Picture of Dot Matrix Business Card
If my flashlight business card isn't advanced enough for you, then how about one with a full graphical display on it that can be customised for a number of scrolling messages? This one could be made in quantity for about a $5 parts cost, and it is only a little bit more expensive if you are making just a few. I won't kid you that this is an easy design to make - don't try it unless you have very good soldering skills and some experience in electronics. Some of the components here are smaller than grains of rice, so it would be useful to have good eyesight as well! Like the flashlight card, it is more of a proof of concept than something you can churn out in quantity, but it might at least give you an idea of what can be achieved, and where business cards might be in just a few years time.

Step 1: About The Design

Picture of About The Design
This is the sort of card that would suit a high-tech business, or those who were involved in high-value contracts, where an innovative image is all important. I would never suggest that it would replace a conventional business card, but to impress that all-important prospective client, there would be more than a few companies who would be happy to spend just an extra few dollars. Like the flashlight card, the aim is to design a business card that people just can't throw away!

The design is really quite simple for what it does - a matrix of 5x15 LEDs, connected to a single-chip "PIC"microcontroller. A handful of resistors and switches complete the design (Schematic available below). By keeping the microcontroller in sleep mode unless the buttons are pressed, the battery can last several years, and still allow a couple of thousand displays of your messages.
MatrixSchematic.pdf(595x842) 101 KB
yaly2 months ago
You can also use jumper resistors or "000" value smd resistors to connect the horizontal lines and have some traces running under the LEDs.
KellyKandy3 months ago

Great idea

i want to make this, but i don't want to use surface mount, i.e. normal LEDs, batteries. so what components should i use. please help :(
Fayez slim2 years ago
yes i know i check but the battery holder in the double sided pcb
tomward (author)  Fayez slim2 years ago
Hi - the one in step 2 is 18-3780 from rapidonline.com. The one referred to in step 7 was just a couple of bits of wire soldered in - it wasn't a proper battery holder.
Fayez slim2 years ago
plz upload a photo of it or his name to buy it plz
Fayez slim2 years ago
and sorry for my question but i have another one what is this type of battery holder in the new pcb
tomward (author)  Fayez slim2 years ago
Hi - if you check step 2 of the instructable it lists the parts and suppliers
Fayez slim2 years ago
if i want to write my name and my email plz tell me how
my name is fayez slim
and my email is fayezslim@hotmail.com
plz reply
tomward (author)  Fayez slim2 years ago
Hi - if you check step 5 of the instructable it will tell you how to spell out messages
Fayezslim2 years ago
can i use your hex file in matrixcode.zip with out editing it plz reply
tomward (author)  Fayezslim2 years ago
You are welcome to but it won't be much use for you as it will have my name and email on it rather than yours!
india57853 years ago
I am looking to build the same circuit but modify the program. I have run into a road block trying to get a PCB manufactured. My education hasn't covered creating Gerber files and such... Is the PCB simply 2 layers?
tomward (author)  india57853 years ago
It is actually only 1 layer - very simple. Best bet to do it commercially is to find someone who accepts an Eagle ".brd" file which is attached to the instructables
DUDE !!!

Seriously awesome stuff ! Many thanks for showing exactly how this is made with VERY - Clear & concise pictures and steps!

Also interested in your MK 2 version with colour OLED screen!

Undoubtedly Awesome & is every possible meaning of my words!

You're A Genius! Simply-Said !
nerd74733 years ago
where did you get the parts?
check out step 2
farzadbayan3 years ago
Very interesting!
CHANNIHONEY3 years ago
channihoney says:
how can write new message this display ?
I've made a few of these already, they have been working great :) I've also recently started working on a completely flush version, which will hopefully be just as thick as the pcb... All the components are sunk in, except for the LEDs! Thank you so much for this amazing Instructable, you've given me hours of trial and error and most of all a chance to learn about smd soldering and programming :)
aessam13 years ago
i really like it
it's very well designed
and i really like the idea for the overlay
very nice....
good job pal
got an idea tom to revise the board. Where the Battery is placed cut out a hole and place the battery in the hole, and use tin flaps soldered to the board. That will make it thinner.
yakteeno4 years ago
How can I make one of these
mangomango4 years ago
im really interested in making this into a portable sound analyzer. like a SpeaQualiser. anyway, i was wondering just how durable this is and size comparisons. like would i be able to keep this in my wallet?
volkee4 years ago
May i make this commercially in Thailand?
Just using the idea, not the whole thing.
tomward (author)  volkee4 years ago
Sure - the information is freely available so go for it. Send us an image of what you come up with if you get one up and running - would be interested to see.

shaf7895 years ago
i dont no how to re name?
It's not becouse you make It in a Mac? I use only Windows, i never tried Mac. Anyway I opened It with Notepad of Windows and It says this (a little part): €B | < ÎëH§(ƒ x ™ G©Í ü>€ÂFˆÊ ü>€ÂFˆÊ ü>€ÂFˆÊ ÿ š™™™™™©?š™™™™™™? Top Bottom Pads Vias Unrouted Dimension tPlace bPlace tOrigins bOrigins tNames bNames tValues bValues tStop bStop tCream bCream !" tFinish "! bFinish #$ tGlue $# bGlue %& tTest &% bTest '( tKeepout (' bKeepout )* tRestrict *) bRestrict ++ vRestrict ,, Drills -- Holes .. Milling // Measures 00 Document 11 Reference 22 dxf 34 tDocu 43 bDocu 56 tGND_GNDA 65 bGND_GNDA 87 wert [[ Nets \\ Busses ]] Pins ^^ Symbols __ Names `` Values aa Info bb Guide d Muster ee Patch_Top ff Vscore hh Name tt Patch_BOT yy _tsilk zz _bsilk —— HeatSink ÈÈ 200bmp ÉÉ 201bmp ÊÊ 202bmp úú Descript ûû SMDround þþ cooling P - ««‡ ¸ ó € \ Lightbox E þÿsë ÐqfSO28W +€ &ïþÿPLÿÿ¸ø* 2 +€ Ú PLÿÿ¸ø* 13 +€ Š½þÿPLÿÿ¸ø* 1 +€  ÿÿPLÿÿ¸ø* 3 +€ ^RÿÿPLÿÿ¸ø* 4 +€ vB PLÿÿ¸ø* 14 +€ >ß PLÿÿ¸ø* 12 +€ ¢­ PLÿÿ¸ø* 11 "€ '‘þÿxæ þn xæ ç "€ 'þn ˆÿÿ‘þÿˆÿÿç "€ '‘þÿˆÿÿ‘þÿxæ ç "€ 3„a xoÿÿ|žþÿxoÿÿø "€ 3|žþÿxoÿÿ|žþÿ ƒÿÿø "€ 3|žþÿ ƒÿÿ|žþÿˆ ø "€ 3|žþÿˆ „a ˆ ø "€ 3„a ƒÿÿ|žþÿ ƒÿÿø 1€Š½þÿœ1 Î >NAME +€ –µÿÿPLÿÿ¸ø* 6 +€ jJ PLÿÿ¸ø* 9 +€ úƒÿÿPLÿÿ¸ø* 5 +€ 2çÿÿPLÿÿ¸ø* 7 +€ | PLÿÿ¸ø* 10 +€ Î PLÿÿ¸ø* 8 "€ 3„a ˆ „a ƒÿÿø "€ 3„a ƒÿÿ„a xoÿÿø 1€Š½þÿÈœÿÿÎ >VALUE"€ 'þn xæ þn ˆÿÿç +€ vB °³ ¸ø* 15 +€ Ú °³ ¸ø* 16 +€ >ß °³ ¸ø* 17 +€ ¢­ °³ ¸ø* 18 +€ | °³ ¸ø* 19 +€ jJ °³ ¸ø* 20 &€ 3÷³þÿ00ÿÿÇþÿkÿÿ &€ 3“åþÿ00ÿÿ¹øþÿkÿÿ &€ 3/ÿÿ00ÿÿU*ÿÿkÿÿ &€ 3ËHÿÿ00ÿÿñ[ÿÿkÿÿ &€ 3gzÿÿ00ÿÿÿÿkÿÿ &€ 3¬ÿÿ00ÿÿ)¿ÿÿkÿÿ &€ 3ŸÝÿÿ00ÿÿÅðÿÿkÿÿ &€ 3; 00ÿÿa" kÿÿ &€ 3×@ 00ÿÿýS kÿÿ &€ 3sr 00ÿÿ™… kÿÿ &€ 3¤ 00ÿÿ5· kÿÿ &€ 3«Õ 00ÿÿÑè kÿÿ &€ 3G 00ÿÿm kÿÿ &€ 3ã8 00ÿÿ L kÿÿ &€ 3ã8 q” L ÐÏ &€ 3G q” m ÐÏ &€ 3«Õ q” Ñè ÐÏ &€ 3¤ q” 5· ÐÏ &€ 3sr q” ™… ÐÏ &€ 3×@ q” ýS ÐÏ +€ Î °³ ¸ø* 21 +€ 2çÿÿ°³ ¸ø* 22 +€ –µÿÿ°³ ¸ø* 23 +€ úƒÿÿ°³ ¸ø* 24 &€ 3; q” a" ÐÏ &€ 3ŸÝÿÿq” ÅðÿÿÐÏ &€ 3¬ÿÿq” )¿ÿÿÐÏ &€ 3gzÿÿq” ÿÿÐÏ +€ ^Rÿÿ°³ ¸ø* 25 +€  ÿÿ°³ ¸ø* 26 +€ &ïþÿ°³ ¸ø* 27 +€ Š½þÿ°³ ¸ø* 28 &€ 3ËHÿÿq” ñ[ÿÿÐÏ &€ 3/ÿÿq” U*ÿÿÐÏ &€ 3“åþÿq” ¹øþÿÐÏ &€ 3÷³þÿq” ÇþÿÐÏ Üÿÿ$ õ rf +€2 pÆ Ä°' P$1 +€2 8c ÄÄ P$2 +€2 ÄÄ P$3 +€2 ÈœÿÿÄÄ P$4 +€2 9ÿÿÄÄ P$5 4ÿšÿÌ f #rf "€3Èœÿÿ8c 8c 8c { "€18c 8c 8c Èœÿÿ{ "€08c ÈœÿÿÈœÿÿÈœÿÿ{ "€2ÈœÿÿÈœÿÿÈœÿÿ8c { +€ ,kÿÿˆ; œ1Î P$1 +€ ,kÿÿxÄÿÿœ1Î P$3 +€ Ô” ˆ; œ1Î P$2 +€ Ô” xÄÿÿœ1Î P$4 mþmþ““ 2rf %€ 3 ö ö { *€ Š½þÿŠ½þÿˆ POS1 *€ vB vB ˆ POS2 *€ Š½þÿvB ˆ NEG1 *€ vB Š½þÿˆ NEG2 (€ ø* € led íÿÏÿ 1 Lrf?rf +€ L    C +€ ´âÿÿ   A &€ 3lîÿÿ” ” 4! &€ 3lîÿÿÌÞÿÿ” lîÿÿ "€ 3`ðÿÿ” `ðÿÿlîÿÿü "€ 3  ”   lîÿÿü &€ lîÿÿ Hôÿÿ¸ &€ ¸ ” ¸ &€ $úÿÿ Ü ¸ 1€2çÿÿ2çÿÿÎ >NAME And I can't change the name, in properties and when I download It, says: Downloading FJ57QXVFT3K2QPS.tmp... Did you tried to download It in your PC? It's really strange. Now I use Windows 7
tomward (author)  Gonzalo Ruiz5 years ago
After renaming, you will need Eagle PCB (Free download) to view and edit the PCB file.
Hi in the step 8, the download link is naemd 'Led Card.brd' and when I download It it´s named 'FJ57QXVFT3K2QPS.tmp'. Why It´s different?Why the format is '.tmp' in stead of '.brd'? Please help me.
tomward (author)  Gonzalo Ruiz5 years ago
Strange - didn't use to do this - tried uploading again and same thing happened. You will need to rename the ".TMP" file to ".BRD" after you have downloaded it - google "Change File Extension" if you need to know how to do this. This is a newer version of the PCB file - a double-sided one with no need to use the "mock double sided board" trick with the sticky tape. Apologies, but no longer have the original board.
samr37l5 years ago
 Where did you find the library for the led's? I can't seem to find the library....
tomward (author)  samr37l5 years ago
There is no library needed - all code is in one file attached to the instructable.
samr37l tomward5 years ago
 Yah, but I would like to design my own. (Yours is just WAY to complicated for me, but it is REALLY cool)
satadru5 years ago
hi...i jst gng to start wth pic mic.can u tell me which book is good to guide me properly with pic microcontroller........
tomward (author)  satadru5 years ago
Sorry, but don't have any books on PICs - just done a search on "PIC Microcontrollers" on Amazon and their looks like to be a good few for beginners with good reviews - perhaps someone else can recommend one?
glocketz6 years ago
Hey, Sunstone circuits (custom pcb manufacturer) requires the matrix to be in either a .RAR, .123, . BRD, or .BIN formats. Can you please upload a copy of the matrix in one of those formats so I can have a circuit printed? Thanks.
tomward (author)  glocketz6 years ago
I have loaded an Eagle .BRD file on the last step of the instructable, but it is slightly different - see the comments on the last page.
l4a tomward5 years ago
Hello, I have a bit of a problem. And  I'm asking for a help. I have succesfully soldered everything and programmed it. But it doesn't work as it should. When I insert the battery all the LED's are turned on. Even if I press one of the four switches nothing happens (all the LED's are still on). Could you help me with the problem, please? Thanks
tomward (author)  l4a5 years ago
Hi - sorry, but it is pretty near impossible to troubleshoot remotely without access to the circuit.  My best guess is that the program is not running at all - perhaps due to an incorrectly programemd fuse/option bit.
l4a tomward5 years ago
Hi again. I'm new in this and I'm having some troubles understanding your solution. Could you please tell me where can I select this fuse/option bit?
Thank you for your time! I really appreciate it.
tomward (author)  l4a5 years ago
Looking at the source code again it looks like I put the fuse options into the source code in the first few lines so that shouldn't be a problem.  I would suggest programming my original hex file (from the the zip) - if this works then it is a change you made to the code that stopped it working.  If it doesn't then things get harder to work out and it must be in the hardware.  Let us know how you get on.
l4a tomward5 years ago
Well I haven't been able to fix it so I decided ti make another one. And even this one doesn't work. I have checked all the connections and everything seems OK. So is it possible that I have overheated the PIC while soldering?

p.s. Is it possible that you could send me one of your prototypes? I would pay you of course.

tomward (author)  l4a5 years ago
Hi - really sorry, but only ever made one and this disappeared somewhere when being shown at a maker faire in the US.  Are they programming/verifying OK?  If so then you prob haven't blown up the chip - I think that they are less sensitive these days to heat/static etc than they used to be.  Send me a private message with your email address and I will try to help if I can.
l4a tomward5 years ago
I think I might have solved the problem. I don't know how I did that but I turned the LEDs up side down! This week I'll try to do another one and I'll tell you the result!
stan45 years ago
You totally got me!
I was totally curious to see what was the part number of the display, hahahaha, very nice work!

I gave you 4.5 stars because I don't think the card is waterproof.
codongolev5 years ago
this might be a stupid question, but how does the microcontroller drive a single LED at a time?
tomward (author)  codongolev5 years ago
The LEDs are arranged in a matrix, with outputs driving every column and every row.  To target a single LED you just turn it's row output high and it's column output low.
so.... another stupid question.... does high mean it's giving off power and low mean it's ground? I think that's my understanding of it, but I might be wrong....
tomward (author)  codongolev5 years ago
That's right - if both outputs are low (or both high) then the LED would be off.  In this card I control a whole column of LEDs at a time by pulling their column pin low (whilst all the other columns are high), and then setting the row pins to control particular combinations of LEDs in that column.  Then we move on to the next column, etc.  Thius cycling of the columns happens so quickly that they eye doesn't see the flickering (like watching a movie).
alright. persistence of vision and all that. I see.
there is no such thing as a stupid question
I'm sure I could think of some.
Aye but it would not be stupid
Ward_Nox5 years ago
be neat to make a deck of playing cards using something like this (you won't know what cards you have till you hit the button)
kinetickt5 years ago
Could you make and program them for someone for a fee? 
tomward (author)  kinetickt5 years ago
Hi - sorry, but I'm not doing these commercially  In small quantities they take quite a bit of time to make up so are not really cost-effective to make.
shmuley955 years ago
 gr8 ible ! ide love to see how thin it is tho. perhaps post another photo? a comparison to a business card and to a credit card would be nice!
tomward (author)  shmuley955 years ago
Sorry but don't have this one with me any more - it never came back after going to a Maker Faire somewhere!  Think it was around 6-7mm, although potentially could get it down to around 2-3mm with redesign.
dagenius6 years ago
You should seriously make a buisness card mp3 player--just to make apple jealous!
yes ,have you seen buisness cards with a built in usb key
USB Buisness cards: One Credit Card Company gave away some mock credit card 2GB USB flash drives for promotional purposes. (Look for them on E-Bay: "USB Flash Drive".)

If you were in the software buisness you could use such USB Flash Card/ Buisness Cards to give away sample versions of your software up to say 1GB leaving the rest for recipiant use.
Or a Stock Broker could give them away loaded with stock market historical data with a short program that would bring the data up to date with automatic downloads from your web site.
I think that larger USB Flash Cards of up to 32 or 64 GB are possible for a higher price.
Being something useful it will stay in the walet not the desk drawer and keep your name in the recipiant's mind.
with a built in speaker! ;)
l4a5 years ago
Hi, I made one of this yesterday. And after programming it succsessfully, all the LED's are on. What could be the problem?
salemance255 years ago
very cool i made like 30 of these and theyre relatively easy to make
very nice work. congratulations and thanks for sharing it with us!
keastes5 years ago
i might have to adapt this into a digital glowstick.
4 patterns without a reprograming.
all my base are belong to you

ErisOnline5 years ago
Could I potentially use this model to make a really tiny clock?
 Great Idea.
You can try it commercially
a solar panel would be kinda a bad idea as this is a BUSINESS CARD...maybe for another reason?
kotarski5 years ago
Stick a solar panel on the back. That might work.
kotarski5 years ago
Ever thought of sticking a solar panel on the back?
whoop_john5 years ago
Well executed project, but you could take advantage of charlieplexing and address up to 90 LEDs with just ten output pins rather than 20.

OK, the wiring matrix will be harder to do, but it is possible. I have charlieplexed 144 leds from one pic with no problems at all, see http://www.clock-it.net/led_clocks/charlie4.html
tomward (author)  whoop_john5 years ago
Could do, but the PIC I used is one of the cheapest ones so you wouldn't save a lot, and I have a simple mind so it was easier as well to programme! Awesome clocks though - love the circular PCB artwork.
Many thanks for your kind comments. Your concept is very cool and well executed. I like it very much. Well done that man. I am working on a magic trick right now where space is important, especially thinness. I am also using a lithium, but I am going to drill a big hole so that it can sit within the PCB, with a contact either side. This will shave some width off. I think you could do this with the leds and even the PIC - sink them into the PCB. When I get some time I might follow this idea up, with due credit to your good self, of course. PICBASIC makes it trivial to program PICs.
tomward (author)  whoop_john5 years ago
I did a version of this card for someone else recently that sunk the cell in like you mentioned (by the way, thin electric guitar strings work quite well as contacts - they have the strength and springiness of steel but can be soldered). Although you embed the PIC if I ever made these commercially (very unlikely), I would prob get one of the low profile surface mount PICs and a thin PCB (I sometimes get 0.5mm boards made up for prototypes)- together with low profile LEDs the thickest bit would still be the battery. You have me curious now agbout the magic trick - is magic a hobby?
Cubie25 years ago
Ward_Nox6 years ago
I could see alot of tech ppl getting cards like this
you could make it much thinner by simply doing to the LEDs what you reccoment doing with the battery and using a button like those found in disposable camera flash triggers, as well as embedding a thinner battery. that would make it about as thick as the thickest component in the board.
dillon66676 years ago
dude you should patent these!
rteeuwsen6 years ago
While good in theory (looks cool, probably useful for marketing), it is an absolute waste in terms of being enviromentally sustainable. PCSB (Firbeglass), copper PCB tracks, batteries that have many unfriendly components....... You're obviously a smart guy/girl, use your intellect for something of true benefit! just takes a bit of perserverance!
hey no need to preach man we hear bout the environment every day on TV.
tomward (author)  rteeuwsen6 years ago
Always said it was a concept to get people thinking rather than something I am suggesting would be given out like conventional cards. Would like to think as a teacher I am doing something of benefit ... apologies for taking a few nights off to contribute something to the maker community ...
ralegg tomward6 years ago
Don't listen to the nay-sayers, I think this is a great showing of technical ingenuity! It's teachers/professors like yourself that inspire students (or the rest of us on instructables) to think big. Efficiency? This is a fusion of art and technology if you ask me! Again, great job!
! xD !6 years ago
Phew, nice job, looks cool! I couldnt make one, since I barely know a lick about electronics. xD Still, its a neat futuristic lookin' card, but with a sense of something new and innovative. Again, nice job, looks tight! -xD
oric116 years ago
yeah their right it quite understandable unlike those other d.i.y. it so complicated
how many leds are there i think i read 600 and somethink but i diddnt realy kno if it was it??? can u just give me the number of them?????????
tomward (author)  james.mcglashan6 years ago
5 rows of 15
so 75..
how thin is it???
tomward (author)  james.mcglashan6 years ago
Don't still have this one in my hands but think it was around 6-7mm or so. Just working on one for someone else that is around 5mm. Could go down to around 2mm with off-the-shelf components, but would need quite a bit more redesign.
you could easly make the board with micro componets on a super smail pcb...
and get it about the size of a half a mm added in total
tomward (author)  james.mcglashan6 years ago
It's not as easy as it sounds - tricky to get it much below 2mm when you take into account the thickness of the chip, and particularly the battery - hard to get battery below about 1.5mm by itself if you want to draw enough current to operate the LEDS. If money is no consideration and you go into thin film batteries, etc, then you could go fractionally smaller ...
no battts and use a mini cap and sola charger...
tomward (author)  james.mcglashan6 years ago
Thin solar cells are available, but super caps tend to be quite bulky and would make the card thicker.
i mean a cap that is a compleate flat cap...??? would that work then nd it might work on only the panel without a new flat cap.. p.s the flat caps are so new i dont blame for not knowing i only found outby an email but i deleted it by mistake when i ment to delete a other message. and the thin solar pannel can go on a smail dock with the contacts being copper so u can put them all on a dock and get a little power like maby enough to charge batterys for project for the futcher... lol that will work so good as a free battery charger lloll
legionlabs6 years ago
This would be nice on double sided flex-PCB!
glocketz6 years ago
Can you please elaborate on this step?
tomward (author)  glocketz6 years ago
Really we are soldering some horizontal wires across the board to conenct the components. The tape is just to insulate the copper traces underneath from touching the wires. You may find it useful to download the image and then zoom in a little with a graphics programme to see how it works. From your comment elsewhere about a PCB it looks like you are getting one commercially made - in this case you can probably dispense with the tape as a commercial board will usually have an insulating "Solder Mask" over the copper tracks. Also the ".BRD" file I have uploaded in step 8 is actually a double-sided one, so this whole step using the tape/wire won't be needed, but as mentioned in this step, there have been a couple of other changes as well, so check out the last paragraph of step 8 carefully.
Great idea for a card! I wouldn't want to give it away unless it was a guaranteed sale though~!
collard416 years ago
what do you use for PCB design? great instructable 5* favourited
tomward (author)  collard416 years ago
Ultiboard is better, you can drag and drop the components onto a PCB, then it will Autoroute them for you.
kravikula7 years ago
I just think blue LEd will be better looking. but is a great idea.
tomward (author)  kravikula7 years ago
Blue is nice but has a higher 'voltage drop' - you would probably need two battereies rather than one, and they are quite a bit more expensive.
Evan606 tomward7 years ago
How would a green LED hold up for this? Like how many more batteries (if any) do you think it would use
tomward (author)  Evan6067 years ago
Fine - Red, Yellow and Green typically have a low voltage drop of around 2V, but it does depend on the model - the green ones can have a drop of up to 4V, which wouldn't work - look for ones which have a drop (or "forward voltage", often called Vf) as low as possible. You also want bright ones as well, and these two specs sometimes conflict with each other.
wicked! could i buy one and if so how much?
tomward (author)  quazzamuhaha6 years ago
It is really only a prototype - would need to produce them in large batches to make it worthwhile commercially, as they are very time consuming to assemble.
Hi, if you plan to commercially this cards, please contact me. Maybe we can share the costst.. With www.easy2reach.com everybody canb exchange vCards by 1 sms. Combining a good message to a led busineescard can make it more special.. (example: sms vcard sven to 1008) only in hollan.
I just finished building 10 of these, yes they do take a while to assemble.
Pauper6 years ago
Quote "Next, I would like to work on a high-resolution version using a colour OLED display - think photographs and animations. The sky is the limit - almost any electronics could be put into business cards - wireless links, audio soundtracks..."
And eventually, you'll end up building a PDA ... easier to just buy one.
Yeah, but then building it yourself is waaaaaay more fun innit???
BuildWiz6 years ago
This is really cool! I was thinking you could make it more advanced is that you could make it have wi-fi and then show temp. and weather conditions. Just an idea for anything in the future.
macgeek106 years ago
A very ingenious design you have come up with there for your ad hoc 2nd layer i thought of that a while ago and implemented it on a larger scale (16 x 24) led matrix, but it looks like you have the programming skill and also the time to get your design up much faster, all i have built is my display :-\
Wonderful Work! Congratulations!
asturias746 years ago
Good job Could I buy two hands like yours? I have feet at the end of my arms..... too much difficult!!
munchman7 years ago
Wow! that is amazing. 5/5 stars. How would you expand this to use more LED's?
tomward (author)  munchman7 years ago
You would prob have to go for a PIC with more pins and have more rows and columns.
Brett_cgb7 years ago
First! Consider using a device with an internal clock source - this eliminates the need for external timing components, and often frees up the OSC1 and OSC2 pins for other purposes. A 40-pin device would allow 7 or 8 rows and more columns - this makes for a nicer, more dense display. Consider modifying the code to allow serial insertion / extraction of the ASCII text to be displayed. Code would need to map each character to the required bit pattern.
tomward (author)  Brett_cgb7 years ago
Very valid points, but all of these decisions were done to minimise cost - updating LEDs is not timing critical (and besides, a single R/C costs only a couple of cents) - the primary cost is LEDs, so I actually wanted to reduce the rows to 5. You certainly could make versions more advanced or higher resolution, but for this exercise I wanted to make the cheapest possible design that could display legible messages. Although mapping ASCII codes directly would make programming easier, the way it is done is not hard to set up, and allows you to program non-text graphics, change inter-character spacing, etc.
Jouda Mann7 years ago
Congratulations, you got hack-a-day'dhack-a-day'd
Sphelx7 years ago
raykholo7 years ago
can u make like a 5th spacebar style button below the display so it can show the time or something like that? kinda cool to have that feature
tomward (author)  raykholo7 years ago
No reason why not - the sky is the limit - you could definitely make it more functional like some of my other designs - perhaps some arrow keys and implement a game on it related to the business?
now thats cool and can you make one for like personal features that doesnt advertise anything? just a heads up for the top 5 things u might need or something like that
FREAKIN' COOL!! I gotta try this.
crreed7 years ago
what kind of soldering iron is good for SMD
ANY! SMD are actually super-easy to solder, so long as you have a steady hand and something to hold the components in place. I suggest finding an iron with a sharp tip, and perhaps search for some "How to solder SMD components" instructables.
I'm going to make one of these in the next few days I'm just waiting for the parts to arrive..

This is just awesome

Also there are these switches which are about 2 millimeters thick which you could use for the next type with the smaller inlaid battery

Thanks for this great Instructable
could you make it a mini tv???
tomward (author)  AnarchistAsian7 years ago
The technology is just about there, but battery life would be a problem and it would be very expensive. I would like to do a color OLED screen version though that could do promotional pictures/animations/videos etc.
use a mini 12 volt battery
wow!... too expensive...
this looks great. i would have made the screen smaller though because i find it hard to read with that few characters on the screen and also a wheel on the side that could speed it up or slow it down would be cool.
F1X0R7 years ago
www.Rapidonline.com FTW!
merseyless7 years ago
if I got one of these business cards i would buy whatever it displayed... except for personal jets. !!! a business card with a jet in it! ...a new frontier in business card design...
neardood7 years ago
thats really cool but the technology isn't just limited to business cards...
This is very cool. I would definitely like to try making one.
LinuxH4x0r7 years ago
Wow, I want one of those! Very nice 5/5
jeff-o7 years ago
Very impressive! I especially like your ad-hoc double sided PCB, and the clever way you used a printed transparency as the top layer. Another thing you could try is using an LCD screen instead of LEDs - not as shiny (and I do love shiny things) but the battery life will be that much longer.
Costs will skyrocket!
Very Cool! Looks Great!
louisgoo7 years ago
Nice idea m8 . I think i would be cool to make one on a belt you could have random messages looping round you
that exists
Kiteman7 years ago
mattlilly7 years ago
This is a great idea. You should be able to get angel money to further play with the concept. For those who do not have soldering skills you can get free business cards at <a rel="nofollow" href="http://bizcard.com">http://bizcard.com</a> . <br/>
Nukewarm7 years ago
Did anyone else think this guy made a replica of Dot Matrix's business card (Delivery service?) from the tv show Reboot?
pstretz7 years ago
super awesome. a little hard to put in a business card scanner though. :-) a mini usb connection to flash containing a vcard or textual contact info or something would be a great addition. great job again, really like this a lot!!
ConcorX7 years ago
Wow thats amazing!
ironsmiter7 years ago
WOW... just WOW.
Nicely done.
and a beautiful solder job/board layout.

"Firstly I would change the CR2032 cell to a CR2016 as this is thinner, and then embed it within a space cut in the PCB. By using lower-profile components, the thickness of the card could probably be reduced to about 1/8th of an inch (rather than the current 1/4 inch)"

If you're going to inset the thin battery in the pcb, consider also insetting the switches and the chip( "professional deadbug soldering? ;-)

For the "ugly but effective" idea of what I am referring to, see http://www.instructables.com/id/USB-Li-ion-battery-charger/
but applied to your design, with the pretty circuitboard.
gmjhowe7 years ago
wow, alot of work gone into that, im very impressed! keep up the good work!