1000 Threads found on edaboard.com: 555 Timer In Orcad
Hi guys ,
I am trying to simulate the standard astable oscillator using 555 timer, in circuit maker. But i am not getting any oscillations at all. Could you guys please help me out.
The circuit is the same that you find in most of the 555 timer books .(operation in astable mode)
Software Problems, Hints and Reviews :: 04-16-2008 15:51 :: VASANSNS :: Replies: 0 :: Views: 1390
I've seen realistic results out of LTCSpice using the model
off their Yahoo! user group repository.
You should be aware that the 555 does not produce truly
square (50/50) output for most sensible RA/RB ratios.
Read the app notes if this matters to you.
Analog IC Design and Layout :: 10-18-2010 09:06 :: dick_freebird :: Replies: 2 :: Views: 2184
i've just registered and have a emergency question .
i modeled a astable multivibrator with 555 timer in orcad but it showed this error
convergence problem in bias point calculation, then i enabled skip the initial tran... but now i see this error!"There are no data values in section #1 ignoring this section"
Electronic Elementary Questions :: 10-31-2012 08:22 :: fatemehgh :: Replies: 1 :: Views: 438
hey i don think we can implement 555timer in verilog or vhdl...you can possibly realise its functionality... like if you want a astable multivirator or bistable one... you can realise it i suppose...
PLD, SPLD, GAL, CPLD, FPGA Design :: 12-04-2007 00:44 :: lordsathish :: Replies: 3 :: Views: 2965
my college project requires me to build a 555 timer based LCR meter, so can i possibly replace the LM311 oscillator with the 555 timer in LC meter circuits
Electronic Elementary Questions :: 11-08-2011 07:42 :: philcul :: Replies: 2 :: Views: 1710
How can I use a 555 timer IC and LM 386 in ADS? is there built in ICs or do I have to design them my self? and where can I get the schematics of the ICs?
Analog Circuit Design :: 12-17-2011 14:30 :: dumborambo :: Replies: 1 :: Views: 764
Just a question regarding triggering of a monostable 555 timer, what will happen if I pull down the trigger of the monostable circuit to the ground on the ouput?
Say, I trigger it (put trigger pin to ground) and will just put it on ground (not release it), what will happen to the output? Will the monostable do its normal operation or it will jus
Electronic Elementary Questions :: 10-09-2006 01:10 :: glenjoy :: Replies: 8 :: Views: 6363
Need help please...........
is it feaseable 2 use a 555 timer in place of LM3909 to produce oscillations and how do I go about it?
Hobby Circuits and Small Projects Problems :: 10-14-2006 09:10 :: polag :: Replies: 5 :: Views: 4819
In the following timer circuit's block diagram whenever threshold pin is greater than 2/3 of Vcc and trigger is greater than 1/3 of Vcc. We have R=S=1 .............but we know that R=s=1 is an indeterminate state in R-S flip flop. In this case
what would be the output ?
is it possible to have R=S=1 inside the flip flop of 555 (...)
Electronic Elementary Questions :: 02-19-2009 06:12 :: desperado1 :: Replies: 5 :: Views: 723
i think there is a way of getting this...the babani book on the 555 timer is the best reference on 555's
Or the 555 datasheet has a lot of application circuits.
it may depend on the frequency though.....i.e. at high frequency it may not be practical
Power Electronics :: 10-16-2011 13:08 :: grizedale :: Replies: 1 :: Views: 569
Im using the AM Transmitter and Receiver Pair along with the RF600 enoder and decoder.
I have constructed my PCB, the output is going to a 555 timer with a basic pair of LEDs and a buzzer.
At the moment when I press the learn switch the status LED on the decoded goes on but when I let go, it goes off again.
I have this working on breadboard w
RF, Microwave, Antennas and Optics :: 10-02-2005 14:06 :: mhamini :: Replies: 0 :: Views: 486
I have an analog circuit with a 555 timer outputting 0 to 5V, but what I want to do is switch the high's and lows. In other words when the 555 outputs 0V, I want it to output 5V and when it outputs 5V I want 0V. Inverters only seem to flip the signal around the 0V axis (multiplying the signal by -1)
A "picture" may describe (...)
Analog IC Design and Layout :: 02-08-2007 18:51 :: trackst4r :: Replies: 2 :: Views: 735
I am using a monostable multivibrator in my project,,which is implemented using 555 timer.But the problem is when i switch any thing in power line, the multivibrator jumps to its unstable state and it starts mislatching,,interesting thing the project has no concern with power lines .Plz help me how can i avoid this??
Electronic Elementary Questions :: 03-25-2009 14:38 :: Adil Israr :: Replies: 2 :: Views: 798
what is the main purpose of discharge pin in 555 timer ?
Electronic Elementary Questions :: 01-16-2012 11:38 :: dinesh401 :: Replies: 2 :: Views: 2065
Can anybody help me explain with the use of an 555 timer IC in designing a digital sensor with a modulating sensor?
I do not know what you call a "digital" and "modulating" sensor. The 555 timer can be used as a timer, an astable or monostable multivibrator, a PWM generator, etc.
Please explain exactly (...)
Analog Circuit Design :: 11-19-2013 05:23 :: jiripolivka :: Replies: 1 :: Views: 243
In schematics for the 555 timer Chip in Schmatics they do not show the hookups as
1, 2, 3, 4, and 5, 6, 7, 8 in vertical sequence. Many scchematics illustrate
the sequence of leads on the chip as all mixed up. The draw is clear, but the sequence as to the chip is all mixed up.
How does that help?
Electronic Elementary Questions :: 11-05-2014 10:54 :: ScholarGypsy :: Replies: 1 :: Views: 225
You can for example look here:
for a 555 controlled sawtooth generator.
Hobby Circuits and Small Projects Problems :: 03-02-2004 10:34 :: C-Man :: Replies: 5 :: Views: 8466
a 150W switchmode power supply with 555 timer:
it cheapest method to design such switch mode power supply.
Analog Circuit Design :: 05-24-2004 01:32 :: alphi :: Replies: 14 :: Views: 18318
you can get many many reference designs with 555 timer from books or website.
pls search it in library or www.
Electronic Elementary Questions :: 10-10-2004 23:07 :: ljkong :: Replies: 5 :: Views: 982
For 1), you can use two 555. The first one as a monostable and the second one as an astable. The astable period be the blinking period of the LED diode. The monostable period should be 5 second. The monostable output (3) should be connected to the reset pin (4) of the astable.
Electronic Elementary Questions :: 10-18-2004 07:17 :: papyaki :: Replies: 7 :: Views: 1731
What you do is have it in the astable mode with a speaker in series with a capacitor. These tow are placed one end to ground and one end to the 555 output (this is for a CMOS type. IF the output is an open collector, use a pull up resistor.) Then have the remote button be between the power supply and the +V power supply pin of the 555.
Analog IC Design and Layout :: 04-10-2005 20:08 :: flatulent :: Replies: 1 :: Views: 2118
Be carfull when planing long timming periods from a 555 timer . The circuit shown relies on a 1000uf capacitor. This is a component with a high leakage current and I would recomend a tantalum capacitor or a none electrolitic equivelent. Even so it may appear to work when first constructed but may well change duo to ageing and enviromentl factors
Analog Circuit Design :: 05-06-2005 06:36 :: barrybear :: Replies: 10 :: Views: 1837
It's called timer because of its use in timer applications such as square wave generation ...etc.
And the name "555" is because of the three 5kOhms resistance in its input (check its internal block diagram)
Hope that helped,
Electronic Elementary Questions :: 04-27-2006 18:57 :: ahmad_abdulghany :: Replies: 4 :: Views: 704
You can simulate the 555 in circuit maker 2000 infact there is an example circuit which demonstrates the simulation of the 555 IC in the astable mode.
I am attaching the 555 example file and a screenshot of the simulation.
Software Requests :: 05-09-2006 08:04 :: ibrahim03 :: Replies: 7 :: Views: 1681
i need a circuit for Phase shift keying.... a circuit using 555 timer would be much helpful...
Electronic Elementary Questions :: 08-06-2006 06:56 :: A.Anand Srinivasan :: Replies: 3 :: Views: 1623
Basically you need to use the 555 timer in MONOSTABLE mode. See one of the many links on that circuit of this link and scroll down to Monostable circuits
Make sure to read and understand the section under More about triggering
to avoid any trigger possibilies coming from the back (re
Hobby Circuits and Small Projects Problems :: 08-26-2006 04:20 :: unkarc :: Replies: 4 :: Views: 1969
Yes, The name of 555 came from the three 5kOhms resistors at its input!
important or not, it's not clear :) as they're a part in the IC structure! and according to them it works !
I hope that helps :)
Electronic Elementary Questions :: 12-20-2006 06:57 :: ahmad_abdulghany :: Replies: 5 :: Views: 7506
use 555 as ramp generator, see datasheet NE 555
Professional Hardware and Electronics Design :: 02-18-2007 09:21 :: Kurniawan :: Replies: 5 :: Views: 2239
You may like to take a look at this circuit,
generating PWM signal using 555 timer.
Electronic Elementary Questions :: 03-15-2007 09:43 :: siongboon :: Replies: 4 :: Views: 6876
Have a look at:
There is a Relay Toggle Circuit Using a 555 timer.
Electronic Elementary Questions :: 08-26-2007 06:21 :: dunn :: Replies: 15 :: Views: 4602
Connect 4 x LM555 timers in the following sequence: RED(long), Yellow(shorter), Green(long) and Yellow again and close the loop by feeding the input of the first 555 from the output of the fourth 555 ..
Here are examples:
Electronic Elementary Questions :: 09-17-2007 11:01 :: IanP :: Replies: 2 :: Views: 2897
ok so my teacher wont accept the fact that the circuit he has told everone to use isnt even going to work... he has refuses to let us make our own but i dont realy care as it isnt reght that we all have to use the same circuit cos its easier fr him...
so if anyone has any clues of what way i would go about doing this please tell me
Hobby Circuits and Small Projects Problems :: 09-28-2007 06:25 :: devildonebad :: Replies: 3 :: Views: 1392
if you are using potentiomenter, then you require just one potentiometer and a diode with 555 astable multivibrator circuit
Hobby Circuits and Small Projects Problems :: 12-02-2007 06:39 :: yogi :: Replies: 5 :: Views: 4234
555 is an analog chip based on op amps and use the values f external components to select it's mode and timing .
I think this can't be done in vhdl!!!!
PLD, SPLD, GAL, CPLD, FPGA Design :: 12-09-2007 20:07 :: alzomor :: Replies: 2 :: Views: 1520
Hi, I want to use 555 timer in orcad pspice 9.1 (student version).
I downloaded the files from internet:
and copy them to the directory:
However, when I simulate a circuit of 555. there is an errro: (...)
Hobby Circuits and Small Projects Problems :: 03-27-2008 12:16 :: Beardolphinaries :: Replies: 3 :: Views: 13333
I want to build a function generator by using 555 timer for signal generator and it capable of outputting a square wave with adjustable frequency in the ranges of 1Hz to 100Hz..
If anyone have an idea please let me know...thanks for your cooperation..:D
Hobby Circuits and Small Projects Problems :: 09-14-2008 20:53 :: harazazi :: Replies: 3 :: Views: 10936
Yes, it is possible, but you need more than one 555.
Can you describe the application a little better?
Analog Circuit Design :: 10-09-2008 12:27 :: VVV :: Replies: 4 :: Views: 897
Hi guys!! I am a hobbyist and my current requirement is to actuate a coil of approx 300mH with the help of a 555 timer IC or an 8051 or atmega8515 AVR microcontroller (as I require variable PWM). definitely I will be needing an amplifier gain stage in between and I am planning to use ULN2003 for it (with paralleled inputs and paralleled outputs for
Hobby Circuits and Small Projects Problems :: 01-21-2009 00:39 :: berry-o :: Replies: 2 :: Views: 1592
It doesn’t make any difference which pole you label with (0)V ..
That is the matter of convenience and/or convention ..
For as long as the 555 “sees” the right polarity your circuit should work just fine ..
Analog Circuit Design :: 06-10-2009 08:36 :: IanP :: Replies: 4 :: Views: 2034
how can i make the 555 timer IC work as a PLL, do somebody have a circuit diagram for this job?
Take a look at
There is a circuit for PLL Application – Frequency Demodulation
I hope it is helpful
Professional Hardware and Electronics Design :: 11-25-2009 10:30 :: bicho :: Replies: 5 :: Views: 3599
Googled: 555 calculator
Electronic Elementary Questions :: 02-07-2010 13:40 :: KMoffett :: Replies: 3 :: Views: 922
Linear Technology (link above) offers totally free simulator ..
It comes with a model of the 555 and I think it has 555 simulation examples to get you started ..
On the other issue, inverting output wave in 555-timer is so easy only beacuse the output can do both: sink and source c
Electronic Elementary Questions :: 02-16-2010 19:43 :: IanP :: Replies: 11 :: Views: 6237
to reduce the current consumption , when LEDs are off is
to include a transistor in series with + line and controlling its base voltage with the sample from pin3 of 555.
in which case the switch SW1 may be moved across the series transistor .
Hobby Circuits and Small Projects Problems :: 08-10-2010 10:04 :: srizbf :: Replies: 3 :: Views: 2808
I wouldnt use any of those for your application.
You want a loud buzzer, well you can get a cheap piezo that'll produce 100db's, which is annoyingly loud, getting that from your own circuit requires complexity.
I'd use the above piezo on a monostable to give the time delay.
A standard monostable 555 circuit would work fine, you'd need a 22
Hobby Circuits and Small Projects Problems :: 08-23-2010 23:39 :: dr pepper :: Replies: 1 :: Views: 1668
You can use a 555 timer in a monostable mode to get the desired effect. Check out this page, under monostable, and using the circuit modification mentioned in "Power-on reset or trigger" (cap in parallel with power switch)
555 timer circuits
The basics of why this works is detail
Electronic Elementary Questions :: 03-07-2011 21:41 :: enjunear :: Replies: 16 :: Views: 7668
You're mixing three losely related points in your last post. Consequently there's no reasonable answer to it.
Referring to your original question, the modulation input is varying the threshold of the comparator ending the output pulse. Insofern, the instantaneous value of AC voltage matters, it's like being sampled. Unfortunately, the modulaion
Analog Circuit Design :: 07-11-2011 06:54 :: FvM :: Replies: 5 :: Views: 1830
can anyone explain the relationship between control voltage and pwm output of a 555 timer.
searched a lot but could not get one.
Analog Circuit Design :: 07-26-2011 03:28 :: kishore3677 :: Replies: 26 :: Views: 5893
There is a Vcc power supply pin (#8) for the 555 and the note above refers to the voltage applied as power supply to that pin, the listed parameters are given with a power supply in the range of +5 to +15v
Electronic Elementary Questions :: 07-28-2011 07:01 :: alexan_e :: Replies: 7 :: Views: 506
There are many ways to built a 7 segment clock/timer project. Most of the circuits don’t include a 555, in this kind of projects need more accurate timings, so better to use quartz controlled oscillators. Please clarify why you have considered using 555 timer as a must for this application.
Electronic Elementary Questions :: 07-28-2011 16:34 :: mister_rf :: Replies: 5 :: Views: 9091
If you are going to incorporate a microcontroller (MCU) into your design, there is no need for a 555 timer. Most MCUs have one or more timer/counters which can be used to produce a delay.
Do you have a particular MCU you were considering for your design?
Microcontrollers :: 09-11-2011 05:38 :: bigdogguru :: Replies: 6 :: Views: 1051