LM8560 Digital clock circuit diagram with alarm

LM8560 is digital clock circuit IC that electronic amateurs are most interested. And The clock ICs that most popular are LM8361, MM5387, Unfortunately, these ICs looking for will be difficult.

I highly recommend this clock circuits features to work for less than the original circuits. But there are advantages due to having output in Duplex LED display model, so reduce the number of wires between IC1 (LM8560) and LED display was 2 times more than the original.

Note: Also this projects we can use Jumbo digital clock using simple CMOS ICs

The clock working

In this circuit, the heart of the circuits are IC1 (LM8560), Which has output the 3 way are:
1. The output for drive display Duplex Model numbers (pin 1-14)
2. The output provides alarm signal at pin 16.
3. The output to control electrical appliances with automatic timer.
Two R1, C1 together with was integrating circuit to Provide input to the clock signal 50 Hz input lock pin (pin 25) of IC1.

LM8560 24hr digital clock

Two diode D1, D2 are the switch signal generators to the cathode of display number for working alternately and relation with the input of IC1. The alarm signal from pin 16 of IC1, will be entered to the potentiometer P1(Volume), to pin 3 of IC2 (LM386), that is alarm signal amplifiers to drive the loudspeaker.

The P1 so is fine an alarm sound pressure as you want. And the sleep out signal from pin 17 that you can continue to use, to control another circuit.
how to set the time
1. Press the switch S6 to set hours.
2. Press the switch S4 to set minutes.
To set the alarm time
1. Press the switch S3 to hold down.
2. Press the switch S5 to set hours.
3. Press the switch S4 to set minutes.
When the time limit, the alarm signal will ring. Press switch S2 or other switches to stop the alarm sound.

– Cancel the alarm system, press S2 to hold down.
To set the time turn on- off the Electric appliance.
1. Press switch S6
2. Press switch S4 to set minutes, Time to show the remaining time.
3. Press switch S5 to set hours.
Time dilation alarm to repeat alarm.
In the case of alarm circuit operation and we want to Repeat alarm. To extended for another nine minutes, with the press of a switch S7. The output signal for control turn on-off electric appliance circuit, get from pin 17 of IC1.

PCB of Cheap Digital time clock with alarm circuit by LM8560
Figure 2 The PCB layout of Cheap Digital time clock with alarm circuit

components layout of digital clock using LM8560
Figure 3 The components layout of this projects

Detail of parts
D1, D2, D3_1N4001 50V 1A Diodes
0.25W 5% Resistors
R1_100K 1/4w resistor
R2, R3_120Ω
Volume P1_10K Potentiometer
C1, C5_0.01uF 50V Polyester Capacitor
C2_470uF 16V Electrolytic Capacitors
C3, C4_0.1uF 50V Polyester Capacitor
C6_10uF 16V Electrolytic Capacitors
C7_100uF 16V Electrolytic Capacitors

Buy LM8560 Here

Builds LM8560 clock circuit

-You place the electronic components on the PCB board correctly completed, as shown in the picture, The display numbers can use bent wire to perpendicular. Then soldered directly to the PCB and LED display.
Note: PCB layout print in 300 dot per inch
-These switches you are able to put directly on PCB.
-You can choose display is 12 hours with open pin 28.
– If you want to connect a battery backup to the circuits continues to operate, even when the power goes out. You just connect the 9-volt battery, by the negative terminal join to diode 1N4001 into pin 20 of IC1 and the positive terminal at pin 28.
-To work range power clock cycle will continue. But it will not display on the screen.
-If do not has the backup power supply when the power goes out then restart display circuit will blink.

We recommend these below

LM8365 alarm digital clock for beginners
Jumbo digital clock using simple CMOS ICs
Time based clock generator using crystal for digital
MM5369 60Hz calibration frequency

Related Posts


I always try to make Electronics Learning Easy.


  1. Ajoy kumar sinha

    this digital clock uses 50 Hz house supply line as time but in case of power supply failure it will not work.if a CRYSTAL oscillator is used with circuit it will be most usefull.

  2. Samad Bond

    Hey please send me the original pcb layout file i want to build the clock like yours.I shall be thankful to you.Have a great day…!

  3. michael cruz

    hi! can i have a copy of the program? please. thank you in advance

  4. Shawn


    This looks really interesting. Can you send me a copy of the PCB layout?


  5. Jared Ireland


    I am a 14 year old boy and i am making this project for a school assignment as well as a birthday/Christmas present.

    In the 1st picture i want to know, what S1 is? and where it is placed in the PCB?


  6. john

    hi, where can i get the duplex display? looking for one right one.. please let me know asap.. anybody?

  7. Chin

    Dude..!! What is the purpose of LM386 in this circuit. Is it capable of driving speaker for speaking clock….!???

  8. Diodeman

    How can we place am/pm indicator in this circuit

  9. Diodeman

    How can we use this circuit to display seconds in numbers instead of two dots.

  10. N.Lekshmanan

    the above digital clock circuit easy to understand at the samme time the parts are available in the market i need this clck please sent its price thanking you

  11. Akhil kumar T

    what is the power rating of transformer t1. is it 9-0-9
    . The switch s1 is missing. Is it power on/off switch
    in description u said that “If you want to connect a battery backup to the
    circuits continues to operate, even when the
    power goes out. You just connect the 9 volt
    battery, by the negative terminal join to diode
    1N4001 into pin 20 of IC1 and the positive
    terminal at pin 28”
    I think +ve terminal join to diode and -ve to 28.
    isn’t it..?

    please give me a replay.. i wanna do this thing..

  12. Sujjwal

    Please give the pcb layout size for printout on glossy paper.

  13. sammycage

    please i need the pin confirguration of the duplex display 🙂

  14. Ng Zhun Khai

    No40,Jalan5,Taman Sungai Mas,34000 Taiping,Perak

  15. Ng Zhun Khai

    Can i know where to buy duplex display in malaysia

  16. dinh

    can you tell me where to get the duplex display please? my search didnt come up any information about this part.

  17. sand

    would this circuit work on 5v and how much power
    it consumes.

  18. yonko

    i found duplex display but it 20 leg???

  19. habib

    how about the pcb size generally . pls tell me.

  20. KH

    what other displays could be used with this?

  21. sandip karmakar

    I have prepared one for me … I just want to add 20 LEDs/segment of the display. I have seen if I put 5 LEDs/segment, then I get desired luminosity /brightness from the LEDs, But if I increase the number of LEDs/segment, then it wont glow . Might be due to voltage drop. Please suggest what can be done in this scenario.

  22. Askar Alibolandi

    Hi.i,d like to add a regulator ic to the clock diagram because when ac220 v of the city is weak,the clock doesn,t work correct

  23. Hi Askar Alibolandi,
    Thanks for your question.
    I am sorry, this circuit needs AC line to generate a DC pulse 50HZ.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.