hi welcome to another video tutorial from Robojax in this video we are going to do test and review
this pulse modulator to voltage converter made by IC station so their website is IC station
comm they send us this product for review and we are going to do honest review and see how this
works in many industrial application or maybe educational application you need to convert the
perfect modulation to the voltage so you want to find the relationship between the two to maybe
control a motor or whatever you want to do so this module will get a pulse width modulated
signal at an input and convert it to the voltage and will give you the output so the input can be
video 0 to 100 percent duty cycle and pulse width modulation and the output will be between 0 to 10
volts up to 10 volts so this is a module these two points are for the input which can accept between
12 to 30 volts and this is the signal pulse width modulated signal input and this is the voltage
output that signal will be converted we have a 12 volts voltage regulator here to keep the voltage
regulator so that's why it's safe to connect up to 30 volts and then we have potentiometer that
you can select the output voltage from here so the first is very safe because they have implemented
a photo coupler here and the input level of the coupler will be selected between with this jumper
so either between 5 to 12 volts which is this input 4 point 5 to 12 volts or 12 to 24 volts
so you just remove the jump the jumper and put it here so they use the PC eight one seven sharp
photo coupler with a four pin so this is the diagram so it has under than cathode so this
is the pulse modulation is coming here this will be used within the circuit so then the collector
and emitter of this transistor will be used in the circuits this is totally electronically
isolated when you select the input voltage when you connected here if it's if you set it here
we have a smaller resistors up to 12 volts this will come to this diode to the optic coupler diet
to the anode and signal will be coupled but if you are using it from towards to 24 volts this
2.7 kilo ohm resistors are or 1 will be on the path to reduce it and adjust it accordingly if
they use that lm35 8 low-power dual operational amplifier for this has a dual op-amp here so that
is that the op-amp so this is a dual 3 5 8 no power dual operational amplifier they've used it
so this is I see if station calm and this is the website the product page this has been explained
here so pulse width modulator and so this device can give us an output of 0 to 10 volts and the
input voltage that operates is 12 to 30 volts less than 200 milli ampere and pulse width modulation
frequency can be between 1 to 3 kilohertz and it has to setting with a jumper wire for the level
of the voltage can be either the pulse width modulation level can be either between 4 point
5 to 10 volts we have another jumper that you can set it between 12 to 24 volts and the conversion
is from 0 to 200 percent will be reflected to zero point 10 volts with 5 percent error
so let me explain the wiring here this is connected to the 12 volts I've connected
it to turtle this is connected to my function generator and this is connected this part is
connected to B to my multimeter here so this is my function generator that I've set this
the frequency is 2 kilohertz as you can see and that is in terms of micro second as 500
micro second so the duty cycle on the screen that you see if there's a 8% so if I sweep
down as you can see this will be like 8% or 7% and then at the middle this will be around 50%
and then if we go higher so that will be like hundred percent or so we can go from 0 to 99
point something so we will change this and see the output voltage now that now the module is
powered up and so now the module is powered up as you can see here we're at 28 percent duty
cycle and then you can see on the diagram it's almost let me put it around 25 so you can see
that this is one fourth of the screen so half of this is now we are at 25 percent and this
is a voltage that you are reading here so now I'm changing the duty cycle I reduce the duty
cycle from that value you can see the voltage is reflecting that percentage starts I'm jumping huge
so it's every time it's one percent so that's why you can see the voltage so I'm going faster
so now I'm at 30% we have to do volts it seems around 50% you are getting four point five
volts wait with a current setting you can adjust it based on what is you are getting
here so I have said that as you can see my function generator is set of five volts so
this affects pulse of five volts and this works just fine but if your value changes
this value is changing then you have to adjust it and fix it once you fix that you don't need
to touch it but if the value changes if you are moving this module from one device to
another device then you have to recalibrate and make sure that you are getting the right value
so let me go now I'm going to hire 60% 70% as you can see 92 Simon 99.9 I can go more
even so that's 99.9 have reached and that's we are getting seven point four volts once again
so this is pretty good this is pretty good very precise responsive and easy to use
to clarify something here this jumper is to select the input so at this position we are accepting the
input up to 10 volts if you're going from 2012 2012 to 24 volts you can see here at now at a
20% we're getting 2.3 volts when this jumper is here so if I switch this jumper from here
and then now you see disconnected there is no power so if I put it there now I'm getting one
point six seven five eight so you can adjust it again for different settings so once you move
it here this will reduce the input voltage so it can match with our characteristics of
the device as you can see my duty cycle is now 99.9% so this is full duty cycle the signal is
full and this should be the now we should so we should be getting maximum voltage so this
maximum voltage can be determined with this potentiometer 99.9 percent you want as a 7
point 4 volts or whatever so we can adjust it from this potentiometer so let's do that
and turning it to the right so I got the maximum
is now at eight point nine nine so that is the maximum voltage that I'm getting
so less than 5.7 volts you cannot do it
have connected now the voltmeter here so you can see whatever is the input power supply
voltage as 15.9 because it has a 12 volt regulator here you will see now the effect
of it so I'm reducing the voltage as you can see here this will not have any effect of this
because we have voltage regulators as soon as goes below the threshold of the input of this voltage
regulator then the output will be reflected so watch closely you see there is no difference at
14 volts 13 volts and now when we get closer to 12 you will see it you saw some changes
the value changed the input voltage saw 12 volts it changed again
at 11 volts and 10 volts so keep that in mind because it has belt and 12 volt regulator your
voltage must be 13 volts or higher so let's just check it again let's see I'm increasing
the voltage and see at what value this stops changing and that is the value of the minimum
value that you need minimum voltage when it is changing 13 is also changing the voltage
thirteen point seven so after thirteen point seven okay so as you can see thirteen point
four so thirteen point five sixteen point eight so 14 volt keep that in mind and then voltage
that you need is 14 volts for the input in order to get stable output voltage here now because I
have now stable output voltage now let's change this and see what we get not to forget now not
to forget that duty cycle is 99% and input signal is 5 volts so 99.9% that's full duty
cycle so let's change that adjust voltage so I'm turning it on rotating it clockwise so clockwise
increases the voltage but it seems that we are at the maximum because that's what we get nothing has
no we are getting more so the maximum it stopped at 10.12 volts so this is a
voltage that you are getting when input voltage is regulated so we get 12 verse
proper voltage here and then that is the 10 volts that you are getting the
maximum but if you want to change it I'm going back counterclockwise
so
so the monument that you are getting is six point five eight volts so you cannot
have lower voltages that you wanted like two or three volts or something like that that's
the minimum that I'm getting six point five eight volts now let's change the duty cycle
you
so here are the data for the different duty cycle I started from 1 up to hundred percent change the
value and also measure the voltage and entered all the values this is with the lowest possible output
with a potentiometer that I've selected using this potentiometer I set it to the minimum so
that lowest we got all this voltage when I plot it as you can see here it's very linear up to 80% of
up to 85% after this point but after that after just about 15% it's nonlinear that if for this
minimum value that we get then I measured for each turn increment at one percent and 10 percent and
20 40 60 and 80 and I measure the voltage to here or the voltage when I changed the potentiometers
to show the maximum voltage here then that's what I got so the initial voltage was zero point two
two and at the maximum when I said that I got zero point two five and we're at 10% when I was
getting 1 point 4 volts I got two point zero 6 and as you can see for 20 percent of same thing
the voltage increase from two point zero six to three point one and so forth so in this one I've
calculated the ratio between this and that so this is a formula so divide this by that and I
got the ratio one point one four and one point one seven after the initial value which was a
little odd because I should have started from two or three percent but anyway I started from
one so you see one point four seven one point five point four seven one point five it's very linear
the same exact replication of this will affect here so it will be the same type of linear plot
so keep that in mind the data is provided so you know better when you are using this module
thank you for watching this was the review test an introduction to IC station pal modulator to
voltage converter module please stamp up the video please share it and also subscribe appreciated
you