Author Topic: DNA 30 Base for easy installation (Read 60045 times)

Breaktru · « **Reply #50 on:** September 08, 2014, 06:40:00 AM »

Please! NO SELLING OR MENTIONING SELLING OF COMPLETED MODS ON THIS FORUM.
Boards and parts for DIY projects are okay to post.

miskol · « **Reply #51 on:** September 08, 2014, 09:07:37 PM »

TQ guys, tq very much for the compliments

i assembled the first piece and spent around 1 week troubleshooting, thinking the design has flaws (it was auto-firing when atomizer connected), apparently i was just unlucky to assemble the 1st board with a manufacturing PCB defect.

however the Charger IC is hot, i asked in a different thread and Craig mentioned that his charging IC have an exposed pad, i used the same IC(MCP73833) but without the exposed pad which unfortunately my local supplier doesnt supply that exposed-pad version... i thought i would like to confirm that the IC really couldnt be used for 1Amp charging even with multiple vias and dual layers to dissipate the heat, so yeah it is confirmed lol. i'm gonna assume that this IC is not suitable for small-design and space limited applications without the exposed pad type.

in a few days i will get a new charging board that will be using a different charging IC with the exposed pad (MCP73113), hopefully it is a good alternative IC to the MCP73833 and the exposed pad would solve the heat issues. if it turns out to be ok, will use it on the new revision for this V3.

other than that, i was also thinking to add LEDs for each buttons, not really sure if there's any space though haha, maybe need to use smaller 0603 LEDs.

CraigHB · « **Reply #52 on:** September 08, 2014, 09:28:08 PM »

The charger controllers do have to dissipate some heat. You've got a maximal differential of USB voltage minus battery voltage which can be up to 1.5V (including some voltage drop due to the charging connector and cable). At a 1 rate, that's 1.5W on the controller, a lot of heat for a little chip like that.

In any case, you should have no issue with the exposed pad part. If you put some vias on the thermal pad connecting to a ground plane, it will dump the heat no problem. On my own boards, the chip can normally tolerate the differential with no thermal limiting. For a fully discharged battery, it has to run for a little bit in thermal limiting, but it only slows down a couple hundred mA and runs up to full rate pretty quick once battery voltage comes up a bit.

I normally use the 0603 LEDs, they're not too hard to work with and peform well enough.

miskol · « **Reply #53 on:** September 09, 2014, 04:23:23 AM »

thanks Craig, now i fully understand why there's that much heat, the voltage differential, the same case with voltage regulators.

CraigHB · « **Reply #54 on:** September 09, 2014, 06:54:13 PM »

If you want to get fancy, you can use a charger controller that employs a DC-DC converter. That will greatly reduce heat production and may even allow a higher rate than 1A. Those losses that go into heating the chip for a linear controller can be utilized to increase the rate instead of making heat. There's a range of USB charger controllers that utilize a converter, not a big one, but they are available.

miskol · « **Reply #55 on:** September 09, 2014, 07:35:34 PM »

did a quick search, went through a few ICs and saved MAX8903A for this type of high-charging lesser-heat charge controllers.

the IC's price sure is fancy too haha, 6 times more expensive for this 2Amp charge controller, its a 28-pin package and requires a sizable high Isat inductor but this makes an interesting next project to do

CraigHB · « **Reply #56 on:** September 09, 2014, 07:46:46 PM »

Yes, big overhead on those in terms of cost and PCB real estate, that's why I don't use them. Though if you have the room on your PCB, it's worth the overhead to eliminate that big source of heat production.

Mev · « **Reply #57 on:** September 11, 2014, 08:58:55 PM »

some excellent profesional boards there mate, very nice job.

miskol · « **Reply #58 on:** September 19, 2014, 06:26:21 AM »

thanks Mev

holding on the works on these DNA base, currently doing and testing my own DC-DC Booster circuit. am i permissible to create a thread for sharing the progress and my miseries hahaha. of course hoping for discussion and comments regarding it.

we have a small vapefest here soon, would like to bring it there hehe.

TiGG · « **Reply #59 on:** September 20, 2014, 11:01:57 AM »

@miskol
Are you planning to release the PCB layouts? I would really like to build a few for myself and family.

T8ternutz · « **Reply #60 on:** September 22, 2014, 11:06:33 AM »

this would be awesome to have the layout for the V3.. that's a beauty..

blank · « **Reply #61 on:** December 12, 2014, 05:47:16 AM »

Awesome. I myself have been trying to make a reasonably small mod but never thought to make PCB to slap the DNA on to. Any plan to make one for DNA 40? No need for some of the built in safety stuff...

Suzukiv6 · « **Reply #62 on:** December 18, 2014, 06:04:16 PM »

You have made an excellent job of your design, so compact and really professional. I would love to build a mod around one.

miskol · « **Reply #63 on:** December 23, 2014, 03:10:51 PM »

Quote from: TiGG on September 20, 2014, 11:01:57 AM

@miskol
Are you planning to release the PCB layouts? I would really like to build a few for myself and family.

probably, haven't really been able to design the PCB so that it could handle the maximum amp and output maximum wattage previously. the V3 can only output approximately 20W, higher than that the DNA30 will restart, because of space constrain it is the same as like using small cables for the power lines (battery input & DNA output).

I have also produced PCBs for the DNA40, but it is a custom-design for a modder/mod. there's some design mistakes but a little modification and it works fine, there's no additional circuits on the PCB so there's sufficient space for the power lines thus able to support the DNA40's output.

the V3 have been upgraded for the DNA40 too, should receive the PCBs within this week, hoping that it will work well.

bfu9278 · « **Reply #64 on:** December 26, 2014, 03:10:16 AM »

Nice....so when the other one will appear here...mr mc?do the oled come in already...?

miskol · « **Reply #65 on:** February 10, 2015, 09:57:18 AM »

mC D40 V3

Dimension: 25.4mm by 77.2mm
Features:
- DNA40 removable slot
- Fire/Up/Down tactile button
- Fire indicator (blue LED) or connections for illuminated switch (with on-board resistor)
- Rev Polarity indicator (red LED)
- Keystone Holder 1042
- USB Charger (up to 1Amp)

miskol · « **Reply #66 on:** February 10, 2015, 10:01:07 AM »

Quote from: bfu9278 on December 26, 2014, 03:10:16 AM

Nice....so when the other one will appear here...mr mc?do the oled come in already...?

appeared

i waited to share with others first, got their feedback that it is working nicely before sharing here.

yeah i have my OLEDs in already for some time but i got weird problems. will share on the other thread later.

miskol · « **Reply #67 on:** February 10, 2015, 10:04:43 AM »

apparently i still have heat issues with chargers that i built, even though this one have exposed pad at the bottom of the charge controller, the same model used by Craig.

CraigHB · « **Reply #68 on:** February 11, 2015, 01:33:22 AM »

Hmm, shouldn't be running in thermal limiting. Are you sure your solder joint is solid with the thermal pad? I usually can get a 1.2V differential between battery voltage and USB input voltage without thermal limiting. Keep in mind there's usually some drop in USB voltage over the line. I actually tune my adapters a bit so I get about 4.6V at the chip under a 1A load, those are line losses. Adapter voltage is 5.1V open circuit. That chip won't run much over an Amp. You can get it up higher if you run the adjustment resistor down, but then it's always running in thermal limiting.

mrbump82 · « **Reply #69 on:** February 11, 2015, 11:51:13 AM »

I need one of these

Spiceman · « **Reply #70 on:** May 08, 2015, 07:31:57 AM »

Quote from: miskol on July 14, 2014, 12:32:18 PM

seems like i found a nice board mounted connector, i tried to find the bolt and nut that could fit the solder pad, but couldnt.

bought it from Farnell

Awesome work sir! I have been looking for this type of board to board connector to handle the DNA40 loads. What is the part number of the ones you found at Farnell? They look like they work great.

miskol · « **Reply #71 on:** May 08, 2015, 12:01:53 PM »

that pin has no spec, i just assume it is rated for at least 11Amps based on its dimension (20AWG). so it fits nicely with DNA30 pin holes and DNA40 smaller holes but not the bigger holes (for 18AWG). also i abused the pin, used it in reversed position

not so easy to solder them in place to slot the DNA boards.

i suggest you consider using this spring loaded contact pin, fits the DNA40 big holes, through-hole and higher amp rating.
http://my.mouser.com/Search/ProductDetail.aspx?R=100891-002virtualkey53060000virtualkey818-100891-002

Spiceman · « **Reply #72 on:** May 10, 2015, 04:31:29 PM »

Quote from: miskol on May 08, 2015, 12:01:53 PM

that pin has no spec, i just assume it is rated for at least 11Amps based on its dimension (20AWG). so it fits nicely with DNA30 pin holes and DNA40 smaller holes but not the bigger holes (for 18AWG). also i abused the pin, used it in reversed position not so easy to solder them in place to slot the DNA boards.

i suggest you consider using this spring loaded contact pin, fits the DNA40 big holes, through-hole and higher amp rating.
http://my.mouser.com/Search/ProductDetail.aspx?R=100891-002virtualkey53060000virtualkey818-100891-002

Thanks for the information!