interfacing 7segment 4-digit LED's

[anurag2700]

7-segment 4 digit led

please help me in how to interface 9 seven segment 4-digit LED's by using PSoc or microcontroller such that i use multiplexed display.

 

[sau_sol]

mcs51 7segment 4digit

you want to interface 9 seven segment displays
which are having 4 led's each?????:?::?::?::?::?:
Please more clarify
which controller???

 

[anurag2700]

4 digit led display

i.e seven segment 4-digit common anode displays.i m also in dilemma which to use
PSoc or microcontroller(8051 or PIC).

 

[sau_sol]

7seg 4digit

what is your application ?
because this type of display can be controlled by any simple controller
but it also depends on other application you are doing with the controller.

if you required inbuilt ADC go for avr or pic
but for digital only you can do it using 8051 only

 

[anurag2700]

conect leds to psoc

My project is that when a person stands on a pressure sensor we should note down this value as weight on Earth by calibrating.I have to display the weights on all planets using 9 different seven segment 4-digit LED's such that all can be seen at a time to human.

 

[sau_sol]

seven segment interface 4 digit 8051

thats a good project and the display interface can be made using a microcontroller

but which pressure sensor you are using?

for the display you have to connect the common anode of the displays to different pins with a transistor to be able to enable or disable one at a time
and continuously feed the data onto the display

you can also use a 20x4 alphanumeric LCD display to show 9 parallel weights

 

[anurag2700]

4digit 7 segment anzeige

I want to use MPX4250D Pressure Sensor - (0 to 250 kPa).It generates an Analog output.
Cant we do this easily with PSoc??
I have to display all of them seperately..with 1feet space between them on the wall.

Added after 2 minutes:

while doing with PSoc designer-5 i m facing current problem.

 

[sau_sol]

7seg 12 pin 4 dig

for this you will be needing a PSoC with a good ADC
and also you can use buffer IC for storage of the display of the 7 segments
otherwise you have to refresh them at a very raid rate to display them correctly

 

[anithatg]

interfacing mp with 7 segment display

I think the following Application notecan help you

https://www.cypress.com/?rID=2609

Regards,
Anitha

 

[AhmadAbuOmar]

8051+led interfacing+multiplexing

hi,

u can simply use pic16f877a for this project

the prussure sensor output is to be fed to RA0 or any pin of porta. then u enable the A/D converter and convert the analogue signal to digital one. and divide or multiply with the apropriate factor inside the code.

after this u send it to 7sig display using portb.

the problem is how to connect the 9 units and how to send data

i think i need to see the datasheet of the 4digits 7sig display and see how the connections are made.

gl

 

[anurag2700]

yeah....thank u very much.....
we r thinking of using multiplexed display for 9 Led's

 

[doraemon]

Hello!

Just a silly question. I am aware there may be a good reason to use 9 4-digit
LEDs, but just in case:
Wouldn't it be simpler and more economical to use an LCD? In this case, you
could write all the values on the same panel. No multiplexing needed.

Dora.

yeah....thank u very much.....
we r thinking of using multiplexed display for 9 Led's

 

[mike.11]

Re: 7-segment 4 digit led

**broken link removed**
this link might be useful

 

[cent24.3]

Waow,

9 displays of 4 digits 7seg leds.
So you are expecting to drive 9 x 4 x 7 = 252 leds !
If I'm right, and if this was independent leds , you'll need at least 12 three states I/O able to drive a led directly (with only a limiting resistor) to achieve this (with 12 three states I/O you can drive 2 x 11 x 12 = 264 leds, and you'll even have 12 more leds to drive if needed).
But with 7 seg digit it's little bit hard to guess the number of I/O, and you have to mix common anode and common cathode to minimise the number of I/O needed. I think you'll need 16 three states I/O to drive up to 60 digits (30 common cathode and 30 common anode)
Programming the pic will be quite tricky, the simple way is to drive one led at a time (to have the same light intensity for each led) and going very fast through all the leds.
The maximum current source and sink by the pic is 25mA, time sharing this current for all the leds : for 252 leds it's 0.1mA for each leds (you have to take hi efficiency 7seg).

An other solution is to take 9 small pic (like 16f84) just to drive each 4 digits block and send the text to display via serial lines. The wiring will be lot simple too.

Hope that will help !

 

[akoangsimula]

hi can u help me with 4x3 keypad interfacing in zilog?
thanks!!