Hi Dennis:

I have now tried the circuit and it doesn't work. I have tested the clock portion of the circuit and it works. I tested the CD4511BE and the
Display prior to building the circuit and they work. I am wondering about the inputs.

M

It is so easy for one to say "it doesn't work" because for the end user that is all they care about.
There is always the opportunity to give more information in order to assist in trouble shooting.

For example, one could add:
"The display shows a constant 0 (or whatever) but does not advance even though I have given the counter a valid input clock pulse".

 

Hi:
I tried that but it doesn't like that.
M

How do you know "it doesn't like that"?
Does it make a quick dash to the toilet?

Read my previous post.

 

How do you know "it doesn't like that"?
Does it make a quick dash to the toilet?

Read my previous post.

HI:
Ya it almost knocked me over making the dash. LOL. All segments are lit up.
The lamp test pin 3 is grounded. If I remove the ground connection for
pin 3, none of the segments light.
M

 

HI:
Ya it almost knocked me over making the dash. LOL. All segments are lit up.
The lamp test pin 3 is grounded. If I remove the ground connection for
pin 3, none of the segments light.
M

Ah, that's better.
Remove the ground connection to pin-3.
Connect pin-3 and pin-4 to +5V.
Connect pin-5 to GND.
Put 1k-10kΩ pull-down resistors on pins 1, 2, 6, 7.
The display should show "0".

 

Ah, that's better.
Remove the ground connection to pin-3.
Connect pin-3 and pin-4 to +5V.
Connect pin-5 to GND.
Put 1k-10kΩ pull-down resistors on pins 1, 2, 6, 7.
The display should show "0".

View attachment 314516

When I mentioned pin 3 being grounded, I meant on the CD4511BE,
not the counter. Should it still be grounded?

 

When I mentioned pin 3 being grounded, I meant on the CD4511BE,
not the counter. Should it still be grounded?

The circuit diagram below shows CD4511.
Pin-3 and pin-4 of CD4511 must be connected to +5V.
Pin-5 must be connected to GND.

 

The circuit diagram below shows CD4511.
Pin-3 and pin-4 of CD4511 must be connected to +5V.
Pin-5 must be connected to GND.

View attachment 314518

Hi:
I don't understand. Aren't pins 1,2,6 and 7 inputs from the counter.
I have them connected to the CD4510 outputs. If I install pull-downs
it will short out the CD4510. I must be missing something.

 

Hi:
I don't understand. Aren't pins 1,2,6 and 7 inputs from the counter.
I have them connected to the CD4510 outputs. If I install pull-downs
it will short out the CD4510. I must be missing something.

Disconnect the CD4510 for now. We are testing the CD4511 only.
If you connect 1k-10kΩ pull-down resistors, you are inputting zero. We ought to see "0" on the display
After doing that, connect pin-7 to +5V. We ought to see "1" on the display.
(You can leave the pull-down resistors in place. They would not hurt anything.)

 

Disconnect the CD4510 for now. We are testing the CD4511 only.
If you connect 1k-10kΩ pull-down resistors, you are inputting zero. We ought to see "0" on the display
After doing that, connect pin-7 to +5V. We ought to see "1" on the display.
(You can leave the pull-down resistors in place. They would not hurt anything.)

OK. "0" test and the "1" test worked. My next step will be to get this beast counting.

 

OK. "0" test and the "1" test worked. My next step will be to get this beast counting.

Now remove the pull-down resistors and reconnect the CD4510.

 

Now remove the pull-down resistors and reconnect the CD4510.

Did that. The display shows the number "4" and does not count.

 

Connect pins 1, 5, 9 and 10 of the CD4510 to GND.
It should be counting DOWN on each clock pulse.

 

Connect pins 1, 5, 9 and 10 of the CD4510 to GND.
It should be counting DOWN on each clock pulse.

View attachment 314528

View attachment 314529

Did that. It now displays a "6" and doesn't count.

 

Did that. It now displays a "6" and doesn't count.

It is now counting down. The problem was that I had a single LED
on the clock output so that I could see that the clock was working.
That must have killed the signal going to the CD4510?

The funny thing is, if I power down and back up, the count starts at weird values, not
"0".

 

It is now counting down. The problem was that I had a single LED
on the clock output so that I could see that the clock was working.
That must have killed the signal going to the CD4510?

The funny thing is, if I power down and back up, the count starts at weird values, not
"0".

All newcomer mistakes.

1) When you power up, the counter will start at any random state. We can fix that later.
2) Never connect LEDs directly to logic signals. Always use an inverter or buffer to drive the LED. Never assume that the signal that drives the LED is a valid logic voltage. In other words, don't take that signal to drive another logic circuit.

Now, remove the GND at pin-10 of the CD4510.
Connect pin-10 to +5V and watch the counter count UP.

 

All newcomer mistakes.

1) When you power up, the counter will start at any random state. We can fix that later.
2) Never connect LEDs directly to logic signals. Always use an inverter or buffer to drive the LED. Never assume that the signal that drives the LED is a valid logic voltage. In other words, don't take that signal to drive another logic circuit.

Now, remove the GND at pin-10 of the CD4510.
Connect pin-10 to +5V and watch the counter count UP.

Thanks for the inverter/buffer advice. I will put that in my notes.
The circuit now counts up.
M

 

The problem was that I had a single LED
on the clock output so that I could see that the clock was working.
That must have killed the signal going to the CD4510?

You don't mention what is generating the clock or what the forward voltage of the LED is.

If you take the time to read the datasheets, they'll give you the information you need.

From the TI datasheet:


The counter increments on the rising edge of the clock. With a 5V supply, a high level input voltage must be at least 3.5V.

If you were using a red, green, or yellow LED, the forward voltage is probably less than 3.5V.

Input signals greater than 1.5V but less than 3.5V will give unpredictable results.

 

Now, about that POWER-ON RESET (POR) circuit.
You can get fancy or you can go simple

Firstly, you need to know if it takes a logic HIGH or logic LOW signal to RESET.
Read the device datasheet.

CD4510 datasheet

CD4510 requires high voltage to RESET.
So we want a high voltage that falls to low voltage after a short delay.

Here is your simple logic HIGH reset.
Try,
R = 100kΩ
C= 0.1μF to 1μF
Add a diode to speed up the discharge of the capacitor on POWER DOWN.

 

Also, it's bad practice to leave the Presetting pins 3,4,12 & 13 open circuit when unused. For now, tie them either high or low.

 

Now, about that POWER-ON RESET (POR) circuit.
You can get fancy or you can go simple

Firstly, you need to know if it takes a logic HIGH or logic LOW signal to RESET.
Read the device datasheet.

CD4510 datasheet

CD4510 requires high voltage to RESET.
So we want a high voltage that falls to low voltage after a short delay.

Here is your simple logic HIGH reset.
Try,
R = 100kΩ
C= 0.1μF to 1μF
Add a diode to speed up the discharge of the capacitor on POWER DOWN.

View attachment 314548

Thanks!