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If anybody need help in EAGLE, ask me in this POST !

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Yep thanks =)
and for the power pins, 4 to GND and 8 to +5V ? Or to the output of the LM317, so 3V ?
In the datasheet it is written V+ = 5.0 Vdc ... so 5V always ?

so here's the final version of the scheme View attachment scheme.zip if someone could tell me if I should modify/remove/add some things etc etc ... remarks ..

the fm module is to be powered under 3v and the rest 5V ...
 
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You can run the LM358 on up to 32V, although I would suggest a little less!

The LM358 power supplies are drawn so you can position them over one of the opamps.

You have a lot of gain there. I don't know if there is a DC offset on the FM Module output but I think you will have problems. I would suggest you look at the AC amplifier at the top of page 16 of the datasheet instead.

A title other than "untitled" would be a good idea!

Keith.
 

The LM358 power supplies are drawn so you can position them over one of the opamps.
Click to expand...
what do you mean ? Did I make a mistake ? I've "invoked" them and I connected the pin number 4 to GND and 8 to +Vcc 5V ...

You have a lot of gain there. I don't know if there is a DC offset on the FM Module output but I think you will have problems. I would suggest you look at the AC amplifier at the top of page 16 of the datasheet instead.
Click to expand...

Here is the datasheet of the module https://www.sparkfun.com/products/8972 ... so it is written to connect an opAmp and a jack ... so it is to amplify the output voltage of pins LOUT and ROUT ... right ? so why AC amplifier as I don't use AC power ? =)

and what do you mean by a DC offset .... should I choose resistors with less values ? ..

Thanks
 

The power connections to the LM358 are connected correctly, but it would look tidier if they were on top of one of the opamps so the power pins appear to come from the opamp triangle. It isn't important though.

I suggest you use the AC coupled amplifier as I recommended above but with lower gain than you currently have. The FM module has a decent output so a gain of 10 should be enough.

The AC coupling is nothing to do with the power supply. The FM audio output is AC so it makes sense to AC couple it.

Keith
 

Hmm ... how do you know the output of pins ROUT and LOUT is AC power ? and not DC ... in the features, it's written 100mV, in the doc 115 mVr

but won't it be harder to make the circuit with the AC amplifier scheme ? A lot of components in addition :/
Why can't I use the "non inverting DC gain" ? (with a gain of 11 if I choose R2 and R1 to make R2/R1 = 10)
ps : just trying to understand :)
 

I KNOW that audio is AC. The FM module doesn't say if the output is DC coupled but it doesn't really matter. If it is AC coupled then DC coupling a voltage follower won't work because there is no DC path to supply the opamp input bias current, if it is DC coupled then the opamp will hit the rails due to the high DC gain.

So, use the AC coupled circuit. Don't call it AC power - it is a signal not power.

Also, add capacitors from the opamp output to the connector. I don't know what you are planning to drive but it probably won't want a DC voltage on it.

Keith
 

We told me that 100mv output voltage is not enough for a sound .... and that I should add an amp on ROUT and LOUT to amplify the signal if I was planning to connect headphone
That's why I am putting an amp ;)

Ok so I'll use the "AC coupled inverting amplifier" scheme (not the non-inverting one) and not the DC one ... even if I choose R2 = 100 K ? So the gain would be 11 ...

For Cin, value ? 22pF ? or too low ? 100µF ? and for Co

Thanks again =)

edit : what about using TDAs amp ? They are designed for audio amp ;) Just need to connect the pins and that's it ! Good ? =D
the tda2006v .. http://www.datasheetcatalog.org/datasheet/stmicroelectronics/1452.pdf it's on eagle also .. but power supply mini 6V =( And I just have 5V and 3V ... (and the 9V of the main supply but I don't think it'd be good ?)
if you have another model ;)
 
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If you want to drive headphones, for example, a dedicated audio amp would be better. Have a look at National Semiconductor's web site. Or maybe start a new thread on one of the other forums on here - it isn't an Eagle question anymore and you will get some advice from people who have used the audio chips.

Keith
 

I need help with manually creating a drill file.

I am a long time "professional" CAD user (Cadence and Mentor), and am used to creating my manufacturing files manually (i.e., unscripted).

I have inherited a design done in Eagle, and need to generate a drill file. I have successfully created all 4 solder layers, both solder mask layers, and silk screen layer gerbers, but am having trouble with the drill file.

I am using Eagle 5.10.0 (for Windows). I believe that with this version, I do not need to mess with the EXCELLON_RACK generation or the .upd script. To create my drill file, I selected a device of EXCELLON, named my output file, and then selected layers: Drills and Holes. I then selected "Process Job."

When I look at the resultant file, it looks like the processor used different units. For example, the board is 3" by 4". Therefore, I would expect all hole locations to have X values less than 3000 and Y values less than 4000. However, if I look at the file in a text editor, I see values greater than 20,000 and 11,000. Also, if I try to look at the drill file in graphic editor, it looks wrong.

In viewmate, it is completely wrong -- the holes seem almost randomly placed (at very large dimensions, i.e., x = 20", y = 19". If I open the drill file in a different viewer: viewplot, the holes look like they should, relative to each other, but on a 3x or 4x scale relative to the actual board dimensions.

Am I missing something simple here, or do I have a more serious problem?

Edit: I think it is the number format. Eagle defaults to 2:4, where as Allegro (and viewmate and viewplot) default to 2:3. If when I load drill file into viewplot and specify a number format of 2:4, the holes end up exactly where they should be...
 
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I think the numbers are in 1/10000 inch = check the .dri file. If so, you probably have 1 digit before the decimal point and 4 after. So your 20,000 will be 2 inches etc. You could post the gerbers & drill files here and I can load them.

Keith.
 

I just had to edit my edit -- the viewers default to 2:3 (i.e., 2 digits before, 3 digits after the decimal place) -- this agrees w/ what Keith is saying. Thanks for the sanity check.
 

If any component have VCC and GND pin with pwr marking what does it mean?
does it mean we dont have to connect VCC and GND to these pins these pins are not apiarring in the schematic
but erc check showing that VCC and GND not connected.
 

I only use the PWR pin designation for DRC. PWR pins will be checked for shorts to other PWR pins with a different name and also to make sure they are connected to PWR. It will give false warnings such as if you connect a PWR pin names VCC to a power pin names +3V3 but that is not necessarily an error.

Eagle will connect the PWR nets with the same name even if they aren't shown on the schematic. You can easily check this - add a few parts without a power pin shown & then switch to the board. However, I think it is better to explicitly connect them so there is no ambiguity about what connects where.

Usually parts actually do have explicit power pins but they must be added by using INVOKE. Personally I create all my new parts with explicit power pins as part of the device so you always get them.

Keith.
 

I cannot be certain of the library name (I think it changed between versions) but I think it is 'quartz' or 'crystal'

Keith
 

Re: eagle autoplace

Hi.

I have had a go at making my own Lbr files for Eagle, but to no avail.

There are some parts that I require these files for, can you please help:?:

Pt1 LM2678-7pin Adjustable TO-263 SMD case. May be the LM22678 also.

Pt2 LM1084 5Amp low dropout Reg TO-263 SMD case.

Pt3 ST5PF20V Power Mosfet SO-8 SMD case.

Thanks in anticipation.8)
 

You really need to learn how to make your own library parts. It is not that difficult and there are some good tutorials on the internet.

You already have standard packages so the job is half done. Copy the package from another library. There is a library called ref-packages I think.

It is always worth checking the Cadsoft web site as people upload libraries there.

Keith
 

Hi Keith

OK, I will carry on and learn, it was the LM2678 that I needed badly and I have been pulling my hair out with.


Thanks.
 

Hi Keith

Thank you for that info tip. I will investigate later.

Regards

alan
 

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