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daytimer
02-12-2012, 04:29 PM
I just got the latest rev 1.2 dc ssr boards from wjohn. I built one to spec but can't seem to get the mosfet to turn on. I have removed the voltage regulator and opto coupler, fed the board with 5vdc (using an atx power supply) and jumpered two of the pins on the opto socket to turn on one of the mosfets. Comparing the board to the data sheet for the mosfet, shouldn't the gate voltage be applied to pin 1? Looking at the board, it looks like the 5v gate voltage is being applied to pin 2 through the 470 ohm resistor with the 10k being used to bleed it off when turned off.
Without any pins being jumpered, the mosfet has 0v on the gate, 5v on the drain and 5v on the source. Jumpering a pin to "turn on" the mosfet yields the same results. I am using the FQPF13N06L MOSFET.

Henedce
02-12-2012, 10:50 PM
Check your 680ohm resistors . Sounds like the same problem I had last year and ended up being those I was supplied 680kohm instead of 680 ohm . Both read as .680 on my multimeter .680kohm and .680Mohm.

daytimer
02-13-2012, 11:15 AM
Well, I found that the traces on the board seem to be reversed. The trace off the opto goes to pin 2 on the mosfet and pin 1 on the mosfet is connected to the terminal block. The trace off the opto should go to pin 1 (gate) and pin 2 should be connected to the terminal block. I sent wjohn a pm to see what he thinks.....

jmksparks
02-13-2012, 12:17 PM
Well, I found that the traces on the board seem to be reversed. The trace off the opto goes to pin 2 on the mosfet and pin 1 on the mosfet is connected to the terminal block. The trace off the opto should go to pin 1 (gate) and pin 2 should be connected to the terminal block. I sent wjohn a pm to see what he thinks.....

Soldered the componets to the correct side of the board have we ???

daytimer
02-13-2012, 12:33 PM
Soldered the componets to the correct side of the board have we ???

yup. It wouldn't matter anyway.... The trace going from the opto to the mosfet goes to pin 2 of the mosfet. You can re-orient a 3 pin device any way you want and pin 2 will still be in the middle! So, the board feeds the voltage meant for the gate to the drain pin.
Attached is a pic of what I had to do to make it work. I cut the traces going to the 2 affected pins and rewired them according to the datasheet for the mosfet. The 1 port that is rewired works properly now.

13226

EasyGo
02-13-2012, 01:52 PM
Wow, you're right -- looks like that board was set up for DGS pinout on the MOSFET (like the little TO92 ones) instead of GDS (left-to-right) like most power MOSFETs use. Anyone else using version 1.2 (a?) DCSSR boards?

daytimer
02-13-2012, 02:37 PM
This guy http://www.mouser.com/ProductDetail/Supertex/TN0604N3-G/?qs=sGAEpiMZZMsrr1kXJis%252bJx8EKuMrsj0gqrY1DWE5a% 2fY%3d is a 7a DGS pinout. It should work for what I plan on doing. I wasn't sure if there were different mosfet pinouts or not. I guess that answers that!
I wonder if Radio Shack would have it? bwahahahahahah!!!!!!! :freak:

BOM needs to be updated in the wiki!

EasyGo
02-13-2012, 03:49 PM
This guy http://www.mouser.com/ProductDetail/Supertex/TN0604N3-G/?qs=sGAEpiMZZMsrr1kXJis%252bJx8EKuMrsj0gqrY1DWE5a% 2fY%3d is a 7a DGS pinout. It should work for what I plan on doing.

I think the Mouser catalog is a bit misleading on that one... it is rated for a max continuous current of 0.7A, 4.6A pulsed (with the duty cycle presumed low enough to not overheat it). Also, you need to swing the gate 10V for that kind of current (the chart looks like it'll do 2A peak with 5V of gate drive). Note that you'd also have to install it facing the opposite direction as the original design.

TN0604N3-G datasheet (http://www.onlinecomponents.com/viewer.aspx?p=12649279&Resource=1)

Good luck!
Jon

daytimer
02-14-2012, 06:25 PM
The only thing the local radio shark had was some mps2222a's. They are max 600ma. My dc loads were going to be around 400ma max. That's cutting it awfully close, but I'll see how it plays.
I really wish I could find something heftier that would solder right in without any modifications.....

EasyGo
02-14-2012, 07:24 PM
Unfortunately, that MPS2222A is a regular bipolar transistor instead of a MOSFET, though it might actually work for your purposes, if you're lucky on the gain of the transistor :closedeyes:

After some searching, I didn't turn up much in the way of power MOSFETs with SGD or DGS pinouts... here's one with SGD pinout that's 1.2 amps & 50 volts, 0.3 ohms Rds, that might work for you as long as your current stays below that:

VN3205 at Mouser (http://www.mouser.com/ProductDetail/Supertex/VN3205N3-G/?qs=sGAEpiMZZMsrr1kXJis%252bJx8EKuMrsj0gQToFjJXi9B Q%3d)

This is not going to be a generic solution for those of us that ordered DC SSR boards intending to draw several amps, though :ohmy:

dlovely
02-14-2012, 07:28 PM
The only thing the local radio shark had was some mps2222a's. They are max 600ma. My dc loads were going to be around 400ma max. That's cutting it awfully close, but I'll see how it plays.
I really wish I could find something heftier that would solder right in without any modifications.....

Just a heads up, the Ren48LSD uses the MPS2222's and has 48 400mA outputs.

daytimer
02-15-2012, 09:02 AM
Just a heads up, the Ren48LSD uses the MPS2222's and has 48 400mA outputs.

that's where I got the idea to try it. How are the earlier boards set up? With that part listed in the wiki bom, I can't imagine others haven't had this issue.

dlovely
02-15-2012, 11:22 AM
that's where I got the idea to try it. How are the earlier boards set up? With that part listed in the wiki bom, I can't imagine others haven't had this issue.

Did you ping John about it? If you look at the WiKi the pins chanded between versions. The new one on DIYLEDExpress matches the first version and what you had to modify this one to.

daytimer
02-15-2012, 02:17 PM
I did ping John about it. Other than cutting the traces, he doesn't have any other immediate solution. I asked him if he plans on updating the board to work with these mosfets.
I couldn't find the board wiring for previous versions, so I was wondering if it had somehow changed. I figured if it was this way on previous versions, somebody would have picked up on it.

LabRat
02-15-2012, 02:26 PM
Did you ping John about it? If you look at the WiKi the pins chanded between versions. The new one on DIYLEDExpress matches the first version and what you had to modify this one to.

Where in the WIKI are you seeing the pinout change? I've looked around (more than once), and all I found were the schematics. The symbol for the MOSFET changed a little bit, which leads me to think the new part may be mis-labelled in the library. (Just conjecture.. no direct proof). Are there pictures of the underside/layout anywhere?

dlovely
02-15-2012, 02:38 PM
Where in the WIKI are you seeing the pinout change? I've looked around (more than once), and all I found were the schematics. The symbol for the MOSFET changed a little bit, which leads me to think the new part may be mis-labelled in the library. (Just conjecture.. no direct proof). Are there pictures of the underside/layout anywhere?

Version 1.1 (http://www.doityourselfchristmas.com/wiki/images/0/09/DCSSR_Sch_1.1.pdf) - Pin 15 from the Opto goes to bottom pin of the MOSFET

Version 1.2 (http://www.doityourselfchristmas.com/wiki/images/8/81/DCSSRv1_2.pdf) - Pin 15 from the Opto goes to the center pin of the MOSFET

Maybe John had changed the BOM to use a new MOSFET and not updated the Mouser BOM to reflect his change to the design.

EDIT: This was my post 666. LOL

LabRat
02-15-2012, 03:02 PM
Hmmm... I didn't consider those symbols as having pin markings. To me that simply showed connection to the GATE pin, which on the new library symbol, mapped to the wrong pin for the devices listed in the BOM.

g2ktcf
02-15-2012, 03:03 PM
Hmmm... I didn't consider those symbols as having pin markings. To me that simply showed connection to the GATE pin, which on the new library symbol, mapped to the wrong pin for the devices listed in the BOM.


I agree Andrew...I have emailed John for an explanation. I too see an issue here.

dlovely
02-15-2012, 03:06 PM
Hmmm... I didn't consider those symbols as having pin markings. To me that simply showed connection to the GATE pin, which on the new library symbol, mapped to the wrong pin for the devices listed in the BOM.

Yeah understood, but when you look at the PCB pictures posted in this thread you can see it goes to the center pin. If you look at the data sheet (http://www.fairchildsemi.com/ds/FQ/FQPF13N06L.pdf) for the MOSFET the center pin is not the gate.

LabRat
02-15-2012, 03:12 PM
Understood. I'm all "eagle" based, so I don't know how all the other systems/software does it. If this error happened under Eagle, I would say almost certainly that there was a mis-alignment between the library symbol, and the library part. As the symbol in the schematic changed between 1.1 and 1.2, it is my conjecture that something similar happened here. I hope that either
a. Not too many PCB's were made or
b. A source for MOSFETS with the alternate pinout can be identified.

Modding a bunch of boards would be a pain.

BRETT
02-15-2012, 03:52 PM
I too have the same problem. Discoverd it last night after buying 100 mosfets. I purchased the rfd14n05l fet not awre that the pinout on the fet is different to the board.
I now have 48 boards with that are usless without modification. Frustrated.

g2ktcf
02-15-2012, 04:17 PM
I too have the same problem. Discoverd it last night after buying 100 mosfets. I purchased the rfd14n05l fet not awre that the pinout on the fet is different to the board.
I now have 48 boards with that are usless without modification. Frustrated.


Brett,

Where did you get the PN to order? I am trying to track down what is going on here as these are the ones I am going to be stocking in my online store.

Chris

g2ktcf
02-15-2012, 04:18 PM
Brett,

Where did you get the PN to order? I am trying to track down what is going on here as these are the ones I am going to be stocking in my online store.

Chris


Also, do not modify the board just yet as John says this is the wrong part......

BRETT
02-15-2012, 04:21 PM
Purchased from rs online

BRETT
02-15-2012, 04:23 PM
Rs Part No. for mosfet is 3257580

g2ktcf
02-15-2012, 04:47 PM
hang on you misunderstood the question....

Where did you get THAT part number from?

EasyGo
02-15-2012, 05:39 PM
http://www.doityourselfchristmas.com/wiki/index.php?title=4_Channel_DCSSR_Assembly_Instructi ons#PCB_Overlay_Version_1.2


The original MOSFET used was a STF20NF06 and here is the datasheet. The original MOSFET was plastic tab isolated.

an optional part is the Mouser, RFD14N05L, as part # 512-RFP14N05L and here is the Datasheet

Even though the part in the Wiki is RFDxxx and the link RFPxxx, they should interchange for most purposes as the pinouts are the same (G-D-S). The RFDxxx is in a smaller TO-251 case where the RFPxxx is a TO-220 case.

None of these parts is going to work without modifications on the board pictured in daytimer's post.

g2ktcf
02-15-2012, 06:19 PM
http://www.doityourselfchristmas.com/wiki/index.php?title=4_Channel_DCSSR_Assembly_Instructi ons#PCB_Overlay_Version_1.2



Even though the part in the Wiki is RFDxxx and the link RFPxxx, they should interchange for most purposes as the pinouts are the same (G-D-S). The RFDxxx is in a smaller TO-251 case where the RFPxxx is a TO-220 case.

None of these parts is going to work without modifications on the board pictured in daytimer's post.

That is what I am looking for....I will get back with you on this. There is actually a third one listed in the Mouser BOM link. So give me a a bit to sort this out.

wjohn
02-15-2012, 08:18 PM
Hi,

I was contacted yesterday about this issue, I'll be home tonite and will check the files. If a mistake has been made, I'll replace any and all 1.2 V boards with a new board at my cost.

The production house lost a server and my V1.1 files were lost, so we quickly knocked up a V1.2 file and added a fuse as it had been requested by a few people.

I dont want anyone to be out of pocket if it was my mistake. as for the Wiki, I'll also check and update as over time there can be changes to parts availability that I am not always aware of.

Thanks for letting me know, and I'll look to get this fixed ASAP.

LabRat
02-15-2012, 08:22 PM
It doesn't get more straight forward than that!

(What a great bunch of folks)

g2ktcf
02-15-2012, 09:34 PM
I just got off the phone with wjohn....there is a mistake in the boards as he mentions. We are working on getting them replaced as soon as we can.

BRETT
02-16-2012, 01:46 AM
Glad to see this sorted out.
Si if a new board has to be designed and manufactured can I make a suggestion.
I thought that an LED on the board to show 5 volt of the regulator would be good or some test points.
I know there is a led for incoming but would be good to know your 5 volt regulator is working.

LabRat
02-16-2012, 09:23 AM
This is already in place in the DCSSR available through DIYLEDEXPRESS. I will be posting the gerbers to the file share.
(Tried the other night, but kept getting an error).

wjohn
02-18-2012, 02:03 AM
I have made a number of modifications,

The board is now capable of 10 amps!! double sided, Plated thru holes. Channel ratings are now at least 3-4 amps per channel (there is a lot of copper)

I can add a second LED (optional) to show that the 7805/78L05 is functioning.

I have sent the PDF to Chris for checking, I want to make sure that his standard parts will fit.

I'll post the 1.3 (c) version with the second LED after supper.

BRETT
03-12-2012, 10:11 PM
Does anyone know if the new layout for this board was finalized?
Have tried contacting wjohn several times but he must be busy.
Just need to know if they have been put into production and if the parts list from the wiki will still be the same.

kychristmas
03-12-2012, 10:37 PM
My guess if there is, Chris (wlcventures) will have it available. He works pretty closely with wJohn


Does anyone know if the new layout for this board was finalized?
Have tried contacting wjohn several times but he must be busy.
Just need to know if they have been put into production and if the parts list from the wiki will still be the same.

BRETT
03-12-2012, 11:01 PM
Tried contacting about this with no response either.....
A year goes real fast in blinky flashy world

daytimer
03-13-2012, 04:36 PM
A year goes real fast in blinky flashy world

Yes it does!
At least for those of us who have the incorrectly screened board, I thought he was going to send replacements as soon as he had them made. I don't know how long they take to have made, but I have a lot of building to do to be ready for my first blinky flashy year!

BRETT
03-14-2012, 01:24 AM
Finally got in contact with John. He expects the boards to arrive some time next week, hopefully.
As soon as he gets them I am sure he will ship them out.