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delay 5 second NEED HELP

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surviver

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My name is maxim . I am newbie and starting to learn about simple circuit but now i got a problem that i hav no idea how to delay a pulse (active high) i am using the 4017 with 12v input power (car battery) the clock input i used car signal light to triggered . Now my question is when the output 1 of 4017 decade counter triggered i need 5 second delay and then reset back this 4017 decadecade counter let it become output 0 (high). I plan to use 555 timer to delay the pulse (maybe is always high) that from output 1 (4017) and from 555timer output (3) direct connect to Reset (4017 decade counter) i try to use this method (https://www.electronics-project-design.com/timedelaycircuit.html) but after i test with breadboard look like cannot work can someone help me ! thanks !!!!! appreaciate!!!!!!!!!
 
I am not sure I quite understand what you are doing. However for each positive clock transition the 4017 the 4017 will make one of ten outputs sequentially go high. The count takes place when pins 13 (Clock Enable) and 15 (Reset) are held Low.

<Edit> Changed 13 and 15 to Low, I wrote it wrong. </EDIT>

Now as to the 555 timer. It sounds to me like you want to configure the 555 as a "One Shot" so when the 555 is triggered on pin 2 (Trigger) it will output a pulse on pin 3 (Output) going from low to high for a time interval determined by the RC timing network. The problem is if you want to trigger the 555 from the 4017. The 4017 outputs go high but to trigger the 555 you need a high to low on pin 2. The way to do this would likely be to have the 4017 output drive a transistor (NPN) which would invert the pulse from the 4017 and trigger the 555.

Beyond that I am not sure exactly what you are trying to do? Unless you want the 555 output to delay 5 seconds and then reset the 4017? In that case the circuit you linked to should work.

However, there may be a problem. The input to the transistor would need to be held high for the duration. The 4017 will output a pulse based on the input clock duration. That may be your problem. What is the clock frequency of the 4017?

Ron
 
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thanks Reloadron
I know what is your question . First i test the 4017 decade counter when the pin 15 (reset) disconnect from GND (0v) then the 4017 will reset and pin 3 (output 0) will always high and waiting for another clock pulse signal come in. So when the 4017 pin 2 (output 1)triggered (low to high OR always high) then used this signal to activated the 555 timer for 5second delay FOR reset the 4017 means that pin15 (reset) disconnect from GND (0V). One question after activated 555timer delay 5 second pulse for 4017 pin15 (reset) Can i used 4017 pin 3 (output 0) to reset back the 555 timer means that let the 555 timer output (pin 3) become low(If triggered HIGH).Purpose for me to used 555 timer it just wan to delay 5 second to reset 4017 issit got another better way to reset 4017
Actually the clock frequency i tap from car signal light (but now testing in the breadboard).So i used a RELAY to generated pulse means that when NC (normally close)i connect to GND (0v) NO connect to high (12V) the common pin i join to 4017 pin 14 (clock signal) means that when car signal light triggered (pulse HIGH)to activated the relay to create pulse for 4017
Can i used transistor or other to generated a pulse instead of RELAY ??
 
See my edit above, I had that backwards. Sorry and my bad on that note.

Let me think about this and get back to you.

Ron
 
Yes. A transistor can be used instead of a relay to provide the trigger pulse.
 
hi alec_t
my incoming signal is active high (pulse 12v) but this signal not suitable to used for 4017 clock signal.
Do u got any diagram for me to reference ??? thanks!!!
 
my incoming signal is active high (pulse 12v) but this signal not suitable to used for 4017 clock signal.
What is the supply voltage (Vdd) of your 4017? Standard 4000 series CMOS (not the HC type) has a supply range of 3V-15V, so 12V could be OK to clock it. If Vdd is less than 14V(the maximum car battery voltage) then a simple voltage divider may be all that you need.
 
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alec_t
Thanks for your prompt reply

If i used Car signal light as my clock input (4017 decade counter) the problem is the signal only supplied me pulse (high). But as far as i know the clock input (4017 decade counter) need to either LOW (gnd) or High (12v) to run it. Now my question is how to used transistor for always supply Low signal (gnd) for clock input (4017) and wait for pulse (high) coming in . Now i used a RELAY to generated pulse means that when NC (normally close)i connect to GND (0v) NO connect to high (12V) the common pin i join to 4017 pin 14 (clock signal) means that when car signal light triggered (pulse HIGH)to activated the relay to create pulse for 4017 . But i found that using Relay for generated pulse signal is not a good idea so i wan to tried another way which using transistor instead of relay . If can , can you give me a diagram to be reference
 
If i used Car signal light as my clock input (4017 decade counter) the problem is the signal only supplied me pulse (high).
I'm not sure what you mean by 'pulse' in this context. Which light provides the signal? Are you referring to a single 12V pulse which has its leading edge when the car head-lights (say) are switched on and then remains at a steady 12V; or a 12V signal which pulses as the left or right indicator light blinks?
If the signal is a steady 12V and is used to clock the 4017 the 4017 will only count up once, so something else would be needed to create a series of clock signals (which is what I think you want?). But the left/right indicator light could provide such a series.
 
Hi alec_t thanks for reply appreaciate
The pulse is provides from signal light ( left / right ) NOT head light. As far as i know when i testing inside the car the pulse (signal light ) only give me active HIGH means that is not suitable for me direct put it into clock pulse (4017) because when no pulse coming in is NOT 0V (gnd) . What i wan is when the driver TURN ON signal light when the FIRST pulse coming in i wan to used this signal to ACTIVE a relay , SECOND pulse come in DEACTIVATE the relay . IF more than two pulse i will reset the 4017 .
My question is how to used transistor to generated the pulse which suitable for me to put it in clock signal (4017) . Which mean when the driver din't SWICTH ON signal light , the clock input (4017) can get 0V (gnd). When SWITCH ON the signal light give me the pulse (active high) signal .
NOTE : PULSE from the vehicle ( signal light ) when NO activated the current floating ( NO gnd or 12V )
 
PULSE from the vehicle ( signal light ) when NO activated the current floating ( NO gnd or 12V )
I'm puzzled as to where you're picking off the signal. Is this light the one on the dashboard? If so, it may be powered directly from an MCU output. In that case it almost certainly would not be safe to try driving a relay directly with it.
It would also help to know if the car 12V supply is also the supply voltage for the 4017 ?
 
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Hi elec_t
I'm NOT directly picking the signal from MCU output . The signal output i picked from signal light which mean ' BULB' there . I tried before that's safe . But of course i not directly to driving relay i used transistor to control the signal for relay .
The main 12v supply voltage is from car battery also . Is it will damage the 4017 or 555 timer ?? ( I haven't tested yet ) But the main power there i got add regulator and resistor to drop the current flow .
Same question : how to used transistor to generated the pulse which suitable for me to put it in clock signal (4017) ?
thanks
 
i used transistor to control the signal for relay
Then the same transistor, connected as an emitter-follower, can be used to clock the 4017. If you're planning to use a voltage regulator to drop the ~12 volts down for supplying the 4017 and 555 then tap off a fraction of the voltage at the emitter so that the tapped-off voltage is slightly below the logic supply voltage.
 
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