Presentation 1
Presentation 1
Presentation 1
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EXPLAINATION OF
BLOCKS
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OSCILLATOR:- It generates continuously
clock pulse.
GROUND COMPARATOR:- If ramp signal
is y and ground signal is 0,when ramp
signal is equal to ground signal ie.,y=0,
then ground comparator is ON and stop
pulse given to the gate ,then gate is
OFF.
SIMPLE RATE MULTIVIBRATOR:- It is
initialize the ramp generator and reset
to counter 0 after one pilse generates.
GATE:- It is a logic gate is ON when
start pulse comes and gate is OFF when
pulse comes is zero.
COUNTER:- It counts the clock pulse
passing through the gate.
READOUT:- It is seven segment display
which displays the gate pulse in
numeric form.
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WORKING
The input which should be measured is
given at input voltage. This input is fed to
ranging and attenuator circuit which will
amplify the signal if it is small or
attenuates the signal if it is large.
This is given to an input comparator
which will compare two signals and
generates the output. One input to
the input comparator is from the
input voltage and another input is
from the ramp. This input voltage and
ramp signal are compared and output
is given.
If the ramp signal is more than input
voltage there will be no output but if
the input voltage is greater than the
ramp signal then a is generated which
will open the gate. Now when the
gate gets opened, clock oscillator will
send clock pulses which are counted
by the counter and displayed on the
screen.
• The ground comparator will compare the
ramp signal and ground and output is
given. This output will stop the flow of
purchase from clock oscillator by closing
the gate. The sample rate multivibrator
is used to reset the
rampgenerator. Theoperating principle
of ramp type digital voltmeter is to
measure the time that a linear ramp
voltage takes to change from the level of
the input voltage to zero voltage (or vice
versa). This time interval is measured
with an electronic time interval counter
and the count is displayed as a number
of digits on electronic indicating tubes of
the output readout of the voltmeter
opens a gate .
The ramp voltage continues to decrease till it
reaches ground level (zero voltage). At this
instant, another comparator
called ground comparator generates a pulse
and closes the gate. During this time interval
pulses from a clock pulse generator pass
through the gate and are counted and
displayed.
The decimal number as indicated by the
readout is a measure of the value of
input voltage. The sample rate multivibrator
determines the rate at which the
measurement cycles are initiated. The sample
rate circuit provides an initiating pulse for the
ramp generator to start its next ramp voltage.
At the same time, it sends a pulse to the
counters which set all of them to 0.This
momentarily removes the digital display of the
readout.
TIMING DIAGRAM OF RAMP TYPE
DIGITAL VOLTMETER
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ADVANTAGES
1.ACCURACY-They provide high levels of accuracy in
voltage measurements due to their precise comparison
between the input voltage and ramp voltage.
1. Accuracy of output
greatly depends on
linearity of the
ramp(since only one se
ramp is used)
2. Input filter are needed
for filtering noise from
input signal.
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APPLICATION
It is used in laboratories
and research.
It is electronics testing and
manufacturing.
It is used in power
distribution systems.
It is used in automotive
industry
It is used in aerospace and
defense.
It is used in medical
equipments.
It is used in educational
institution
It is used in
telecommunication.
FUTURE WORK