Picture of Big 7-segment Digital Clock
Using only 2 capacitors, 3 resistors, 4 BIG seven-segment Display, 1 xtal, 2 switches ,and 1 Microcontroller PIC, you can build this Digital Led Clock main circuit.

you can use common anode or common cathode display, just select the display type. Here is the pinout information:(I have attach the all diagrams of parts and 7 segments)

I'm used 4x 6" big 7 segment display's.

​Ok now everyone who need this kit buy over here:

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Step 1: Simple paper copy schematic

Picture of Simple paper copy schematic
here is the schematic and part list for the project.

IC - PIC16F628 / PIC16F84A

Step 2: Collect your parts:

Picture of Collect your parts:
7 segmants.JPG
4x  6" big 7 segment display
3x 10K Resistors
2x  tack switches (micro switches)
4MHz Cristal (XTAL)
2x  22PF

If you are planing to protect your IC you should connect the IC through 5V regulator (1x 7805)

Vero baord(I used dot matrix board)

and other 7 Segment driver circuit parts displayed with attach image.

Step 3: Solder your all parts

Picture of Solder your all parts
part side.JPG
7 segment.JPG
board back side.JPG
segmant . driver.JPG
Solder your all parts on to your vero board matching with this Circuit diagram.

Please do not solder your PIC16F84 on your board.Fix that through 18 pin IC base or Zif socket. 

Step 4: Make your enclosure

Picture of Make your enclosure
box 1.JPG
clock inside.JPG
2  buttons.JPG
Make a enclosure box  for clock.(makes with plastic acrylic sheet + glue) 

and completed circuit board and 7segment board fix on your back plastic acrylic sheet.

and fix the Hour and Mins adjusting button to your enclosure right side panel.

Step 5: Programe your PIC16F84

Picture of Programe your PIC16F84
I have attach the HEX (16F84 clock) file for this clock.You have to burn it into your chip well.
TrishiaI2 months ago

can you send me the list of the entire circuit diagram including the power supply?? and do you have a hex for pic16f87??

0987652 years ago
Can you send the list of the entire parts and entire circuit diagram of big seven segment clock to email below.
slwthr (author)  0987652 years ago
please download the full project Clock.rar file in this page..Thanx!

hello slwthr, please help me get a pdf or details of how to build the 7 segment digital clock. this is ma email: ......thank you!!!!

slwthr (author)  DawnComeaux1 year ago

Ok now everyone who need this kit buy over here:

ecinev4 years ago
hey..what about the hex code
ecinev ecinev4 years ago
(removed by author or community request)
slwthr (author)  ecinev4 years ago
Cool :)
ecinev slwthr4 years ago
hey.. we're asked to built the same circuit in the josepino.. i tried your hex but it doesn't fit. .... Do you have the hex for it??? 2 capacitors, 7segment anodes, 10k resistor, pic16f84a, 2 switch... can you help me?? please...
slwthr (author)  ecinev4 years ago
which display size u used? Big 7 segments or small one? Microcontroller Circuit is just simple like this.(From Josepino) but If you are using Big 7 Segment you must have to build Transistor array(darlington) like this diagrams.then couple with microntroller out puts to Big 7 segment display's.

Does your 7 segments displays any thing??
ecinev slwthr4 years ago
small one...but the display is incorrect..
slwthr (author)  ecinev4 years ago
please give me your email address,will massage you this clock modified version without transistors.(with darlington array IC control)
ecinev slwthr4 years ago
(removed by author or community request)
slwthr (author)  ecinev4 years ago
your welcome. I will send it soon.

hi can u help get a detail of to build the 7 segment digital clock.......this is my mail acct;

ecinev slwthr4 years ago
(removed by author or community request)
slwthr (author)  ecinev4 years ago
u mean hex for this clock?? I have sent email yesterday,and find the attached zip file of Big Clock schematics and hex code). (from my hotmail : so what diagram you want???
ecinev slwthr4 years ago
i'm trying your hex for this diagram....just this diagram
ecinev ecinev3 years ago
sorry for late thank you's...thanks again for helping me.. problem solved?!
hope you can help others as well.. :)
ecinev slwthr4 years ago
i'm trying your hex for this diagram...just this diagram....
cali909 slwthr3 years ago
Hey wass up brother, man! that is a great digital 7 segment clock. I am interested after taking my first intro. class of engineering and about to complete my programming class. Arduino can I have a copy of you schematic and programming layouts to apply practice in my field.


ozbone21 year ago

can anybody send me a pdf on dis 7 segment digital clock, please!!!

natasha1461 year ago
is there any reason why you use a950 and c1815 transistor?can i replace it?
slwthr (author)  natasha1461 year ago
No special reason for C1815 but I used A950 because its a darlington transistor which came in small package.. You can replace it
moustick1 year ago
Thank you for your wiring, it help me in my design of my big clock also. I was stuck with the multiplexing the 12V led segments, great instructable
slwthr (author)  moustick1 year ago
Your welcome you moustick
aressar1 year ago
hello , bro can u plz send me the ciruict diagram along with the pic program for big 7 segment clock on my email id....
oman11 year ago
Helo sir, can u please send me the MicroC files for Big 7 segment clock.

sislam71 year ago
Hi, please send the details for Big 7 segment clock.
(with hex file)
rafanun3 years ago

can you send me full details of this clock?
slwthr (author)  rafanun2 years ago
please download the full project Clock.rar file in this page..Thanx!
slwthr (author)  rafanun3 years ago
Sent a new design with hex code
Can you please send me the full details of this project with a proper circuit diagram ?
Have you .hex File for PIC16F628
slwthr (author)  asankasrimal2 years ago
Sorry!I heven't
ramesh773 years ago
Hi im interested on this very much.....can you please send me the circuit diagram and the .hex file if using PIC16F628A??
slwthr (author)  ramesh772 years ago
I don't have one for one with 16f876
dansan1013 years ago
Hi, im looking at replication this and i was wondering if you could tell me where you got the 7 segment displays, and if you could send me any of the relative informtion on the circuit. Cheers dan
slwthr (author)  dansan1013 years ago
Here is the link for Large 7 Segment Display..Bit expensive than in Sri Lanka market.

And sent the mail with new design!
gonzaled133 years ago
Can you send the list of the entire parts and entire circuit diagram to email below.
I only have 4 pcs. of 3 inch displays, will the clock work if I use them instead of the bigger displays.

slwthr (author)  gonzaled133 years ago
Sent a new design with hex code
bita983 years ago
Hi, can u please send me the ciruict schematics and help me about how to connect the 7 segment displays to my microcontroller? I am using Bare_Bones Board as my microcontroller and was trying to use 74hc595 bcd, but my clock doesn't work.... Could u please help me
slwthr (author)  bita983 years ago
Dear friend,I haven't try any microcontroller circuit using "Bare-Bones Board"..I only used PIC microcontroller and assembly or C compile software's. But Bare-Bones Board has a Atmel chip and its own software nah.

Why your clock not working? what trouble you guess? what schematic you want?
Shabbar3 years ago
sponcio3 years ago
hi sir! can you pls help me to do a 7 segment clock (the small one like a match box) i just need the seconds .. what IC and schematic diagram will I going to use ??
hi bro i'm doing my 3rd yr ece but doesnt knw the basics but i like to do this clock so plz help me bro give me guidance and sent all the info of this clock to me
dhudzs3 years ago
can you send me full details of this clock,
hi send me full details of this clock,
slwthr (author)  saqlainmushtaq3 years ago
yixiong.863 years ago
Hi, Can also send me "" thanks
slwthr (author)  yixiong.863 years ago
Sent a new design with hex..
Robomind3 years ago
hi plz mail me the he code i hav to try its nice

mail id:

slwthr (author)  Robomind3 years ago
hey bro can u plz send me the ciruict diagram along with the pic program on my email id....
slwthr (author)  nikhil.patankar3 years ago
Can u plz send the full circuit to me in mail

slwthr (author)  albinvadakkekara3 years ago
Check your mails.I have sent the mail with attachment.
smorad4 years ago
hye arduino.. nice clock! actually i want to ask you on how to do a digital alarm clock. it is my project actually. i have created my pcb and have troubleshoot it, but it doesnt work.. i have try it for many times. i have used 3 latch and 1 buffer which is 74574 and 74245, 4 seven segment, resistor, buzzer, capacitor, transistor, decoder 7447. i dont know how to check the part where have a problem. can you please help me. =)
slwthr (author)  smorad4 years ago
hey..Thanx a lot :).Ah nice Idea and I have some design for alarm digital clock.when I finish the schematic drawing i will post it.and i have som other schematic which i have found from other site.I will send it to u. You tried for Big 7 Segments or Small one's?? Me too got a lot problems when using big 7 segments.Coz of 7 segment working power and current problems. but now its bit solved.hope i can help you.Do you have any schematic of your circuit?
smorad slwthr4 years ago
welcome =) i tried for small 7 segment. when i trobleshoot my pcb, it show negative result. how sad.... =( you mean pcb circuit ? yes i have one.
slwthr (author)  smorad4 years ago
No worries :) ah that's good first you should try with small one then can develop to a big one.Like can develop for Big 7 segments with Darlington array (ULN2803 and UDN2981) I have correct Circuit and schematic for this darlington array big clock.I can mail you these clock schematic and hex file for you.Please inbox your email. what you mean by troubleshoot your pcb? you tried with your own pcb design? didn't you check weather your circuit works or not on any project board?? Want to see your clock circuit design and code..if you can mail me please. =)
smorad slwthr4 years ago
ouh.. i will send you my schematic but can you give me your email?
slwthr (author)  smorad4 years ago
hey I have sent you da massage.please check it .did you got ma massage?
leon3854 years ago
i have tried eveything but your version doesn't work
leon3854 years ago
on your segment drive circuits Qa is c1815; Qc is A950; what is Qb . And must i build 4 of the first circuit and 8 of the second to drive 4 displays
krusty4 years ago
Credit where credit's due...
slwthr (author)  krusty4 years ago
the control circuits given by Josepino all are Common for most of the usual Led clock Circuits.I have used 6 inch big 7 Segments.So I have used different driver stage unlike josepino.Anyway thanx for the comment.
krusty slwthr4 years ago
And you've used his hex code, too....

Like I said - credit where credit's due.
slwthr (author)  krusty4 years ago
Yeh 100% agree with you :)
aasif.faiz4 years ago
Cool, harith ayya did ya sell the car oc thing u put up on ebay?
slwthr (author)  aasif.faiz4 years ago
thanx i didn't malli.I will put it soon again.coz hav some modifications.:)
prash_thil4 years ago
gotta try this at home!!!!!!
i have never tried programmin a pic before
Gotta Try this
slwthr (author)  prash_thil4 years ago
good idea.try try!!I have uploaded all the details with hex file for PIC16F84A.Hope you can work this out well.Good luck!