ULN to be used with LED display

[thelma]

uln with lcd

does uln2003 requires any particuylar Ic to drive a 7 segment display in common anode...

 

[FvM]

uln with lcd

A 7 segment common anode LCD display?

If possibly mean a LED display, you only need current limiting resistors for each segment in addition.

By the way. You're apparently new to edaboard. Please take at look on the rules and points chapter, particularly regarding unwanted crosspostings.

 

[thelma]

uln with lcd

yes am very much new to edaboard.i'll surely look thro wat yu said.

mean while i meant lcd display only. as yu said if i use limiting resistors fr each led,i could hardly make only one digi display & my design is going to end up simple.just try to help me of wat IC i can use to display a digit in 7 segment display in common anode mode..plz

 

[howie]

Re: uln with lcd

May I know on what particular circuit will you use the said component?

I have a suggestion that you try CA3162 and CA316E. It is a monolithic A/D converter that provides 3 multiplexed BCD output. CA316E is an LCD driver that can be applied in using LCD (refer to page 5 from the attached datasheet). The attached datasheet will show you application circuit for LED, 7 segment and LCD.

Find attachment below to know more about it.

 

[pranam77]

uln with lcd

I am confused wether u are refring to LCD display or LED display?...anyways..ULN is a darlington arrangement inside and will drive a seven segment LED display directly through its outputs when the inputs are supplied with "Hi' logic. You may also have a look at the datasheet of ULN for more details. Cheers

 

[thelma]

uln with lcd

pranam i'm very much clear that using uln2003 ,we can driver seven segment led's but wat if the display which am using is common anode??is it possible??
and can you tell me how to arrange 4 seven segment displays.
for example if am going to use 4 uln's and 4 sets of 7 seg led's, how can i interlink the design in order to make my process to work using my synchronous and asynchronous commands.

 

[pranam77]

Re: uln with lcd

pranam i'm very much clear that using uln2003 ,we can driver seven segment led's but wat if the display which am using is common anode??is it possible?? and can you tell me how to arrange 4 seven segment displays.
for example if am going to use 4 uln's and 4 sets of 7 seg led's, how can i interlink the design in order to make my process to work using my synchronous and asynchronous commands.

As the outputs of ULN is "Low" you have to use Common anode displays. The connection for 4 displays is as given in the schematic. Cheers

 

[thelma]

uln with lcd

pranam the lcd displays which you ve send in the JPG file is bcd to 7 seg right??

 

[FvM]

uln with lcd

The first point is, that you asked for additional ICs without requesting a particular function. I can imagine a lot of. BCD to 7 segment decoder would we one possible function.

As a second point, although possibly sounding penetrant, I like to emphasize the necessity of current limiting resistors for each segment conection, that are missing in the above 4 digit display circuit.

Finally, it's still LED rather than LCD.

 

[thelma]

uln with lcd

pranam do we require any limiting resistors for each segment of the led to burn in case if we use uln???

Added after 2 minutes:

ok FvM,please suggest me one bcd to 7 seg decoder and am pretty confused wether to use limiting resistors or not.
because if am going to use one display resistors are required due to heavy current out that is going to display.but in case if i use 4 display together i don think i would require a resistor.

 

[pranam77]

uln with lcd

Yes..you need to use resistors to every segment connected to the Microcontroller Pins. The value depends on the voltage you use. Using 5volts, 330E may be choosen for good performance and life. Cheers

 

[FvM]

uln with lcd

E.g. CD4543.

If the current limiting is achieved per segment, the segment intensity would vary depending ón the displayed data.

 

[thelma]

pranam as i use 4 disgit display,adding limiting resistors would add complexity to my design.in order to over come this wat can i do??/

 

[pranam77]

All the segments will be connected in parellel inside the 4digit LED display module. Thus only 7 resistors needed to be connecte dto each segment. Thaz all.
Cheers.

 

[thelma]

fine pranam,am completely clear with ur ideas.
now can yu tell me how to go through the data sheets generally.i.e if i use so and so Ic, i can match with other so ans so IC. how should i start as a fresher??

 

[pranam77]

fine pranam,am completely clear with ur ideas.
if i use so and so Ic, i can match with other so ans so IC. how should i start as a fresher??

Sorry..i didnt get your question. Just read...So ans so's......Can you write it in detail?

 

[thelma]

fine for example if i ve few IC's in my hand relevent to some function / application say for example :LED display.
as a starter how should i diagonise this??? this is my question. you may doubt that cant i do if am given a schematic but am talking abt the extreme .as a fresher how wud i start to carry on this operation thou its a meek /tiny thing that 90% of engineers cud do.

 

[thelma]

betwixt,its amazing to read your explanations.i'm also a person who is looking for the same thing wat irshad is doing except the controller because am not yet clear wat setup am asked for.
i would be really thankful if you could suggest based on the below articles which i'm bought to make a led to glow.
1)2 tap transformers
2)4 optocouplers(mct6)
3)CD4053(DIP),74HC14(SOIC)
4)CD4543B
5)ULN2003A

these are the above am asked to use to burn an common anode led 7 seg display.how should i proceed.schematic would be really gud along with the usage of the IC's which am using.please help me.