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4v3 Zener & 680uH alternatives for Pickit 2 Clone

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sole_developer

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I'am trying to build a Pickit2 Clone available at: **broken link removed**

The problem is, I can't find a 4v3 Zener and a 680uH Inductor. Can I use a 100uH inductor instead of 680uH? Or should I build an Inductor (I don't think the design would accommodate it!). And can I substitute the 4v3 Zener with a 4v7 + resistor? Or should I use a LM385 (again, too lazy and I don't want to redesign the whole schematic here!)....

Thanks in advance guys!
 

for inductor you can use six or seven 100uH inductor in series. about zener diode if power dissipation is not important, you can
use a resistor in series with diode in form that .4V should drop on resistor.
 
Actually the original person has used the following diagram..I can't seem to figure out the resistor values if I use a 4v7 Zener.... I mean, is he caculating using (1/SQRT(1+RC)2)? How do I calculate the value of resistor required if using a 4v7 Zener...And which is a better for creating PCB Layouts from schematics, Proteus or Orcad? (which does a better job, placing components I mean, grouping all resistors, capacitors togethor, etc)....

Yes, I'am also considering using a 78LS33, but I'am gonna check if it is available first here!

Thanks in advance again!
 

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4V7 zener diode would need an additional voltage divider, 4V3 gives still to high output voltage (about 3.6 V), how about using a 3V9 Z-diode? You can tune the output voltage with a small resistor in series with the diode (10 ohms range)
 
I'am currently using Proteus Simulator to simulate this.....and it doesn't seem to be working! The vout voltage just drops to 0...I can simulate this type of thing in Proteus right??
 

As far as I'm aware of, Proteus has no problems with basic analog circuits. So it's most likely some kind of simulation circuit or configuration error.
 
FvM said:
4V7 zener diode would need an additional voltage divider, 4V3 gives still to high output voltage (about 3.6 V), how about using a 3V9 Z-diode? You can tune the output voltage with a small resistor in series with the diode (10 ohms range)
Click to expand...

How are you calculating the voltage, could you please let me know. And by the way, I found a 3v3 Zener.....How can I use the 3v3 Zener?
 

sole_developer said:
I'am trying to build a Pickit2 Clone available at: **broken link removed**

The problem is, I can't find a 4v3 Zener and a 680uH Inductor. Can I use a 100uH inductor instead of 680uH? Or should I build an Inductor (I don't think the design would accommodate it!). And can I substitute the 4v3 Zener with a 4v7 + resistor? Or should I use a LM385 (again, too lazy and I don't want to redesign the whole schematic here!)....

Thanks in advance guys!
Click to expand...

why not use 3v zenar in series with three in4148 diodes--3v+3(0.4v)=4.2v
 
shegzzyy said:
why not use 3v zenar in series with three in4148 diodes--3v+3(0.4v)=4.2v
Click to expand...

I need 3.3v at the output, but I can't figure out how the original guy is calculating the output voltage. Is he using the 1/SQRT(1+sq(wrc)) formula or what?? He has calculated based on the following diagram and using a 4v3 zener diode....I can't get a hold of 4v3, instead I have a 3v3 zener.......SO I just need to know how the output voltage is being calculated! Thanks again!
 

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No idea how you arrived at the formula. Output voltage will be zener voltage - transistor base-emitter voltage, e.g. 0.6V.
 
Re: 4v3 Zener & 680uH alternatives for Pickit 2 Clone

I think he arrived at vdd =4.3v-vbe-IeRe

- - - Updated - - -

I think he arrived at vdd =4.3v-vbe-IeRe

- - - Updated - - -

What of using a 3v and one in4148 in series?
3+0.4v=3.4v
 
Re: 4v3 Zener & 680uH alternatives for Pickit 2 Clone

shegzzyy said:
I think he arrived at vdd =4.3v-vbe-IeRe

- - - Updated - - -

I think he arrived at vdd =4.3v-vbe-IeRe

- - - Updated - - -

What of using a 3v and one in4148 in series?
3+0.4v=3.4v
Click to expand...

But according to the diagram, it doesn't make any sense.......Unless there is a voltage divide later on which he doesn't mention!

Actually I will just use a 4v7 in series with a resistor (to drop voltage by 0.4, I will try 10ohms)
 

Actually I will just use a 4v7 in series with a resistor (to drop voltage by 0.4, I will try 10ohms)
Click to expand...
That's what makes no sense in my view.

A 3.3V zener with 1N4148 in series would be a good guess, however.
 

Ok...sorry guys for the late reply (was busy with some things...)...I'am going to design the circuit from scratch (bummer!)...anyways, I will let you know...and I will also post my modified circuit! Anyways, I trited simulating the thing on Proteus, but didn't work....so I have installed Orcad and will let you know how it goes.....
 

PS: Anyone here work with Orcad?? I can't seem to find the footprint of a 48pin Zif Socket......! Or is there a better alternate designing software package which has these components already...so that I can just pick and choose..?? Like I saw someone make a PCB as shown in the image....was this done using Eagle..???? Please advise.
Thanks!
 

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