# 7-Segment with CD4511BE BCD Decoder

**URL:** <https://forum.core-electronics.com.au/t/7-segment-with-cd4511be-bcd-decoder/11384>\
**Category:** Support\
**Created:** [15 September 2021 09:18 UTC](https://forum.core-electronics.com.au/t/7-segment-with-cd4511be-bcd-decoder/11384 "2021-09-15T09:18:22Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Dan158392](https://avatars.discourse-cdn.com/v4/letter/d/f17d59/32.png) [@Dan158392](https://forum.core-electronics.com.au/u/Dan158392)\
**Post date:** [15 September 2021 09:18 UTC](https://forum.core-electronics.com.au/t/7-segment-with-cd4511be-bcd-decoder/11384/1 "2021-09-15T09:18:23Z")

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Hi, all  
Some problem with my project:  
Hardware:  
CL5631BW - 3 Digit 7 Segment Display  
[CD4511BE](https://www.apogeeweb.net/circuitry/cd4511be-decoder-driver-datasheet-pinout-parameters-comparison.html) - BCD Decoder

Attachment:  
The BCDA inputs are wired with 680 Ohm Resistor and the outputs are wired with 680 Ohm Resistors to the 7 Segment correctly.  
 ![CD4511BE](https://canada1.discourse-cdn.com/flex028/uploads/core_electronics/original/2X/f/f0f4f99fd5d735efa1d3b28d1f62bf2b4257c9d8.jpeg)

Problem:  
All Numbers shown on the Display are inverted (All segments that should be illuminated are dark and vice versa).  
I think the decoder is for Common Cathodes. Is it possible to change the mode for the decoder to Common Anode? Thank you in advance.

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**Author:** ![Rob110829](https://yyz2.discourse-cdn.com/flex028/user_avatar/forum.core-electronics.com.au/rob110829/32/3151_2.png) [@Rob110829](https://forum.core-electronics.com.au/u/Rob110829)\
**Post date:** [15 September 2021 10:52 UTC](https://forum.core-electronics.com.au/t/7-segment-with-cd4511be-bcd-decoder/11384/2 "2021-09-15T10:52:08Z")

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That decoder is for common cathode, no practical way to change that.

Showing the schematic would help, but also, what’s with the 680R resistors on the inputs?

Is that display really a CC, the only data sheet I can find says it’s CA.

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<div class="post-metadata">

**Author:** ![Dan158392](https://avatars.discourse-cdn.com/v4/letter/d/f17d59/32.png) [@Dan158392](https://forum.core-electronics.com.au/u/Dan158392)\
**Post date:** [14 October 2021 09:35 UTC](https://forum.core-electronics.com.au/t/7-segment-with-cd4511be-bcd-decoder/11384/3 "2021-10-14T09:35:25Z")

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Thank you so much for your response, really appreciate it. I will try to get one fully assembled display module for my project. 🤔