Eagle Schematic Reference Design

LucidGuppy

Hello,

I've started up a reference design in eagle. Its using the full up version of the program so I don't know if the lite version can open it. I created the eeprom part and the prop part so that eagle users can create propeller schematics.

If anyone is looking for it to be posted I will - but right now I'll post pictures.

Kind Regards,
LucidGuppy

T Chap

I'll take them both! Thanks

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something smells like it's on fire

Scott E

I would like a copy as well. Thanks

Seeker

LucidGuppy said...
Hello,

I've started up a reference design in eagle. Its using the full up version of the program so I don't know if the lite version can open it. I created the eeprom part and the prop part so that eagle users can create propeller schematics.

If anyone is looking for it to be posted I will - but right now I'll post pictures.

Kind Regards,
LucidGuppy

Please post.· It'll save me tons of work.

Thanks from all of us!

APStech-Attila

Dear Lucidguppy,

··· I have several "3 transistor programmer" PCBs, with the same schematic, you posted,·but they do not work very well. (The reset signal needs to be inverted for better performace) and if you use hyper terminal, it can ruin your voltage supply for RS232 level generating circuit.

·· A MAX3232 version works really nice (see PropStick sch.)



Regards,

· Attila

LucidGuppy

Sorry everyone,· I've been a little busy the past two days I wont get back to my work computer till tomorrow. I'll post the board after I make some changes.

I'll put in the max232, and invert the reset line.

Sorry for the wait.
-Guppy

LoopyByteloose

Eagle LITE will read any and all Eagle Files.
It just won't create files beyond the double sided and half-Euro card limits.

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"If you want more fiber, eat the package.· Not enough?· Eat the manual."········

···················· Tropical regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

LucidGuppy

Here are the files so far...I'm going to work on them when I can.

Please poke holes in it - as it would help my designs.

Seeker

Thank you SO much. I'll look at them tonight and let you know what I find.

LucidGuppy

What was the problem with the transistor inverting the signal? What performance degradation did you get?

Attila said...

Dear Lucidguppy,

I have several "3 transistor programmer" PCBs, with the same schematic, you posted, but they do not work very well. (The reset signal needs to be inverted for better performace) and if you use hyper terminal, it can ruin your voltage supply for RS232 level generating circuit.

A MAX3232 version works really nice (see PropStick sch.)



Regards,

Attila

Seeker

So far it looks great. But what is IC1? My guess, a RAM/EEPROM IC.

I can tell you put a lot of work into this. It is just what I was hoping for. Once you feel it is ready, you should submit this to the Eagle library.

LucidGuppy

For my schematic I was going to us 317 regulators with 1 % resistors·for a 3.3 and 5.0 rail.· I would have used 78xx series but they don't go down to 3.3, and I can use the same part for both rails.

Any objections?

Seeker

LucidGuppy said...

For my schematic I was going to us 317 regulators with 1 % resistors·for a 3.3 and 5.0 rail.· I would have used 78xx series but they don't go down to 3.3, and I can use the same part for both rails.

Any objections?

No objections....



But there is the 78M33C 3.3 volt regulator.· It might save you some board space and soldering time.

RinksCustoms

You can order a free catalog from http://www.mouser.com where you can find 3.3V / 5.0V regulators up to i think 5A in a 220AB pkg.

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Definetly a E³ (Electronics Engineer Extrodinare!)
"I laugh in the face of imposible,... not because i know it all, ... but because I don't know well enough!"

Phil Pilgrim (PhiPi)

Some things to check with voltage regulators:

1. If you drive the 3.3V regulator from 5V, make sure the dropout voltage on the 3.3V unit is at most 1.7V.
2. Be sure to use the right caps on both input and output. Some regulators — especially the low-dropout types — are very fussy about minimum capacitance and both minimum and maximum ESR (equivalent series resistance).
3. Some regulators (like the LM2940) are reverse battery protected. This is a huge plus in an experimental environment!

-Phil

Seeker

Phil Pilgrim (PhiPi) said...
Some things to check with voltage regulators:

1. If you drive the 3.3V regulator from 5V, make sure the dropout voltage on the 3.3V unit is at most 1.7V.
2. Be sure to use the right caps on both input and output. Some regulators — especially the low-dropout types — are very fussy about minimum capacitance and both minimum and maximum ESR (equivalent series resistance).
3. Some regulators (like the LM2940) are reverse battery protected. This is a huge plus in an experimental environment!

-Phil

Good advice.· Number 1 has bit me on the butt more than once.· That's why I power all voltage regulators from the main (for me, 8.6v - 11.1v) instead of cascading them.· Less to worry about.