complete project

[satdaveuk]

Thanks

Hi Tinker
Hope your move goes smoothly and you recover the data from your hard drive ok.
Thanks for the design spark application, have downloaded it and when time permits will have a play.
Didn't know this program existed until you mentioned it on here, reading the tutorial it seems quite a powerful user friendly program.

Anyway hope all goes as well as can be expected for you, saying that by the sound of things it cant get much worse.
Regards

[Tinkerer]

Hi all,

here is my first effort to make a PCB for the Tinkerer_SB PSU&TX.
It is for 2x6V batterie and 50-cm roundcoil. The schematic is from http://www.geotech1.com/forums/showt...677#post155677 with some changes that tinkerer discussed with me. I send the PDF with this changes.

IT IS A TESTBOARD WITHOUT WARRANTY OF FUNCTION!!!

And it is my first time to make a pcb. I have not respected any rules of construction a low noise rig, or other rules for making a proper pcb. I think it can be improved a lot, so all comments to make it better are welcome.
[ATTACH]23412[/ATTACH]
[ATTACH]23414[/ATTACH]

Hi mschmahl,

congratulations for your excellent work on the board.

Here are some things to consider:

with everything working as it should, there can be an average current of about 3A in the coil and mosfet. This is the average, not the peak. therefore, a heath sink is recommended on the mosfet. Also check the TX traces on the board and the connectors, if they can handle 3A continuous average current.

The average coil current must not be confounded with the TX power consumption from the battery, which is normally about 60mA to max 170ma. The small consumption is due to the power recycling in the resonant tank.

The Flyback capacitors C1 and C6, must be high voltage capacitors. I have tried quite a few different kinds, but have not found any significant differences. Some of these are physically quite large, so enough space must be left.

For your purpose, a Flyback time of about 10us is probably ideal. This will need about 10+10n. I say about, because the coil inductance will vary depending on the wire you use and how tight you wind it and the capacitors have some tolerance, maybe 5% or 10% or 20%. All this is OK because we leave some leeway in the timing.

However, under the worst circumstances, the timing could be a little short. This would have the effect of increasing the power consumption quite a bit. The problem can be solved by adjusting the timing or by adjusting the capacitance.

All the best and good luck with the testing.

Tinkerer

[Tinkerer]

To all,
thanks for the good wishes and offers of help. My presence on the forum may be a bit erratic for a few months, but I will try to stay connected as much as possible to help with the design as much as I can.

Anybody's help, comments, constructive critic and advice with the design is most welcome.

Tinkerer

[Tinkerer]

You said you have a lot of power outages and overvoltages that take down appliances. If your hard drive died in one of these events and symptom is "no motor spin" it is possible your drive is ok. There is a TVS diode on each supply input. In such events one of these can short and cause this. Remove it and all is well but your drive really will die the next event unless you replace the TVS with another.

Hi bklein,
thanks for the help.
The LACIE external hard drive is powered with it's own PSU. The symptom is "no motor spin". The power ON diode blinks on the drive and on the PSU, like there is a power drop when the disk motor wants to start. For the time being I don't know yet if the PSU is working correctly or not. I will open the drive when I am settled in the new home and see if I can at least save the information on the disk.

Thanks for the advice.

Tinkerer

[sido]

Yes, it is DesignSpark! It is realy easy to learn and have a lot part´s. You can download missing part´s and it is all free.

Hi mschmahl,

First of all, well done on your first attempt at your designed board. Looks good.

Second of all, i listened to you and Tinkerer about designspark EDS and have downloaded the program.
Can tell you both that i like it so far.

Managed to figure out and import the Dispic4011 in the library which i want to use for the UNIPI. Took me a while, but figured it out.

Have a few questions???? about your board above you have designed.....When you have finished looking for errors and ready for the board to be made...Do you have to sent it out due to the complexity, like the inclusion of vias and also being double sided??

And how do you get to see the Negative artwork with designspark if you wanted to print it out for a single sided board. Have not looked through the full Tutorials as of yet, so asking as it may be something simple and that i may have missed.

Cheers Sid

[Tinkerer]

Sid,

when you have your schematics ready, go to TOOLS->TRANSLATE TO PCB
When you are satisfied with the PCB, go to OUTPUT->MANUFACTURING PLOTS

All the best
Tinkerer

[mschmahl]

@all
I have made some changes around C6, C1 and Coilconnection, but without heatsink for the mosfet (i don´t find one in libary). I think the best ist to solder the coil direct to board for handeling 3 A, therefore are the big pad´s. I have reconnect some part´s on the left, but i have to do it with the ride side.
Greetings from saxony.

[mschmahl]

New PCB for PSU&TX.
Further changes are: - R3 must be a big one with 3W
- Pinswap for -5V and +5V; sample #1 and sample #2; batterie 0V, 6V, 12V and Coilconnection
- allmost all track´s are on the bottom side, only 3 track´s are on top side, so the PCB can be made single-sided



One problem i see is on IC1, the LDO for + 5V supply. It is always on, because ground is 6V and in is 12V and there are no switches to turn off this IC. We could use an additional switch for batterie +6V.

Greeting´s from Saxony

[Tinkerer]

Hi mschmahl,

R 13 must be about 100 Ohm, 10 or 20 turns for fine adjustment.

R 6 is better about 47 Ohm, to limit the current that R13 sees. (R6+R13) should be between 47 Ohm and 150 Ohm.

All the best

Tinkerer

[mschmahl]

Thank´s Tinkerer.
Here is the updated file (only PDF). If someone need the schematic-file for DesignSpark PM me.
I´m soldering the RX-Board on a testboard. I think i will finish it today or tomorrow. Next step´s are programming the pic and building the coil.
For programming the pic i have PICKIT 2 and MPLAB IDE V8.50. What programm did you use? Is the HEX-file up to date?
Greeting´s from saxony.

[Tinkerer]

Thank´s Tinkerer.
Here is the updated file (only PDF). If someone need the schematic-file for DesignSpark PM me.
I´m soldering the RX-Board on a testboard. I think i will finish it today or tomorrow. Next step´s are programming the pic and building the coil.
For programming the pic i have PICKIT 2 and MPLAB IDE V8.50. What programm did you use? Is the HEX-file up to date?
Greeting´s from saxony.

I use the PICKIT 2 for the programming. Recently I am using MPLAB X. The V8.5 files run on X but I don't know if the other way around.
I have packed my stuff away for moving. In about 6 weeks I will unpack. In the meantime use the Hex file I posted earlier.
For the large coil and deep search, use about 20nF or 2x 10nF Flyback capacitor. This should work with about 10us OFF time.
Later we can optimize the timing for your specific purpose.
All the best
Tinkerer

[mschmahl]

Hello Tinkerer,
i have downloaded the MPLAB X but couldn´t use it right. Than i have downloaded PicKit2 Programmer. This was easier to use and i could programm the Pic16F690 with the notification: "successfully". How can i test the pic of proper working?

[Tinkerer]

Hello Tinkerer,
i have downloaded the MPLAB X but couldn´t use it right. Than i have downloaded PicKit2 Programmer. This was easier to use and i could programm the Pic16F690 with the notification: "successfully". How can i test the pic of proper working?

The TX pin should be ON about 90us and OFF about 10us. Sample 1 should be starting about 5us after TX OFF
Sample 2 should end just before TX OFF.

[mschmahl]

Sorry for my little report, but i have almost no time for my hobby these day´s.
The two board´s are now complete and all is wired good. The voltages are fine on the socket´s. The PIC is working right. I have made some scope-pictures
for TX ON and OFF and Sample 1 and Sample 2. I have take the probes for TX on Pin 2 of TC4452 socket and on Sample-connection-point on RX-Board.
Next step is building the coil.
Tinkerer thank´s for your tireless help.

[Tinkerer]

The timing is correct, congratulations!

If you crop the pictures, only to show the important part, they become clearer. Below is a link to a totally free software that works well for cropping and reducing the pictures for sending by WEB.

http://www.irfanview.com/main_download_engl.htm

Tinkerer