The LED is an integral part of the oscillator. As you discovered, the oscillator won't run without it.

Thanks for that input Ron..... is there something I can substitute for the LED.... a regular diode perhaps.... something that won't draw the current of a constantly blinking LED?


Wolf

 

Thanks for that input Ron..... is there something I can substitute for the LED.... a regular diode perhaps.... something that won't draw the current of a constantly blinking LED?


Wolf

The circuit won't oscillate (in simulation) with a silicon diode. You could put two diodes in series, but the average current will be about the same.

You an cut the average current in half (from 3.1mA to 1.4mA) while maintaining the same frequency if you eliminate the jumper between pins 1 and 8, while changing the timing cap to 180uF.
Take the output from pin 2 instead of pin 8, as the waveform is better.
Pin 2 is NOT a good output with your present circuit.

I came up with these conclusions by simulating the circuit. Obviously, I can't guarantee that the hardware results will be the same.

I still recommend a gate oscillator, or a CMOS 555.

 

The circuit won't oscillate (in simulation) with a silicon diode. You could put two diodes in series, but the average current will be about the same.

You an cut the average current in half (from 3.1mA to 1.4mA) while maintaining the same frequency if you eliminate the jumper between pins 1 and 8, while changing the timing cap to 180uF.
Take the output from pin 2 instead of pin 8, as the waveform is better.
Pin 2 is NOT a good output with your present circuit.

I came up with these conclusions by simulating the circuit. Obviously, I can't guarantee that the hardware results will be the same.

I still recommend a gate oscillator, or a CMOS 555.

My head is kinda swimming in all the suggestions I've been getting on this circuit Ron.... and I'd like to find some over lap if it's there.

Is the 74HC132 an example of what you refer to as a gate oscillator, and what Chips referred to as a CMOS inverter?

Back on page 5 of this thread Allen offered a schematic of how he clocked the circuit with a 555, but that timer also has 4 capacitors and 2 resistors attached to make it work..... more board space than I want to surrender if possible.... which is another reason I kept playing with the 3909 and it's lone capacitor.

Wolf

 

As soon as I get some time I will breadboard a 74HC164 and 74HC04 for you.
Too many things happening right now for me.

 

Attached is a simulation of a sequential on/sequential off circuit. The 74HC14 can be replaced by 74HC04, or 74HC132. Ask how to do it if you want to use those parts instead.

 

Thanks Ron. Saves me the trouble.

 

You gentlemen are very kind..... and I do appreciate the time you take to help me with this....

I don't have any of the components you mentioned in the most recent post Ron.... can you point me to a link that ships quick, cheap, and reliable?

When I do go shopping for electronic parts I must admit I really don't know what I'm doing...... don't understand the designation system.... etc.

Tried looking into that attached .asc file..... looks like your typical ascii file in Notepad..... LOL

Wolf

 

BTW Ron..... I might need some other components as well?

I'm looking back at your schematic and I've never seen one quite like this.... so I need to embarrass myself again with some Q's....

It looks like U2 (74HC14) is actually one part, but is "logically" represented as 6, of which 4 are not used?

Is the component labeled V2 (under 74HC.LIB) a symbol to represent a 5V battery?

Are the two capacitors in that same (mini) schematic internal to the IC or something I need to add between pins of HC14 and HC164?

Are the 100nF capacitors the same as my 100uF polarized capacitors?

R2 is a 10meg resistor? Really? How many of those units does a hobbyist need to keep in stock?

Oh well..... I guess I should have expected a funny schematic from you..... cuz you do have a funny hat! :b


Wolf

 

U2 is one component with six inverters built-in. That is why each inverter is labeled U2a to U2f.

V2 is a 5V source. Use whatever 5V source your circuit has available, e.g. output from a voltage regulator or battery to max 6V.

100nF capacitor is the same as 0.1μF, not 100μF.

In any electronics circuit, it is a good idea to put one 0.1μF non-polarized and one 10μF to 100μF polarized (electrolytic) capacitor in parallel with the power supply (Vcc and GND).

10MΩ is common in CMOS circuits. If you are now starting to build up a hobbyist stock, ten is a good number to stock. Resistors are inexpensive, no more than 25 cents for 10.

 

I don't have any of the components you mentioned in the most recent post Ron.... can you point me to a link that ships quick, cheap, and reliable?

You don't say where you are located. Your control panel has a place where you can enter it.

 

Thanks again guys......

(Location updated)

 

Thanks again guys......

(Location updated)

I like Jameco for parts, but there are lots of other good vendors.

 

Ok.... I'm up late this morning (swing schedule) because I forced myself to take the time to do some online shopping... (which I hate doing).

Everything I should need to complete Ron's latest circuit simulation should be here within a week... we'll see what happens.

Between now and then, I'm going to need a "real life" schematic... so I'll submit something like that for your entertainment. (Having pieces of a single IC spread all over a diagram just doesn't seem logical to me.... even if they call them logic symbols.) I think they're idgits.

When I read up on LED's, resistors, transistors, etc...... I could figure out enough to keep me going, but the datasheet on 74HC14 is Martian by comparison! I don't know what a schmit trigger is, or the various gates..... no time to look all that up now.

If someone truly loves me..... they might offer up a BB drawing of how this should look...... :b

BTW.... whilst I was capacitor shopping, I noticed some wares rated as pF. How does pF compare to nF and uF?

Also..... I looked back again..... and your hat isn't really that funny Ron.... kinda cool hat actually...... have you ever jumped out of a plane?


Wolf

 

I will provide a schematic in a short while.
All you need is
one 74HC164
one 74HC04 or 74HC14 or CD4069 hex inverters

 

Here is my circuit:

U2 can be 74HC04, 74HC14 or CD4069.
Adjust R1 and C1 to suit sequence time.
C2 and C3 are power supply decoupling capacitors.

 

Here is my circuit:

U2 can be 74HC04, 74HC14 or CD4069.
Adjust R1 and C1 to suit sequence time.
C2 and C3 are power supply decoupling capacitors.

Your oscillator circuit exceeds the max voltage limits on the input of U2C. Your oscillator will also work with ordinary inverters (non-Schmitt) such as 74HC04, but in either case, you should add a current-limiting resistor (e.g. 100k) in series with the U2C input.

 

The circuit won't oscillate (in simulation) with a silicon diode. You could put two diodes in series, but the average current will be about the same.

You an cut the average current in half (from 3.1mA to 1.4mA) while maintaining the same frequency if you eliminate the jumper between pins 1 and 8, while changing the timing cap to 180uF.
Take the output from pin 2 instead of pin 8, as the waveform is better.
Pin 2 is NOT a good output with your present circuit.

I came up with these conclusions by simulating the circuit. Obviously, I can't guarantee that the hardware results will be the same.

I still recommend a gate oscillator, or a CMOS 555.

Were you contradicting yourself here Ron or did I misunderstand? If pin 2 is not a good output, why suggest using it? Oh well, I was intrigued enough to try it.

I don't have a 180uF on hand, but with 100uF and 220uF capacitors the best I could achieve was (up to) 4 solid LED's. Then I put the jumper back between pin 1 & 8 (with pin 2 still output to 74164 clock) and the circuit behaved as before.

I'll let it run till the batteries are dead to see if it lasts any longer.

Thanks,
Wolf

 

Were you contradicting yourself here Ron or did I misunderstand? If pin 2 is not a good output, why suggest using it? Oh well, I was intrigued enough to try it.

I don't have a 180uF on hand, but with 100uF and 220uF capacitors the best I could achieve was (up to) 4 solid LED's. Then I put the jumper back between pin 1 & 8 (with pin 2 still output to 74164 clock) and the circuit behaved as before.

I'll let it run till the batteries are dead to see if it lasts any longer.

Thanks,
Wolf

What I said was,

Pin 2 is NOT a good output with your present circuit.

Pin 2 IS a good output with the new circuit I posted.

What does this mean?

the best I could achieve was (up to) 4 solid LED's.

4 solid LEDs

I won't comment further on the LM3909. It is an LED flasher. It was never intended to be a clock oscillator. Use one of the other recommended circuits.

 

I'm liking your latest schematic Ron, which utilizes the 74HC14 w/ the 74164 because there are so few components/connections to deal with. While I'm waiting for parts I simulated it in Proteus. I must have got it about right because it is functioning as you described.

It does seem a bit wasteful however to use a 14DIP package when you are only utilizing 6 actual pins. Are there any separate inverters such as these manufactured?

To speed up the simulation, I exchanged the 10M resistor for a 1M, but with actual hardware I expect the frequency will differ.

Also, I omitted the two (C2 & C3) capacitors you have in the separate diagram since I don't see how to put those on a schematic unless I have "real life" representations of the IC's. I'm assuming these capacitors connect across pin 7 and pin 14 of each IC as MrChips had suggested in a previous post?

On a slightly different subject, do you guys know what the differences are between CD4060BE, HEF4060, and HCF4060? I've tried looking this up myself this morning but I'm finding conflicting info. I'd like to know which (if any) are best suited for battery operation (3V - 9V) supply.

Thanks,
Wolf

 

I'm liking your latest schematic Ron, which utilizes the 74HC14 w/ the 74164 because there are so few components/connections to deal with. While I'm waiting for parts I simulated it in Proteus. I must have got it about right because it is functioning as you described.

It does seem a bit wasteful however to use a 14DIP package when you are only utilizing 6 actual pins. Are there any separate inverters such as these manufactured?

To speed up the simulation, I exchanged the 10M resistor for a 1M, but with actual hardware I expect the frequency will differ.

Also, I omitted the two (C2 & C3) capacitors you have in the separate diagram since I don't see how to put those on a schematic unless I have "real life" representations of the IC's. I'm assuming these capacitors connect across pin 7 and pin 14 of each IC as MrChips had suggested in a previous post?

On a slightly different subject, do you guys know what the differences are between CD4060BE, HEF4060, and HCF4060? I've tried looking this up myself this morning but I'm finding conflicting info. I'd like to know which (if any) are best suited for battery operation (3V - 9V) supply.

Thanks,
Wolf

You can get single Schmitt trigger inverters (NC7SZ14) from Mouser and others, but I don't think Jameco has them.
You don't need C2 and C3 in a simulation. They do need to be there (per MrChips) in hardware.
HCF4060 has higher maximum clock speed than CD4060. HEF4060 is even higher. I doubt that you will be wanting to use these parts above 1MHz clock rates. If you do need speed, look up the numbers in the datasheet.
CD4060 has slightly lower output drive capability than the other two.
There may be other subtle performance differences. I believe they are the same logically. None of them are spec'ed below vcc=5V.