International Journal of Engineering Trends and Technology (IJETT) – Vol4 issue5-May 2013
RIBBON CABLE (IDC) TEST JIG
A. Divya Sree#1, M. Anil Kumar*2, D. Spurthi#3
#
Student, Department of ECE, K L University, Guntur DT, AP, India
Vijayawada, Andhra Pradesh, India
Abstract: IDC cable, which mediates the data from one
device to another, is most commonly used in the
technical products. The problem that arises by using
this is – one cannot identify the pin at which the wire of
the ribbon gets short or open. This problem is solved by
us with a very low cost. Using the IC 7486, the logic to
test this ribbon was built and this reduces the manual
work of the user. The construction and working of the
circuit is simple as we made it only with logic using
basic components. Using this, the time taken to identify
the problem in the ribbon can be saved with no cost
because even the power consumed by the circuit is very
low.
Keywords: XOR gate, IDC ribbon cable, LED
indication, Test jig, IC7486.
I.
INTRODUCTION
An Insulation Displacement Cable (IDC),
also known as multi-wire planar cable is a cable with
many conducting wires travelling parallel to each
other on the same flat plane. It is used very frequently
in many electronic devices and machines for
continuous transmission of data.
Because the cable is compatible to all the
equipments and flexible to any atmosphere, the utility
of it became common. These ribbon cables are
mainly used in internal peripherals of devices,
computers and many other machinery. The wires of
the cable are closed and protect the data when passed
through it.
Each wire of the cable is independent of
other wires though they are attached together. It
consists of two female connectors at both the ends,
through which it can be connected to male connectors
of the device. These ribbons are of various types
depending upon the number of wires attached to each
other. These various types can be use according to
our requirement.
Fig. 1 Ribbon cable (IDC)
II.
PROBLEM
The only problem faced by the user with the
IDC ribbon is whenever the wires of the ribbon gets
short circuit to each other or gets open at any place
throughout the ribbon, one cannot identify the short
or open without opening the connectors. If the short
or open is to be traced, the user must open the
connectors on either side of the ribbon and manually
check the pins for problem. This consumes the
precious time of the user and is also a bit complicated
work.
III. SOLUTION
The risk of verifying the problem in the
ribbon manually can be reduced by using the test jig
prepared by us. Using this jig, user can test the ribbon
by just inserting into the male connector of the jig
and can know the type of problem (either short or
open) and also place of problem within no time.
The test jig is very simple to assemble and
the cost of making it is very cheap since it is made
with simple components. After experimenting with
high level components to make the testing of IDC
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International Journal of Engineering Trends and Technology (IJETT) – Vol4 issue5-May 2013
automatic, we learnt that this can be made too easy
even with basic components. The material used to
make the test circuit is a general purpose PCB, IC
7486 (XOR gate), resistors (value depends on the
voltage used, but generally need 200 ohms for 5v
source) 3 mm. LEDs and a male connector.
Fig. 4 Practical circuit for test jig
Fig. 2 IC74HC86 (XOR gate IC)
The pin diagram of IC 7486 with four XOR
gates appears as shown below
Fig. 5 Soldered side of the jig
Fig.3 Pin diagram of IC7486
This IC consists of 14 pins and four twoinput XOR gates. As shown above, seventh pin is
grounded and power supply will be given to
fourteenth pin. First and second pins of the IC are the
inputs of first XOR gate and third pin is the output of
it. Other three gates work in the same manner.
Generally, using 3 mm. LED with five volts
power supply requires 200 ohms resistance.
A.
Construction:
Here in our test jig, the odd pins of male
connector in the circuit are given logic ‘1’ and even
pins are given logic ‘0’( here ‘1’ indicates +5v and
‘0’ indicated GND). From the same connector, pin 1
is connected to first pin of IC 7486 and pin 2 is
connected to second pin of IC. Now, the third pin of
the IC is connected to LED via resistor. In the same
way, pin 3 of connector is connected to fourth pin of
the IC and pin 4 to fifth pin. Sixth pin of the IC is
connected to LED through a resistor. These
connections continuous according to the number of
wired ribbon used. The negative end of the LED will
be grounded. The number of ICs required depends on
the number of wires present in the ribbon.
B.
Working:
The basic logic behind this circuit can be
understood by knowing the truth table of XOR gate.
ISSN:2231-5381
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International Journal of Engineering Trends and Technology (IJETT) – Vol4 issue5-May 2013
V.
CONCLUSION
As the Insulation Displacement Cable is
used widely in the electronic world, our interest to
make the process of testing it easy made this jig and
it is being used by us in practice. In this competitive
world, every minute is precious and the perfect
industrialist goes on improves his business by not
only travelling with the standard process of
manufacturing products but also should focus on the
methods to make the same work easy with the
constant quality and less expenses. Keeping the same
idea in mind, the test jig for the IDC ribbon, which
saves the golden time of the user, is created by us,
which costs very less.
ACKNOWLEDGEMENT
This paper is made possible through the help
of my guides Ms. D. Spurthi and Mr. M. Anil Kumar.
I thank them for their technical support. I also thank
my parents for their continues encouragement.
Fig. 6 XOR gate representation and its truth table
By inserting the female connector of the
ribbon into the male connector of test jig, due to the
connections i.e. logic ‘1’ to odd pins and logic ‘0’ to
even pins, the input of XOR gate appear as ‘1’ and
‘0’ which makes the output of ‘1’ and makes the
LED glow. If there exists any short or open, the
inputs will be either ‘1’ and ‘1’ or ‘0’ and ‘0’, which
makes the output ‘0’ and the LED does not glow.
This indication of the LED not glowing resembles
problem in the pins of the ribbon wires connected to
that particular LED via IC. By this way, one can
easily find the faults in the ribbon within seconds and
solve the problem in flexible manner.
IV. ADVANTAGES
REFERENCES
[1]
Details of the ribbon can be studied
by
http://en.wikipedia.org/wiki/Insulationdisplacement_connector.
[2]
Various types of ribbons can
watched
in
http://www.google.co.in/search?q=idc+cable&hl
=en&tbm=isch&tbo=u&source=univ&sa=X&ei
=zd92UZTSGIiMrQf644DwBw&sqi=2&ved=0
CD4QsAQ&biw=1366&bih=616
[3]
Exclusive OR gate can be
understood
by
http://lyle.smu.edu/~lli/Lab1/lab_equip_notes.pd
f.
1. Saves the time of the user.
2. Manual work can be reduced.
3. Consumes low power.
4. Ribbon may not be wasted due to problem.
5. Flexible testing occurs.
ISSN:2231-5381
http://www.ijettjournal.org
1696