Looking for a driver for common cathode displays

Thread Starter

k7elp60

Joined Nov 4, 2008
561
I am working on a counter that is using a CD4511 , bcd TO 7 SEGMENT LATCH, DECODER/DRIVER
I would like to use a 7 segment LED display that is common cathode. I am used to using the ULN2004 driver,
but I understand it is for the common anode displays. Is there and driver I can connect between the CD4511
and the common cathode display?
Thanks for looking
Ned
 

jbeng

Joined Sep 10, 2006
72
The CD4511 is actually designed to drive common-cathode LED displays (among others).
See excerpt from its datasheet below...

CD4511 DS pic.jpg
 

dl324

Joined Mar 30, 2015
10,461
You are correct, thanks for the info
You're welcome.

I just realized I didn't describe what I was posting; I hate when people do that.

If you ever needed to drive a common anode display, you could use CD4049 to invert the signals and be able to sink a few milliamps at VCC=5V. For more current, you could use 74AC04 which can sink or source 24mA.
 

jbeng

Joined Sep 10, 2006
72
Or he could use a CD4543 driver which can be easily configured to drive LCDs, common anode/common cathode LEDs or a number of other display types.
I'm surprised that not a lot of people are aware of this chip; I've used them for years.
See the excerpt from the datasheet below.

CD4543 Data Sheet Excerpt.jpg
 

Thread Starter

k7elp60

Joined Nov 4, 2008
561
Does that display have a single LED per segment?
No it has multiple LED's, the typical Vf is 7.2 volts. I forgot to mention in the picture I actually reduced the supply voltage so the LED display would not be so bright. The display is a SunLed # KDMR56C-A.
 

dl324

Joined Mar 30, 2015
10,461
No it has multiple LED's, the typical Vf is 7.2 volts. I forgot to mention in the picture I actually reduced the supply voltage so the LED display would not be so bright. The display is a SunLed # KDMR56C-A.
Thanks for the info.
 
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