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how? momentary switch light up leds in order?

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I think one resistor might work but with the rotary switch I think it adds a problem
I followed this circuit
look at last circuit in particular. why reinvent the wheel?
basically same circuit but added rotary switch.

That's one of the circuits that I was referring to. There is no need for 10 dropping resistors. Only one output at a time is high, driving that LED through a resistor. If all the cathodes are connected to one resistor, the one conducting LED will pull the resistor high, reverse biasing the 9 other LEDs on the low outputs. Attaching the reset pin through the switch to the outputs/LED-anodes would not be a problem.

Ken
 
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MrBED,
About your circuit:
1. With a 270Ω LED-resistors and a 9V supply you are going to pull 27mA from the outputs...that are only rated at ~3.5mA on a CD4017.
The datasheet from Texas Instruments shows that a CD4017 with a 10V supply has an output current of 9.5mA to 19.5mA into a dead short or 8mA to 16mA into a 3.5V blue or white LED without any current-limiting resistor.
Each output transistor will dissipate double its allowed amount into a short circuit and will dissipate an allowed amount into an LED.
With a 9V supply the currents are a little less.
If the 9V battery voltage drops to 6V then the currents are just a couple of mA.

2. And I've seen this in several versions, since only one LED will be ON at a time, you only need one LED current limiting resistor. Tie all the LED cathodes together and to one resistor, that goes to ground.
But then each LED will have a reverse voltage that is higher than the max allowed reverse voltage of only 5V.

You don't need any current-limiting resistors when the supply voltage is only 9V.
 
Thanks. Was thinking 5V supply.

Ken
 
I wish I had taken an electronics class cause I really do enjoy this stuff but some of it is just a bit over my head.

Neil
 
I took a class in H. S.

this was in the late 60's and the teacher was into tubes.
then again I was/am lousy in math.
I enjoy digital electronics.
my "bible" is Forest Mims circuit book from radio Shack.
have two different issues.
another is the TTL cookbook
Wish I could aford a full version of an electronics simulation program.
I have the free version of TINA but latly been losing faith in it as it seems to output the wrong data?? of coarse it could be my wrong input data
A computer is only as smart or good as the data input into it.
 
I got rid of my TTL Cookbook in about 1975 when I started using Cmos and got the Cmos Cookbook.
 
The old TTL Cookbook had many old circuits.
TTL needed a 5V regulator and used a lot of supply current.
Cmos operates from 3V to 18V without a regulator and its supply current is almost zero if its switching frequency is low.
The Cmos Cookbook has many new circuits.
 
updated pokertable LEDs

just for the heck of it (might learn something) I drew out the poker leds using several cmos ic's
The dealer rotates the BCD switch for # of players then as play progresses the dealer or the players (have 10 NO switches) presses the button and the leds light up in progression.
the 4017 recycles when the output of the 4518 = the BCD
I might just have to build a table and include the progressive LED feature.
sell it on Ebay!!
maybe there's a market--???
That's what Bill Gates said--lol
 

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that schematic just went way above my head hahaha. I appreciate the work man! So you are using 10 normally open switches? We were hoping to get away with one pushbutton or switch which the dealer controlled. The players do not want to have to mess with remembering to hit a button when the chip is moved. I can not tell you how much I appreciate you all helping me out though. I am very new to reading schematics so that last schematic looks a bit overwhelming but I will dig a little deeper into it.

I see that one of the components you used says coded. I deffinately do not have anything to write code to chips with.

Neil
 
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neilyboy,

The "coded" component is just a switch with 10 positions and outputs 4 lines that are high or low based on a Binary-Coded-Decimal (BCD). The coding is in the hardware...no programming.

But, are you looking for something other than the circuit I posted earlier? https://www.electro-tech-online.com/threads/how-momentary-switch-light-up-leds-in-order.88850/#post696093

It doesn't even need the Dealer Reset button. Just drop R2, C2, and that button and ground pin 15. Drop the supply voltage to 5V and you get around Audioguru's concern of dealing the LED's reverse bias voltage, with one dropping resistor. It doesn't get much more simple. And meets you minimal spec...one button...10 LEDs...one LED at a time... move one position with each button push...minimum component count.

ken
 
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Now I feel like I was being pushy...but was just curious if there something we were missing.

Ken
 
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no nothing missing other than my lack of knowledge haha. I appreciate all the work.. I am just trying to simplify it for myself and hope that it works... I will order up the parts this week from digikey and hopefully have something put together and working later on. Thanks again for all the effort it is very much appreciated!


Neil
 
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