IC for driver 7 segment 4 digit

Discussion in 'General Electronics Chat' started by chichara, Apr 2, 2014.

  1. chichara

    Thread Starter New Member

    Apr 15, 2013
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    Dear all,
    Do you know what IC driver for 7 segment 4 digit?
    As i know for 7 segment 1 digit i can use 74LS47 and 74Ls192, or 4026.
    So for 7 segment 4 digit what shoul i use?
    is it possible to use 74LS47 and 74Ls192? i can figure it out for wiring.
    May be it silly question but I'm really new with electronics worlds.
    Thanks for your help.
     
  2. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    If you want to drive more than one digit, you will need to multiplex the digits using transistors.
     
    Last edited: Apr 2, 2014
  3. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi,
    You could use this IC, its available in CA, CC LED's and RTC and Decimal counts.
    E

    There are also the ICM 7211 and 7212
     
  4. chichara

    Thread Starter New Member

    Apr 15, 2013
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    Thanks for your reply :)

    @Dodgydave : did u mean besides the 74LS47 and 74Ls192, or 4026. i must add the multiplexer?
    If i want to use 4 digits, so what type of mux that should use? 8 to 1 or 4 to 1?


    @ericgibbs : Thanks for your answer. is it multiplexer IC? or just some function with 74LS47 and 74Ls192, or 4026 but used for 4 digits 7 segment?

    Regards,
    Chichara
     
  5. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    The ICM7217 is a complete counter/driver IC, did you read the datasheet I attached.?

    For reference the ICM7227 type is MCU compatible, 4 bit data bus plus control pins.
     
  6. takao21203

    Distinguished Member

    Apr 28, 2012
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    if you do an image search for this component then you can see it is totally obsolete.

    There is one listing on eBay- 1982 date code, 4 ICs, 15 dollar each.

    Are you serious about this advice? Do you use this IC?

    In my opinion this is a klunker from the year Anno Tobacco.
     
  7. takao21203

    Distinguished Member

    Apr 28, 2012
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    A simple microcontroller such as 16F884 can light up and control a 4 digit display without any extra parts. It is done with software.

    You can buy just a device programmer, and one IC, and you dont need any extra components. Only a row header with 5 pins, connect 5 wires, add one small capacitor.

    Power it from the device programmer.

    you can get PIC 16f884 as DIL IC + PICKIT3 clone (device programmer) on ebay, and that is it.

    http://aranna.altervista.org/dragon...ot-matrix-scrolling-message-14x5-source-code/

    Here you can see a 16f884 (as SMD chip). For 7seg, it is similar, but only 7 bars for each segment, not 5x7 matrix modules. It is simpler than text scrolling message.

    Nothing burns out and there are no problems at all, no batteries, no voltage regulators. Just no extra parts when you dont need them? There are other things to move on than 7seg displays.
     
  8. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    What chips are you using to count the digits with? if your using a micro like a PIC, then use multiplexing in the programming.
     
  9. crutschow

    Expert

    Mar 14, 2008
    13,033
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    What are you going to use as a source for the 4-digit number?
     
  10. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi
    I think your search engine needs a new battery...:)

    http://uk.farnell.com/maxim-integra...dwn-cntr-2mhz-28-dip/dp/2095868?ref=lookahead

    The Maxim version is still in production.

    http://www.maximintegrated.com/datasheet/index.mvp/id/1501
    E
     
  11. elec_mech

    Senior Member

    Nov 12, 2008
    1,513
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    As others have mentioned, this can be done with a microcontroller if a) you're trying to do with with as few IC's as possible and b) you know how to program a microcontroller.

    If you're looking for a purely hardware solution, look at the datasheet for a CD4553. It shows you how to use 2x CD4553, 2x CD4543, and a few other parts to control up to six digits. The CD4553 does this by multiplexing. This will only allow you to increment the digits (count up only).

    Another hardware option is to use a CD40110. One CD40110 will control one digit, so you'd need four CD40110's. This will allow you to count up or down.

    Either solution let's you use four IC's instead of eight to control four digits. The only caveat is both of these options only allow you to count - there is no provision for pre-loading or setting a specific value like you can with the '192. If you just need a simple count up or down display these will work nicely. If, however, you're building clock or something that requires any of the digits to be set to a specific value, then you'll have to stick with the '47 and '192 or similar.
     
  12. chichara

    Thread Starter New Member

    Apr 15, 2013
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    Hi,
    Sorry for my question if it makes you confusing.
    In this case i just want to use a simple methode without any microcontroller.
    i attached picture, in that picture, is it still possible to use same IC with the same schematic too? :confused:
     
  13. elec_mech

    Senior Member

    Nov 12, 2008
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    If I understand, you are asking if you can use a 4-digit multiplexed display with a '47/'192 circuit. Is this correct?

    The answer is no. The '47/'192 circuit is designed to drive each digit individually. To use a multiplexed display, you'll need a multiplexing circuit.

    To use a multiplexed display, you'd need to use the CD4553/4543 circuit or the ICM7217 IC ericgibbs mentioned. The ICM7217 costs a bit more, but it would take less board space and wiring. If you decide to use it, be sure to find out whether your display is common cathode or common anode and whether you want to count from 0000 to 9999 or if you want to count in time 00:00 to 59:59. See the first page of the datasheet to select the correct part number.
     
  14. chichara

    Thread Starter New Member

    Apr 15, 2013
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    @elec_mech : Yes, u're right! Oh, finally u make it clear. Thanks dude!
    I want to count from 0000 to 9999.
    So, i need multiplexing circuit with CD4553/4543 or ICM7217 IC right?

    My next question is: is it possible to use sensor (such a infrared or photoelectric sensor) as input counter with CD4553/4543 or ICM7217 IC?

    Thank you very much for your answer.
     
  15. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    You can use the 7217 as counter for sensor inputs, but the count input signal level must be at TTL or 5V CMOS voltages.

    Give us details of your IR sensor and we can suggest a simple amp or comparator circuit.
     
  16. chichara

    Thread Starter New Member

    Apr 15, 2013
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  17. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi,
    The output is open collector NPN or PNP depending upon the sensor type.

    So a pull up resistor to +5V would be used.

    Can you confirm is yours NPN or PNP type.?

    E

    EDIT:
    Looking in more detail at the specification in the link, it shows another 'output' which it states as solid state.??
    I cannot see any reference to this 'output' in the Specification Table
     
    Last edited: Apr 4, 2014
  18. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    Hi,
    Located the diagram on the sensor datasheet.
    The terms 'control output' and ' output' compared to the Spec Table and the d/s circuit are a little confusing.

    Look at this clip from the d/s. Its open collector as we said, either NPN or PNP.

    EDIT:
    Please advise type, NPN or PNP have a different solution.

    E
     
    Last edited: Apr 4, 2014
  19. chichara

    Thread Starter New Member

    Apr 15, 2013
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    Hi,
    The sensor type is NPN.

    I don't understand about this output, state or solid state. What does it mean? :confused:
    So, it mean that i can't say if the sensor output is 12V?
     
  20. ericgibbs

    AAC Fanatic!

    Jan 29, 2010
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    hi,
    As its NPN look a this image for details, use a 1K pull up to +5V, Black is Output

    EDIT: so the sensor output will bee TTL/ 5V CMOS levels.

    E
     
    Last edited: Apr 4, 2014
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