

A CD4067, HC or HCT4067 version Analog Multiplexer would do if you keep the current down on the LED's. They have an Inhibit pin!Here's a 32 LED version:
View attachment 323221
I don't know of a commercial 4:16 encoder with enable.
That decoder has not been made for many years now. So the solution is to use two 3:8 decoders and put the fourth bit to the enable line inverted to one of them.Here's a 32 LED version:
View attachment 323221
I don't know of a commercial 4:16 encoder with enable.
My bad. CD4514/5 do have an inhibit (and a latch).A CD4067, HC or HCT4067 version Analog Multiplexer would do if you keep the current down on the LED's. They have an Inhibit pin!
+Here's a 16 LED circuit using a binary counter and a 4to16 encoder:
I believe there is the problem. It is a DE-coder, is decoding the input binary into Decimal.I don't know of a commercial 4:16 encoder with enable.
I looked into my ICs and I only have 1 model this CD4514 = 4 to16 line decoder/demultiplexerI breadboarded this in the 70's, but I don't have a schematic or the breadboard available at the moment.

The encoder can be CD4514 (or CD4515 for the opposite polarity).
CD4516 is a binary counter and is a correct encoder for the cct.Interesting! I never seen one. I will give it a try in my sim someday.You can make it more interesting by using a binary rate multiplier (CD4089) to change the frequency so the dot moves faster for the center counts.


The definition of encoder and decoder never made sense to me and I use them pretty much interchangeably.But your CD4514 or CD4515 are not encoders. They are decoders.
What isn't readable in the images that I posted? That's what I get when I use the snap shot tool and paste the image into the browser. I'll see if saving as an image file first makes a difference. (EDIT: makes no difference.)I made a Better Rez img of your cct and with --Proper Notations--.
The decoder/encoder I used was a component I made and it doesn't have any commercial equivalent. I don't add component designators because I'd have to do that manually. I started adding pin numbers to new components, but don't have much interest in modifying components I've already created.And always put all IC names in your ccts. As a general rule for yourself later and for others. It is my gen rule so Im teaching my experience to you.
Set/preset and reset/clear are synonyms. I use them interchangeably.I also put MY FF 7473 + its correct notations S=Set and R=Reset. It must
What isn't clear?I definetly not sure of the wiring for your second version, the cascaded LED_Scanner_cct with 32 Leds.
The simulator I use connects any unconnected inputs to ground. I should have mentioned that or connected them explicitly for those who don't know that inputs shouldn't be left unconnected.I notice your 2nd FF D and CLK pins were floating.... they are inputs, and they should definetly be linked to GND (like in your 16_Leds version)
I understand that you wanted to use CD4017, but an up/down counter is more appropriate. once you got past 5 LEDs.The original idea was to play with the 4017 (which I like it very much for its simplicity) and squeeze all it can got.
Your idea is not bad for a Scanner LED cct !!! I like it.
I assume you meant 7474. Preset and clear are high active on my symbols so you need inverters on the flip flop that changes count direction.Specifically for my FF 7473 that I have, I must tie to + rail its S and R pins, so I modified your cct from this pov. (We will know better after simulation)

You assume wrong. I have both of them and I specifically choose 7473 because is a J-K FF and is in acordance to your cct, while 7474 is a DTFF and is not in accordance to what you have used there. Thats my reasoning. I was folowing your cct but with the ICs I have.I assume you meant 7474.
I misspell, I meant "your" cct that I rebuild it with my components and the wiring in what I made. Hope is right.What isn't clear?
explain in more detail, I want to see what you see. For me they are VERY distinctive but maybe Im a noob at them compared to you.The definition of encoder and decoder never made sense to me and I use them pretty much interchangeably.
Find a way to make it bigger size as a file alone and then post it in the forum thread. Trust me, its better at bigger rez and you will get used to it in time. You should trust my word; im a profesional artist afterall, with absolutly no money for 11years.I'll see if saving as an image file first makes a difference. (EDIT: makes no difference.)
always connected them explicitly !I should have mentioned that or connected them explicitly for those who don't know
Hmmm, its not new to me and I have seen these (and others) notations but I stopped at Set and Reset. For me it has more sense and more easy to remember and to visualize in my mind. I suppose its a matter of "getting used" to a certain mentality in the end. For me preset and clear does not click - at all ! Haha.TI uses preset and clear
Sorry, but that won't work.To make a 20 LED chaser using a 4017 decade counter, connect the clock input of the 4017 to a 555 timer configured as an astable oscillator to provide a continuous pulse signal. The 4017 has 10 outputs, so to control 20 LEDs, you'll need two 4017 ICs. Connect the carry-out pin (pin 12) of the first 4017 to the clock input (pin 14) of the second 4017. Connect the LEDs to the output pins of both 4017 ICs, with the cathodes to ground through current-limiting resistors. Ensure to reset the second 4017 at count 10. This way, as the clock pulses, the LEDs will light up one by one in sequence from 0 to 19, with only one LED on at a time.
I used a D flip flop.You assume wrong. I have both of them and I specifically choose 7473 because is a J-K FF and is in acordance to your cct, while 7474 is a DTFF and is not in accordance to what you have used there. Thats my reasoning. I was folowing your cct but with the ICs I have.
Manufacturers are going to label pin functions the way they want to, and you need to be able to adapt.For me preset and clear does not click - at all ! Haha.
This is how I interpret it originally, when I first see it.I used a D flip flop.


what is the name of the simulation bro ? I want to try some circuit online so i can wired it in a breadboard or PCBI agree they are plenty... but not what I want.
If you mean this cct version:
View attachment 321000View attachment 321003
This type of cct is good as a clock.
Well, When A is clocking B is not doing it sequentially, meaning 1 after 1 (or one after another), but binary, meaning when A is finishing a pass, it will increment B with 1 and then A will start another round.
It is counting 0123456789 in A then 11 in B. (since 10 was lit up until this time) then again 0123456789 in A then 12 in B (since 11 was lit up until this time) and so on.
All I want is an incremental and cursive 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
While using it, we still attached the 16th and 8th Pin into the VCC and GND for the two ICs to work, right?I agree they are plenty... but not what I want.
If you mean this cct version:
View attachment 321000View attachment 321003
This type of cct is good as a clock.
Well, When A is clocking B is not doing it sequentially, meaning 1 after 1 (or one after another), but binary, meaning when A is finishing a pass, it will increment B with 1 and then A will start another round.
It is counting 0123456789 in A then 11 in B. (since 10 was lit up until this time) then again 0123456789 in A then 12 in B (since 11 was lit up until this time) and so on.
All I want is an incremental and cursive 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
He's using Proteus. It isn't a free simulator. I'm using DigitalWorks which is, but it doesn't have any useful commercial parts. You have to make your own.what is the name of the simulation bro ? I want to try some circuit online so i can wired it in a breadboard or PCB
Not all logic simulators and schematic editors show explicit power and ground connections.While using it, we still attached the 16th and 8th Pin into the VCC and GND for the two ICs to work, right?

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