flow of process.
 Draw block diagrams.
 Explore each process as you can.
 Now its time to design electronic circuit. Choose electronic
components as per requirement.
 Assemble & connect complete system circuit.
 Test it , Now your system is ready to work.
3 Designed by-Yogesh Kumar

4. Block diagrams
INPUT PROCESS PROCESS
SYSTEM FUNCTION
You Have
OUTPUT
You Want
4 Designed by-Yogesh Kumar

5. Electronic circuit
Clock Generator Decade Counter
5 Designed by-Yogesh Kumar

6. HACS
[Home Automation Control System]
Home Appliance Control System accessed by a remote device such
as mobile phone or a palm-top(PC) to allow a home owner to control,
monitor and coordinate home appliances.
The following picture gives an
overview of how the system is works.
HACS
is a system which provides
various services to remotely
operate on home appliances.
The HACS system receives
commands from remote devices that are
manipulated by user.
6 Designed by-Yogesh Kumar

7. Need of Automation
1. Saves time When: you are in a traffic jam
2. Save money (Long run) on the highway
3. Self Maintenance What: You set microwave
oven in a slow cooking mode
4. Security
5. Makes life easy
Oven
7 Designed by-Yogesh Kumar

8. Mobile Network & Remote Control
SMS Based DTMF-
DTMF Based High Compatibility with all cell MS
GSM Data logging phone models
Very cheap ,Easy to implement
BTS GSM / CDMA
NETWORK
BTS
8 MS
Designed by-Yogesh Kumar

9. DTMF Signals
 DTMF is a signalling system for identifying the keys or better say the
number dialled on a pushbutton or DTMF keypad.
 DTMF is a multi frequency tone dialling system used by the push
button keypads in telephone and mobile sets to convey the number or
key dialled by the caller.
 DTMF has enabled the long distance signalling of dialled numbers in
voice frequency range over telephone lines.
 DTMF (Dual tone multi frequency) as
the name suggests uses a combination of two
sine wave tones to represent a key.
These tones are called row and column
frequencies as they correspond to the layout of
a telephone keypad.
9 Designed by-Yogesh Kumar

10. DTMF signaling application
 DTMF tones are thus mainly used at the telephone switching
centres for detection of dialled/called number.
 IVR systems , Call centers ,Security systems.
 DTMF tones were also used by terrestrial stations for turning on
and shutting off remote transmitters.
10 Designed by-Yogesh Kumar

11. DTMF to BCD decoding
3.5 mm Jack
3.5 mm audio
connector
11 Designed by-Yogesh Kumar

12. 220VAC Mains Interfacing
12 Designed by-Yogesh Kumar

13. Mobile Remote Control System
DTMF Decoder chip
To/from Phone Jack
(Output/Input)
Data Access
Arrangement Chip
Voice Chip
Microcontroller
Outputs
SS Relay SS Relay SS Relay
Device No. 1 Device No. 2 Device No. 3
13 Designed by-Yogesh Kumar

14. MCU Electronic Circuit
14 Designed by-Yogesh Kumar

15. Project at a glance
15 Designed by-Yogesh Kumar

16. Want to ask ???
Any doubts or queries……
16 Designed by-Yogesh Kumar

17. 17 Designed by-Yogesh Kumar