ic 555 timer small diagram needed

right what i need is a diagram for the conditions i need... let me
explain

i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation

many thanks
Ian

ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?
 
B

bw

Jan 1, 1970
0
right what i need is a diagram for the conditions i need... let me
explain

i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation

many thanks
Ian

ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?

A CMOS 556 would work, but since you don't need to know how it works, just
purchase a timer at the store.
Another idea is to scavenge a microwave oven control board, save the keypad.
I've done it and it will do what you want.
 
E

ehsjr

Jan 1, 1970
0
right what i need is a diagram for the conditions i need... let me
explain

i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation

many thanks
Ian

ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?

Getting 15 minutes from a 555 reliably is tough. Instead,
set the 555 to run astable at ~2.5 minutes, and use its
output as the clock for a 4017.

Diode or all of the 4017 outputs except count 9 to the base
of an NPN and a 1K. An example of the "diode or" is best seen
in the second partial schematic below. The schematics are
representative of what you need to do, not complete. The N/O
switch also connects to the commoned cathodes of the diodes.
The NPN controls power to the circuit. Pressing the button
turns the NPN on, and the 4017 keeps it turned on until the
count reaches 9, in ~ 20 minutes. Diode or counts 7 and 8
to another NPN through a 1K - that transistor can control a
relay to give you you a ~ 5 minute output.

NPN
+12 ---+---+ +------- Vcc to 555 and 4017 and relay
| c\ /e
| ---
| |
| [1K]
| | Dx
+-o o-+------|<---Counts 0-8 from 4017,
N/O | each count thru its own
| diode (Dx)
[33K]
|
Gnd ---------+

The 33K ensures the transistor turns off when the 4017
is not counting from 0 through 8.

For your 5 minute output:

+Vcc ----+
|
[Relay]
| +---|<---Count 8 from 4017
\c |
NPN |---[1K]---+---|<---Count 7 from 4017
/e |
| |
Gnd -----+----[33K]---+

The relay needs a diode across it with the cathode
connected on the + side.

Ed
 
A CMOS 556 would work, but since you don't need to know how it works, just
purchase a timer at the store.
Another idea is to scavenge a microwave oven control board, save the keypad.
I've done it and it will do what you want.

i dont have any decent gadget shops that do what i need..

i need from a push button 15mins off then 5 min on then off waiting
for push button again to start again at 115 off etc etc, the microwave
controll would allow it to be on for 15 mins and off permenant,, not
what i need
 
B

Bo Vance

Jan 1, 1970
0
right what i need is a diagram for the conditions i need... let me
explain

i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation

many thanks
Ian

ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?

Maybe this would help.
<http://ourworld.compuserve.com/homepages/Bill_Bowden/page9.htm#555delay.gif>
 

neon

Oct 21, 2006
1,325
Joined
Oct 21, 2006
Messages
1,325
that is easy done use pin 2 to trigger the first timer then use the ouput to trigger the next and so forth. use the lm555 as monostable once triggered it will time out for the time you set you can reset it at any time using pin 4. and to get long times like hours use a current source as apposed to plain resistors.
 
right what i need is a diagram for the conditions i need... let me
explain
i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation
many thanks
Ian
ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?

Getting 15 minutes from a 555 reliably is tough. Instead,
set the 555 to run astable at ~2.5 minutes, and use its
output as the clock for a 4017.

Diode or all of the 4017 outputs except count 9 to the base
of an NPN and a 1K. An example of the "diode or" is best seen
in the second partial schematic below. The schematics are
representative of what you need to do, not complete. The N/O
switch also connects to the commoned cathodes of the diodes.
The NPN controls power to the circuit. Pressing the button
turns the NPN on, and the 4017 keeps it turned on until the
count reaches 9, in ~ 20 minutes. Diode or counts 7 and 8
to another NPN through a 1K - that transistor can control a
relay to give you you a ~ 5 minute output.

NPN
+12 ---+---+ +------- Vcc to 555 and 4017 and relay
| c\ /e
| ---
| |
| [1K]
| | Dx
+-o o-+------|<---Counts 0-8 from 4017,
N/O | each count thru its own
| diode (Dx)
[33K]
|
Gnd ---------+

The 33K ensures the transistor turns off when the 4017
is not counting from 0 through 8.

For your 5 minute output:

+Vcc ----+
|
[Relay]
| +---|<---Count 8 from 4017
\c |
NPN |---[1K]---+---|<---Count 7 from 4017
/e |
| |
Gnd -----+----[33K]---+

The relay needs a diode across it with the cathode
connected on the + side.

Ed

Right, so basically I connect to the npn transistor by diodes (or
leds?) with pins 1, 2, 3, 4, 7 and 10 and use pins 5and 6 connected to
the npn and opto-isolation device instead for switching another npn
for a relay. It’s the same as a diode but using less power than the
relay, so I figured that out its now the 555 timer connection and
circuit to the cmos chip.

The tech sheet I was looking at started from output 0, this means
pins 9 and 11 don’t use (just incase someone else finds this useful)

right the 555 pinout?
1,is gnd
2, E from npn
3, connect to hi-low on cmos
4,dont use
5,dont use
6, connect to ground?
7, connect c+r to 1
8, V+

please can you confirm I have this correct

Questions.
What do the diodes and the switch connect to on the npn, I really need
a better drawing.
I did see on the tech sheet of the cmos chip it sounds like that the
output pins give out different power or something as it suggests that
only certain pins to be used to time another decade counter cmos chip,
is this right if so do I still use diode to the npn?
 
E

ehsjr

Jan 1, 1970
0
right what i need is a diagram for the conditions i need... let me
explain
i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation
many thanks
Ian
ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?

Getting 15 minutes from a 555 reliably is tough. Instead,
set the 555 to run astable at ~2.5 minutes, and use its
output as the clock for a 4017.

Diode or all of the 4017 outputs except count 9 to the base
of an NPN and a 1K. An example of the "diode or" is best seen
in the second partial schematic below. The schematics are
representative of what you need to do, not complete. The N/O
switch also connects to the commoned cathodes of the diodes.
The NPN controls power to the circuit. Pressing the button
turns the NPN on, and the 4017 keeps it turned on until the
count reaches 9, in ~ 20 minutes. Diode or counts 7 and 8
to another NPN through a 1K - that transistor can control a
relay to give you you a ~ 5 minute output.

NPN
+12 ---+---+ +------- Vcc to 555 and 4017 and relay
| c\ /e
| ---
| |
| [1K]
| | Dx
+-o o-+------|<---Counts 0-8 from 4017,
N/O | each count thru its own
| diode (Dx)
[33K]
|
Gnd ---------+

The 33K ensures the transistor turns off when the 4017
is not counting from 0 through 8.

For your 5 minute output:

+Vcc ----+
|
[Relay]
| +---|<---Count 8 from 4017
\c |
NPN |---[1K]---+---|<---Count 7 from 4017
/e |
| |
Gnd -----+----[33K]---+

The relay needs a diode across it with the cathode
connected on the + side.

Ed


Right, so basically I connect to the npn transistor by diodes (or
leds?) with pins 1, 2, 3, 4, 7 and 10

Yes those are the correct pins, but you need to add
more pins - pin 9 and pin 10. That will give you
counts 0,1,2,3,4,5,6,7, and 8. Each count stays
active for 2.5 seconds, so the timing cycle is
2.5 * 8 = 20 seconds. Each output (count) goes +
for 2.5 seconds. The output is connected through
a diode, and the cathodes of t6he diodes are connected
together. The base of the NPN is connected to the cathodes
through a 1K resistor.

The collector of that NPN is connected to the plus
side of whatever power supply you are using. The power
supply needs to be between 5 and 15 volts. The emitter
of that NPN provides power for the 4017, the 555 and the
relay.
and use pins 5and 6 connected to

No, use pins 6 and 9. They are connected to 2 more diodes.
Those two diodes als have their cathodes connected to a 1K
resistor, and the other side of that 1K resistor is connected
to the base of another NPN transistor. No opto isolator is
needed or used.
the npn and opto-isolation device instead for switching another npn
for a relay. It’s the same as a diode but using less power than the
relay, so I figured that out its now the 555 timer connection and
circuit to the cmos chip.

The tech sheet I was looking at started from output 0, this means
pins 9 and 11 don’t use (just incase someone else finds this useful)

You will use pin 9, but you won't use pin 11
right the 555 pinout?
1,is gnd
2, E from npn
3, connect to hi-low on cmos
4,dont use
5,dont use
6, connect to ground?
7, connect c+r to 1
8, V+

please can you confirm I have this correct

No - see below.
Questions.
What do the diodes and the switch connect to on the npn,

The base of the NPN, through a 1K resistor.
I really need
a better drawing.
I did see on the tech sheet of the cmos chip it sounds like that the
output pins give out different power or something as it suggests that
only certain pins to be used to time another decade counter cmos chip,
is this right if so do I still use diode to the npn?

For a diagram of the 555, see this url:
http://www.doctronics.co.uk/555.htm#astable

You will select R1, R2 and C to set the timing for
~ 2.5 seconds. Start with R1 = 33K and use a 50K
pot for R2. For C, use a 33 uF electrolytic.
You can adjust the pot to "fine tune" the 2.5
second pulses that the 555 will produce.

You can also find a diagram of the 4017 at
http://www.doctronics.co.uk/4017.htm

Connect the output (pin 3) of the 555 to the clock input
of the 4017 through a 1K resistor.

If this is not clear, I can email a jpg schematic
to you.

Ed
 
E

ehsjr

Jan 1, 1970
0
ehsjr said:
[email protected] wrote:

right what i need is a diagram for the conditions i need... let me
explain


i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation


many thanks
Ian


ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?


Getting 15 minutes from a 555 reliably is tough. Instead,
set the 555 to run astable at ~2.5 minutes, and use its
output as the clock for a 4017.

Diode or all of the 4017 outputs except count 9 to the base
of an NPN and a 1K. An example of the "diode or" is best seen
in the second partial schematic below. The schematics are
representative of what you need to do, not complete. The N/O
switch also connects to the commoned cathodes of the diodes.
The NPN controls power to the circuit. Pressing the button
turns the NPN on, and the 4017 keeps it turned on until the
count reaches 9, in ~ 20 minutes. Diode or counts 7 and 8
to another NPN through a 1K - that transistor can control a
relay to give you you a ~ 5 minute output.

NPN
+12 ---+---+ +------- Vcc to 555 and 4017 and relay
| c\ /e
| ---
| |
| [1K]
| | Dx
+-o o-+------|<---Counts 0-8 from 4017,
N/O | each count thru its own
| diode (Dx)
[33K]
|
Gnd ---------+

The 33K ensures the transistor turns off when the 4017
is not counting from 0 through 8.

For your 5 minute output:

+Vcc ----+
|
[Relay]
| +---|<---Count 8 from 4017
\c |
NPN |---[1K]---+---|<---Count 7 from 4017
/e |
| |
Gnd -----+----[33K]---+

The relay needs a diode across it with the cathode
connected on the + side.

Ed



Right, so basically I connect to the npn transistor by diodes (or
leds?) with pins 1, 2, 3, 4, 7 and 10


Yes those are the correct pins, but you need to add
more pins - pin 9 and pin 10. That will give you
counts 0,1,2,3,4,5,6,7, and 8. Each count stays
active for 2.5 seconds, so the timing cycle is
2.5 * 8 = 20 seconds. Each output (count) goes +
for 2.5 seconds. The output is connected through
a diode, and the cathodes of t6he diodes are connected
together. The base of the NPN is connected to the cathodes
through a 1K resistor.

Groan - you wanted 2.5 minutes, not seconds. Change the
word seconds to minutes above. Correction to the 555
components appears below. Also, I added 1 pin too
many. You want counts 0,1,2,3,4,5,6 and 7, so you need
to add pin 10 (not pins 9 and 10 - do not add pin 9).
The collector of that NPN is connected to the plus
side of whatever power supply you are using. The power
supply needs to be between 5 and 15 volts. The emitter
of that NPN provides power for the 4017, the 555 and the
relay.



No, use pins 6 and 9.
^^^ ^^ ^^
Yes, use pins 5 and 6
They are connected to 2 more diodes.
Those two diodes als have their cathodes connected to a 1K
resistor, and the other side of that 1K resistor is connected
to the base of another NPN transistor. No opto isolator is
needed or used.



You will use pin 9, but you won't use pin 11



No - see below.



The base of the NPN, through a 1K resistor.


For a diagram of the 555, see this url:
http://www.doctronics.co.uk/555.htm#astable

You will select R1, R2 and C to set the timing for
~ 2.5 seconds. Start with R1 = 33K and use a 50K
pot for R2. For C, use a 33 uF electrolytic.
You can adjust the pot to "fine tune" the 2.5
second pulses that the 555 will produce.

Aaargh! I figured the timing components for the 555
based on seconds, not minutes. Change R1 to 330K,
R2 to a 500K pot, and C to a 220 uf cap to get 2.5
_minute_ timing.

Ed
 
ehsjr said:
[email protected] wrote:
[email protected] wrote:
right what i need is a diagram for the conditions i need... let me
explain
i need to press and release a NO switch and after certain time like
say 15 mins i need it to engage a relay for say 5 mins then disengage
the relay and wait for the push button again after.
**i could go as far as opto-isolation as it doesnt need much current
for switching but it does need seperation
many thanks
Ian
ps i seen many diagrams with this tan and other but there talking
beyond what need to know.. i got a strong guess i need 2x555 and
perhaps what they call a "flip flop" circuit unless anyone has a
better idea?
Getting 15 minutes from a 555 reliably is tough. Instead,
set the 555 to run astable at ~2.5 minutes, and use its
output as the clock for a 4017.
Diode or all of the 4017 outputs except count 9 to the base
of an NPN and a 1K. An example of the "diode or" is best seen
in the second partial schematic below. The schematics are
representative of what you need to do, not complete. The N/O
switch also connects to the commoned cathodes of the diodes.
The NPN controls power to the circuit. Pressing the button
turns the NPN on, and the 4017 keeps it turned on until the
count reaches 9, in ~ 20 minutes. Diode or counts 7 and 8
to another NPN through a 1K - that transistor can control a
relay to give you you a ~ 5 minute output.
NPN
+12 ---+---+ +------- Vcc to 555 and 4017 and relay
| c\ /e
| ---
| |
| [1K]
| | Dx
+-o o-+------|<---Counts 0-8 from 4017,
N/O | each count thru its own
| diode (Dx)
[33K]
|
Gnd ---------+
The 33K ensures the transistor turns off when the 4017
is not counting from 0 through 8.
For your 5 minute output:
+Vcc ----+
|
[Relay]
| +---|<---Count 8 from 4017
\c |
NPN |---[1K]---+---|<---Count 7 from 4017
/e |
| |
Gnd -----+----[33K]---+
The relay needs a diode across it with the cathode
connected on the + side.
Ed
Right, so basically I connect to the npn transistor by diodes (or
leds?) with pins 1, 2, 3, 4, 7 and 10
Yes those are the correct pins, but you need to add
more pins - pin 9 and pin 10. That will give you
counts 0,1,2,3,4,5,6,7, and 8. Each count stays
active for 2.5 seconds, so the timing cycle is
2.5 * 8 = 20 seconds. Each output (count) goes +
for 2.5 seconds. The output is connected through
a diode, and the cathodes of t6he diodes are connected
together. The base of the NPN is connected to the cathodes
through a 1K resistor.

Groan - you wanted 2.5 minutes, not seconds. Change the
word seconds to minutes above. Correction to the 555
components appears below. Also, I added 1 pin too
many. You want counts 0,1,2,3,4,5,6 and 7, so you need
to add pin 10 (not pins 9 and 10 - do not add pin 9).


The collector of that NPN is connected to the plus
side of whatever power supply you are using. The power
supply needs to be between 5 and 15 volts. The emitter
of that NPN provides power for the 4017, the 555 and the
relay.
No, use pins 6 and 9.

^^^ ^^ ^^
Yes, use pins 5 and 6


They are connected to 2 more diodes.
Those two diodes als have their cathodes connected to a 1K
resistor, and the other side of that 1K resistor is connected
to the base of another NPN transistor. No opto isolator is
needed or used.
You will use pin 9, but you won't use pin 11
No - see below.
The base of the NPN, through a 1K resistor.
For a diagram of the 555, see this url:
http://www.doctronics.co.uk/555.htm#astable
You will select R1, R2 and C to set the timing for
~ 2.5 seconds. Start with R1 = 33K and use a 50K
pot for R2. For C, use a 33 uF electrolytic.
You can adjust the pot to "fine tune" the 2.5
second pulses that the 555 will produce.

Aaargh! I figured the timing components for the 555
based on seconds, not minutes. Change R1 to 330K,
R2 to a 500K pot, and C to a 220 uf cap to get 2.5
_minute_ timing.

Ed


You can also find a diagram of the 4017 at
http://www.doctronics.co.uk/4017.htm
Connect the output (pin 3) of the 555 to the clock input
of the 4017 through a 1K resistor.
If this is not clear, I can email a jpg schematic
to you.

lol i fell asleep sending an email again... didnt see your latest post
but the latest mail has an interesting section that the last 2 output
pins still need to be connected to the first npn otherwise the 555 and
4017 will power down.. thus i think it also needs to be connected to
another diode to the npn
to stop power coming back from the other outputs and still allow the
latter 2 to send power to both... i really need to get a breadboard
and the components..

thanks for the better pictures and diagrams in the links that helped
loads! im just awake at 14:30 ahh i got work soon :/ well catch you
later like erm 3 am? UK time :D
 
Right, an update
i have created a diagram using m$ paint with BIG thanks to ehsjr's
help on this subject!
if interested email me and i shall mail you the diagram.

this is for a time delay for the digi-safes, i think it should be
good, i was thinking of changing the npn2 for opto-isolator to break /
make the connection with the solenoid so you still need to type the
pin in etc just only works after the 15 mins are up and in to the 5
min stage..

well so we have it
 
---
What the heck...

Here's how it works:

When power is first turned on, U5-1 and U5-10 will be held low until C2
charges up through R3. That will force U5-5 low and U5-9 high,
resetting the latch comprising U1C and U1D, and U1-13 going low will
keep Q1 and K1 turned off.

U5-9 going high will also create a momentary high-going spike by being
differentiated by C3 and R4, and will set the latch comprising U3A and
U3B. U3-4 being forced high, then, will reset the counter, U2, and
disable the astable multivibrator clock oscillator comprising U1A and
U1B.

The circuit will remain stable in this state until S1 is made, whereupon
the latch (U3A-U3B) will be reset and U3-4 going low will enable the
clock oscillator and U2, allowing it to accumulate counts.

After counting for 15 minutes Q10, Q11, Q12, and Q13 will all be high.

That state will be decoded by the AND gates U4A, U4B, and U4C, with the
result being that U4-9 will go high at that time.

That high will be presented to the "D" input of U5A and, after the next
high-going transition of U2-7 will appear at U5-5, the "Q" output of
U5A.

U5A going high will set the latch U1C-U1D, forcing U1-13 high, which
will turn on Q1 and energize the relay.

One minute later, Q10, Q11, Q12 and Q13 will all go low and Q14 will go
high. Then, four minutes later, Q12 will go high and, when it does,
U4-11 will go high. That high will propagate through U5-B with the next
rising edge of U2-7 and will reset the latch U1C-U1D.

That will turn off Q1 and K1, set U3A-U3B, reset and disable U2, and
stop the clock oscillator U1A-U1B until S1 is again made and the cycle
started anew.

The clock oscillator frequency is determined by considering that if 15
minutes can cause a counter's four next-to-highest MSBs to be set:

1 1 1 1 0

then one minute later The MSB will be set:

0 0 0 0 1

and, four minutes later, the "4" bit will also be set:

0 0 1 0 1

and all that'll be needed to turn the relay on will be to decode the
"15" (1 1 1 1 0) state and, to turn it off, to decode the "20"
(0 0 1 0 1) state as explained previously.

Now, since U2 is a 14 stage binary counter and we need the MSB to go
high after 16 minutes, (960 seconds) we can make a table:

STAGE PERIOD
-------|--------
Q14 960

Q13 480

Q12 240

Q11 120

Q10 60

Q9 30

Q8 15

Q7 7.5

Q6 3.75

Q5 1.875

Q4 0.938

Q3 0.469

Q2 0.234

Q1 0.117

CLK 0.059

The period of the clock oscillator will be about 1.8RC, so if we
arbitrarily set the capacitance to 0.1µF and the period to 0.059
seconds, we can solve for the resistance:

T 0.059s
R = ------- = --------------- = 327,777... ~ 328K ohms
1.8C 1.8 * 1.0E-7F

Since the frequency (about 17 Hz) will probably need to be adjusted, a
750K pot will put it right at about midpoint of the pot's range.

JF

thanks john, i did try to email you but it bounced. im sorry this
looks like what i put in the ps on my original posting, it absoloutly
confuses the heck out of me! i see - or nand and nor gates in the
discriptions and have no idea, give me a component like i dunno erm ??
a general npn or even the 555, 4017 ic i understand that.
if you could suply a basic components list (Ed's list is basic, some
may see it crude- but it works not too many components and many the
same... helps when buying as you usually have to buy 10 of something
not just 1 resistor say. the way its composed he told me how it works
but not why it works - no, and nand etc)

ANYWAY! thanks again, someone reading this will understand and be able
to use your information, just im not in deep with electronics.
regards Ian
 

neon

Oct 21, 2006
1,325
Joined
Oct 21, 2006
Messages
1,325
On Oct 1, 1:02 am, ehsjr <[email protected]> wrote:
> [email protected] wrote:
> > right what i need is a diagram for the conditions i need... let me
> > explain

>
> > i need to press and release a NO switch and after certain time like
> > say 15 mins i need it to engage a relay for say 5 mins then disengage
> > the relay and wait for the push button again after.
> > **i could go as far as opto-isolation as it doesnt need much current
> > for switching but it does need seperation

>
> > many thanks
> > Ian

>
> > ps i seen many diagrams with this tan and other but there talking
> > beyond what need to know.. i got a strong guess i need 2x555 and
> > perhaps what they call a "flip flop" circuit unless anyone has a
> > better idea?

>
> Getting 15 minutes from a 555 reliably is tough. Instead,
> set the 555 to run astable at ~2.5 minutes, and use its
> output as the clock for a 4017.
>
> Diode or all of the 4017 outputs except count 9 to the base
> of an NPN and a 1K. An example of the "diode or" is best seen
> in the second partial schematic below. The schematics are
> representative of what you need to do, not complete. The N/O
> switch also connects to the commoned cathodes of the diodes.
> The NPN controls power to the circuit. Pressing the button
> turns the NPN on, and the 4017 keeps it turned on until the
> count reaches 9, in ~ 20 minutes. Diode or counts 7 and 8
> to another NPN through a 1K - that transistor can control a
> relay to give you you a ~ 5 minute output.
>
> NPN
> +12 ---+---+ +------- Vcc to 555 and 4017 and relay
> | c\ /e
> | ---
> | |
> | [1K]
> | | Dx
> +-o o-+------|<---Counts 0-8 from 4017,
> N/O | each count thru its own
> | diode (Dx)
> [33K]
> |
> Gnd ---------+
>
> The 33K ensures the transistor turns off when the 4017
> is not counting from 0 through 8.
>
> For your 5 minute output:
>
> +Vcc ----+
> |
> [Relay]
> | +---|<---Count 8 from 4017
> \c |
> NPN |---[1K]---+---|<---Count 7 from 4017
> /e |
> | |
> Gnd -----+----[33K]---+
>
> The relay needs a diode across it with the cathode
> connected on the + side.
>
> Ed


Right, so basically I connect to the npn transistor by diodes (or
leds?) with pins 1, 2, 3, 4, 7 and 10 and use pins 5and 6 connected to
the npn and opto-isolation device instead for switching another npn
for a relay. It’s the same as a diode but using less power than the
relay, so I figured that out its now the 555 timer connection and
circuit to the cmos chip.

The tech sheet I was looking at started from output 0, this means
pins 9 and 11 don’t use (just incase someone else finds this useful)

right the 555 pinout?
1,is gnd
2, E from npn
3, connect to hi-low on cmos
4,dont use
5,dont use
6, connect to ground?
7, connect c+r to 1
8, V+

please can you confirm I have this correct

Questions.
What do the diodes and the switch connect to on the npn, I really need
a better drawing.
I did see on the tech sheet of the cmos chip it sounds like that the
output pins give out different power or something as it suggests that
only certain pins to be used to time another decade counter cmos chip,
is this right if so do I still use diode to the npn?
this is crap pin 4 ,5 don't use meaning open. crap
 
E

ehsjr

Jan 1, 1970
0
thanks john, i did try to email you but it bounced. im sorry this
looks like what i put in the ps on my original posting, it absoloutly
confuses the heck out of me! i see - or nand and nor gates in the
discriptions and have no idea, give me a component like i dunno erm ??
a general npn or even the 555, 4017 ic i understand that.
if you could suply a basic components list (Ed's list is basic, some
may see it crude- but it works not too many components and many the
same... helps when buying as you usually have to buy 10 of something
not just 1 resistor say. the way its composed he told me how it works
but not why it works - no, and nand etc)

ANYWAY! thanks again, someone reading this will understand and be able
to use your information, just im not in deep with electronics.
regards Ian

While you might not understand it at first glance, you could
learn something from John's post, if you are interested. What
John posts is always of value, and that is particularly true
in this case. Essentially, the internal circuitry in the 4017
works pretty much the same as the circuit John posted. When
you understand what he wrote, you'll also understand what is
going on inside a 4017 - and more.

Ed
 
yes i absoloutly agree! that is why i also thanked john (not like
some who just put people down) someone who wants and has time to learn
indepth about the way it works, me personally i have many hobbies and
i also start learning some stuff and then i just give it in as its too
confusing or what might seem on the top. i have so many unfinished
projects unfinished because things are too costly or i dont have the
correct tools or just loose interest...
if someone wants to look into my latter project, was kind of
interesting all i needed was someone with a vac-forming machine and i
could of easly had a final product out of beta range, it was Optical
ornamentation "to find hidden cameras" even hidden cameras that dont
work.... its called optical augmentation
 
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