Transcript pcb layout

Submitted to:Prof. Shivendra Singh
(Hod EC Dept.)
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Under guidance of
Prof. Nidhi Tiwari
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Introduction
Theory
Steps of making project
PCB Layout
ETCHING
Drilling
Component Mounting
Soldering
Circuit Diagram
Working
Advantages
 IVRS is a complete College Automation
System which takes in to account the three
important
dimensions
of
Educational
system namely students, teachers and
parents.
 This system becomes handy in order that
the parents get complete information about
their wards, in terms of attendance, class
tests marks and also the semester
examination.
 The main motto of this system to give the
information of student learning in college
such as accounts, marks, attendance .

Every student is assigned a unique pin number,
which is disclosed, only to the parents. The
parents can use their mobile or regular
telephone and using the pin numbers they can
get the complete information about their
wards.
 Interactive voice response or IVR is a
technology that allows a computer to
detect keypad inputs.
 Examples of typical IVR applications are:
telephone banking, televoting, call
center and credit card transactions.
 It also allows the option of choosing
automated services. Information can be
fed to the caller allowing choices such
as: wait in the queue, choose an
automated service, or request a
callback.
 PCB LAYOUT : Lay out of the desired
circuit is the most important in any
circuit board manufacturing process.
The following points are to be observed
while performing the layout of the PCB
Sufficient space should be maintained
between two components. High heat
dissipation
components
like
high
voltage resistors should be mounted at
a
sufficient
distance
from
the
semiconductors
and
electrolytic
capacitors. Components layout should
make proper combination with copper
side circuit layout.
 ETCHING:
The removal of excess
copper on the copper laminated PCB
apart from the printed circuit is known
as etching. Generally PCB is placed in
F3C13 solution
 DRILLING: Under this operation drilling
should be done as per circuit lay with
the suitable drill and high speed
machine. Drilling should always be done
from copper side to avoid possibility of
coming out of copper circuit
 COMPONENT
MOUNTING:
All
components are mounted at their
respective
position
as
per
the
components layout. Proper precautions
should be taken during mounting
process
 SOLDERING
TECHNIQUES:
A
soldered
connection
ensures
metal continuity. The soldering
process involves: Melting of the
flux which in turn removes the
oxide films on the metal to be
soldered. Melting the solder which
removes the impurities.
 When the incoming call comes, the first
pin of DTMF8870 senses the incoming call
and voltage of second pin of 8870 will
change from 2.5V to 1V.
 The comparator senses the change in
voltage of second pin and its output goes
up. This output is connected to the
microcontroller which senses the change
and gives an instruction to relay to switch
on the telephone hook switch.
 Simultaneously the microcontroller gives
an instruction to the PC to play the
welcome message.
 The caller is asked to press any key
and when pressed, this sensed by
DTMF 8870 and converted into
equivalent binary form.
 Binary form is sensed by MAX 232
through
micro
controller
and
converted into RS232 format which is
compatible to PC.
 As per the key pressed the software
decides what action should be taken
and the corresponding student
details will be delivered.
 As for example when the incoming calls
comes the ring is detected by the hardware
circuit and a welcome message “WELCOME
TO
TECHNOCRATS
INSTITUTE
OF
TECHNOLOGY AND SCIENCE” is played.
 Then it asks to enter the single digit roll no.
and after dialing the roll no. again, a
message “PRESS 1 FOR ATTENDANCE
DETAILS, PRESS 2 FOR MARKS DETAILS,
PRESS 3 FOR ACCOUNTS DETAILS AND
PRESS 9 FOR EXIT” is played.
 As per the key pressed corresponding data
is fetched from the database and the
message is played.
 The biggest advantage of IVR for small and large
organizations is to save time and money. IVR
systems can take care of most of the frequently
asked questions that an organization receives.
 IVR systems have the advantage of making
callers and customers feel like they're being
attended to.
 Another advantage is that IVR systems don't
sleep. They don't take lunch breaks. They don't
go on vacations. Thus information is given at
any time.
 This project is used for the college automation.
If database of every student of every college
under a university can be provided than it can be
used for the whole university automation.