LED blinking using 555 and 4040

ericgibbs

Joined Jan 29, 2010
18,766
Hi kuji,
Are saying your circuit does not work.?
If not, what error do you see.?

E

Edit:
You have a join error.
EG57_ 684.png
 
Last edited:

Thread Starter

kuji5

Joined Dec 11, 2022
30
Hi kuji,
Are saying your circuit does not work.?
If not, what error do you see.?

E

Edit:
You have a join error.
View attachment 289607
I suspect that the simulation error is caused by 4040 behaving strangely in Multisim. The error persists even after fixing the bridge. My main question is whether this will work as expected when I turn it into a PCB.
 

LowQCab

Joined Nov 6, 2012
4,026
What do You expect ?
What is the purpose of this Circuit ?
10hz is almost too fast to see.
Most likely the LED will just look kinda dim.
.
.
.
 

Thread Starter

kuji5

Joined Dec 11, 2022
30
What do You expect ?
What is the purpose of this Circuit ?
10hz is almost too fast to see.
Most likely the LED will just look kinda dim.
.
.
.
I don't know. I received this assignment in school and I have to have the finished product ready within 14 days, so I'd rather ask if anyone experienced sees an error in it, so I don't have to search for it laboriously later.
 

Audioguru again

Joined Oct 21, 2019
6,674
The output High of an old 555 is 6.8V when it is powered by 8.2V.
The output high an a CD4040 is only a few volts and only a few mA when loaded with an LED and powered by 6.8V.

Most of your schematics have no Power (pin 16) for the CD4040.
Your first schematic has D1 shorted.

Maybe the simulated model of the CD4040 shows an output at the 6.8V with many amps of current.
 

Alec_t

Joined Sep 17, 2013
14,280
Beware if you or anyone around you suffers from epilepsy! 5Hz-10Hz is the range in which flashing lights can trigger epileptic seizures. You might want to point this out to whoever set your assignment.
 

Thread Starter

kuji5

Joined Dec 11, 2022
30
The output High of an old 555 is 6.8V when it is powered by 8.2V.
The output high an a CD4040 is only a few volts and only a few mA when loaded with an LED and powered by 6.8V.

Most of your schematics have no Power (pin 16) for the CD4040.
Your first schematic has D1 shorted.

Maybe the simulated model of the CD4040 shows an output at the 6.8V with many amps of current.
I also found out that I don't have pins 16 and 8 in my schematic in Multisim, and the bridge has already been fixed. The LED power is a concern, but I will solve it using a transistor as suggested by EricGibbs. Ty
 

Thread Starter

kuji5

Joined Dec 11, 2022
30
Beware if you or anyone around you suffers from epilepsy! 5Hz-10Hz is the range in which flashing lights can trigger epileptic seizures. You might want to point this out to whoever set your assignment.
Yes, he's a bit silly, that's also the reason why I'm asking here and not him.
 

Ya’akov

Joined Jan 27, 2019
9,071
Should this work?
Welcome to AAC.

This thread has been moved to Homework Help since it is a school assignment. In the future please put any schoolwork related threads in Homework Help. AAC rules limit the types of help permitted for schoolwork and so require posting in the correct forum.
 
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