54 Threads found on edaboard.com: Noise And Zener
i want to use clipper circuit in my low noise circuit. the options are to use zener diodes or tvs. But thier noise dayta 9noise floor, etc0 is not quantified by suppliers nicely. Can anybody guide me pertaining to this?
Analog Circuit Design :: 20.06.2007 01:30 :: rajesh keshwani :: Replies: 1 :: Views: 1643
i want to analyze the noise performance of my circuit,but i can't find any noise sources in pspice and i need pink noise and white noise source~~
so ,how to make it in pspice?
Electronic Elementary Questions :: 06.04.2008 11:35 :: ZengLei :: Replies: 2 :: Views: 2112
There are projects that produce white noise, and from more than one type of device.
Some use an NPN with emitter-to-base operated in zener mode, or a zener diode, or a cheap noisy op amp. This method may or may not be available in simulator programs.
There are also commercial chips whose purpose is to generate white (...)
Digital communication :: 16.05.2012 03:54 :: BradtheRad :: Replies: 6 :: Views: 394
hi to all,
i am doing a project on 8051 which includes the controlling of the 12v DC motor using a relay......
so i need to a help in reducing the noise and back emf which is generated by the DC motor......
Microcontrollers :: 15.02.2013 08:45 :: jjeevan007 :: Replies: 7 :: Views: 513
you can make one from a 5v or 6 v miniture light bulb
just blow the filliment with 12 v paint it with conductive paint paint in a small conductor
and use this too provide a field signal
any field signal is white noise connected too a bjt
some instuments use this approch
but this isnt a special one
Professional Hardware and Electronics Design :: 19.03.2003 21:45 :: THE BORG :: Replies: 4 :: Views: 990
1. you can use LFSR generate a digital serial random bit stream ,
I ever use it , but you should be care for how to testing it ??
--> easy implement , but not really random number ,
because chip reset will get the same ID ..
2. Intel use device noise and modulation a oscillator ..
you can (...)
Analog Circuit Design :: 22.03.2004 20:50 :: andy2000a :: Replies: 7 :: Views: 1841
I wonder how may a resistor connected series with an adc affect the measuring performance? Does it help to improve accuracy or reducing noise? Or what effects can it have?
Professional Hardware and Electronics Design :: 27.10.2004 00:23 :: seyyah :: Replies: 4 :: Views: 1321
In some systems, system done ESD test is in power on condition.
When ESD shooter discharges, it occurs huge noise inside chip.
How do you deal the noise of system ESD test?
How do you keep the chip function can work fine?
ASIC Design Methodologies and Tools (Digital) :: 12.06.2005 00:46 :: jiang :: Replies: 3 :: Views: 439
usually the term noise means white, gaussian distribution. But your question sound as different meaning. Do you ask for white, gaussian noise or for randomatic sparks discharge?
RF, Microwave, Antennas and Optics :: 20.01.2006 17:16 :: sergio mariotti :: Replies: 3 :: Views: 777
I'm Attempting to convert a Playstation 2 power supply from a single rail 12v supply to a 2A constant current supply to drive a stepper motor. I have been unable to find a circuit diagram for the item but I have been able to deduce a few things. ( If anybody has a copy of the circuit feel free to let me know :), )
I have worked
Analog Circuit Design :: 22.07.2006 19:28 :: canon99 :: Replies: 1 :: Views: 2368
Please suggest some circuits or sites which have info regarding white noise generator.
Thanking you all
Analog Circuit Design :: 17.09.2006 13:05 :: Venkata Krishna :: Replies: 1 :: Views: 671
i want to use clipper circuit in my low noise circuit. the options are to use zener diodes or tvs. But thier noise data (noise floor, etc) is not quantified by suppliers nicely. Can anybody guide me pertaining to this?
Analog Circuit Design :: 05.07.2007 07:37 :: rajesh keshwani :: Replies: 6 :: Views: 593
I've seen zener diodes and reverse polarised BE junctions folowed by amplifiers used as noise sources in some simple test equipment (home made).
For better performance use a pseudo-random binary sequence (PRBS) generator connected to a DAC.
Look in The art of electronics - Horowitz, a chapter is about PRBS generators (...)
Analog Circuit Design :: 07.09.2007 14:40 :: Eugen_E :: Replies: 3 :: Views: 615
Do any one of you have experience in genearion of noise?
(making a noise source that is generation of noise signal at any frequency).
I am interesting in generation of white noise.
Can any one help me & suggest me
RF, Microwave, Antennas and Optics :: 18.10.2007 07:03 :: Abhishekabs :: Replies: 6 :: Views: 521
How to build a simple white noise generator ?
i want to build a simple one ,so i can understand the white noise thoroughly.
any suggestions or circuitry?
Analog Circuit Design :: 25.03.2008 05:15 :: ZengLei :: Replies: 7 :: Views: 14175
Hi I have previously posted here but did not get any replies. I wanted to know whether there is anyway of producing a noise source in a breadboard circuit. I have already tried using a zener diode in a reverse biased direction but it did not produce any results. Can anyone please help me out? Thanks
Analog Circuit Design :: 25.02.2009 04:45 :: niloy2k :: Replies: 14 :: Views: 1190
I would recommend this. Slightly more elegant than a zener and resistor. zener wants to be around 9.3 volts. NPN power transistor, heat sink it if you are taking out significant current. If you need low output noise, put a .1 uF in parallel with the zener.
Analog Circuit Design :: 01.10.2009 13:41 :: biff44 :: Replies: 5 :: Views: 1033
I'm working on a system for measuring position. I have a sensor, it is magnetic encoder and it sends data (quadrature signals A,B) to MCU.
I want to ask if it is good idea (in term of noise) to connect the sensor directly to MCU if the sensor is away
Hobby Circuits and Small Projects Problems :: 14.01.2010 17:38 :: luckym :: Replies: 2 :: Views: 1341
I have a problem finding information on the subject of noise level relationship to current flowing through a HV zener in the breakdown mode.
Somehow the manufacturers don't elaborate on the noise issues in zeners.
The only graph I found so far is Fig. 2 in the 5612568 patent.
I'd post a link to it, but I am new, so the (...)
Electronic Elementary Questions :: 10.12.2010 18:00 :: 2345 :: Replies: 1 :: Views: 405
The problem formulation makes clear, that only a simplified calculation is needed. No exact transistor or diode characteristics, just nominal didoe and transistor forward respectively saturation voltages. It's going like this:
- determine Vo(high) and Vo(low)
- because separate Vi(low) and Vi(high) voltages can't be determined in the (...)
Analog Circuit Design :: 13.05.2011 13:56 :: FvM :: Replies: 9 :: Views: 703
Would be helpful if you post a schematic on this.
1. Do note that for any power electronic devices, switching loss is not the only cause of power loss and usually very small percentage. I believe the major contributor of heat comes from the conduction loss. Maybe you can measure and check the input current and output current of the IGBT (...)
Power Electronics :: 16.06.2011 12:43 :: SkyHigh :: Replies: 74 :: Views: 3807
You can use transient suppressor and zener diode on main +5V power supply from which you branch out supplies depending upon noise levels
Analog Circuit Design :: 29.05.2012 07:24 :: abhi_tandon80 :: Replies: 1 :: Views: 233
Yes , I agree with you.usually suppressors used for damping noise effects and surge. please check size of your component and compare with datasheet.
and so this component placed in inverse direction like zener.
Service Manuals, Requests, Repair Tips :: 23.06.2012 00:25 :: davoud :: Replies: 3 :: Views: 345
Dear friends ,
I have come up with a problem ...... when i drive the ac motor with contactors by manually pushing the coil tab , The motor runs and i c a lot of noise being generated on the ac power line (it reflects on a power supply of 7805 5Volts , though i have used capacitors across its output ,10uF, 1uF, .1uF etc.
The contactors are
Microcontrollers :: 11.08.2012 12:12 :: jit_singh_tara :: Replies: 3 :: Views: 275
The noise is produced because you are reverse biasing the EB junction. It then behaves as a zener diode of about 5v.
Every zener diode produces noise when you "starve" it. That is, when it is operating near the knee region of its characteristic curve. At less than the recommended current.
There is a distinction between low (...)
Electronic Elementary Questions :: 30.09.2012 11:36 :: albert22 :: Replies: 5 :: Views: 512
I have designed a circuit to operate in a CAT Loader. This is not a modern CAT, but one from the 1980's. These Loaders run on 24V batteries. I was planning on just hooking a LDO linear regulator up to this supply. After a perfectly operating board was installed(Note: 3.3v system), the LDO was overcome by noise and did not output a voltage.
Analog Circuit Design :: 11.11.2012 20:17 :: Joeisi :: Replies: 3 :: Views: 189
I need to eliminate the noise from DC circuit.here is attached circuit.85067
I got the distored waveform acrose 7.5 K resistor.
Please help me to remove the noise, i have place the ceramic cap of value 100nf in parallel with 7.5 K resitor, but the still issue is remains same.
please help me out, i am very new in Pow
Professional Hardware and Electronics Design :: 01.01.2013 06:21 :: SurekhaIris :: Replies: 4 :: Views: 359
The fluctuating could be casued by noise in circuit, Try placing a 10uF cap on the input of the pin your measuring (RA0) of the micro. I've always place the crystal on the outside never seen mounted like picutre not sure what effect this would have but I would say it's more noise related
Microcontrollers :: 17.02.2013 12:55 :: wizpic :: Replies: 9 :: Views: 1450
I'm working on designing a noise generator, and I was hoping I could get some info on the characteristics of diode noise--specifically noise in a zener diode operating in reverse breakdown. Here are my basic questions:
1.) What are the characteristics of diode shot noise? (...)
RF, Microwave, Antennas and Optics :: 25.02.2013 16:53 :: SparkyEngineering :: Replies: 3 :: Views: 361
I have 15V and I need a 5V and I am using a LM340 to give me the 5v. Since the voltage differential is 10v and my current usage is 0.1A. That is a lot of heat on the regulator, Very hot when you put your finger on top of it. Is there any simple way to lower to 15v to 7v and solve my heat problem. I don't want to use (...)
Hobby Circuits and Small Projects Problems :: 20.07.2003 23:08 :: ahgu :: Replies: 14 :: Views: 2429
u will need one inductor and capacitor to reduce ignition noise.
Many car audio devices hv this inductors built in their power cable.
Hobby Circuits and Small Projects Problems :: 27.02.2004 10:34 :: palesha :: Replies: 14 :: Views: 3168
Look for TL431 datasheet in the web (TI or other manufacturer!), there are several useful hints for your problem like using shunt regulator to control voltage like a zener diode, for this u need a band gap reference a wideband comparator and a NMOS!
also u can use two stage regulator; one for input (...)
Analog IC Design and Layout :: 10.06.2004 05:19 :: goodboy_pl :: Replies: 1 :: Views: 1250
What is a MOV?
It is a crystalline material which has a bidirectional IV characteristic like a zener diode. It is used to reduce the effects of transients on the line it is across.
The noise that is generated in the post two above is due to some piezoelectric effect. You should examine the data sheet for the MOV and see i
Hobby Circuits and Small Projects Problems :: 10.08.2004 16:22 :: flatulent :: Replies: 4 :: Views: 972
A Varistor is a device that is capable of resistive conduction once a specifice voltage is reached. Its purpose would be to reduce the electrical noise that a dc motor may induce on to the power supply.
Robotics and Automatics Forum :: 16.09.2004 07:28 :: barrybear :: Replies: 6 :: Views: 2643
Does anybody know where to get a Matlab file that generates very close to independent random samples? If you look at the higher order statistics of rand or randn, they are not as independent as I would like them to be. Any suggestions?
inorder for u to generate random numbers, u could use the PN sequence generator,
Digital Signal Processing :: 08.03.2005 14:59 :: cedance :: Replies: 12 :: Views: 2435
I guess you CAN'T! All that you can do with logic gives you more or less PSEUDO-RandOM sequences.
True random sequence can be generated using the help of noise generator. There is an application note on the web (can't recall the magazine nor the name of the article right now, sorry) that uses zener diode as (...)
ASIC Design Methodologies and Tools (Digital) :: 23.05.2005 17:26 :: rfmw :: Replies: 5 :: Views: 3174
zeners at 5.6V normally have a low coeff while > 5.6 have a positive coeff, and < 5.6V a slight negative coeff. That is the reason why you will often see 5.6V zeners used in voltage reference circuits.
Also there's a rule of thumb to never design with zeners at operating currents below about 5mA. If you do you may get (...)
Electronic Elementary Questions :: 02.03.2006 10:40 :: E-design :: Replies: 14 :: Views: 1107
Hi all..I have a PSU outputting 5Vdc..but when there's interruption in the 240Vac mains, i get spikes on the 5V rail..the spikes can be around 12-16Vpp and sometime burst to 40Vpp..the spikes occurs at random frequencies..could anyone suggest me on how to filter these spikes..? i manage to somewhat reduce the spikes by putting a choke at incoming n
Analog Circuit Design :: 08.02.2006 05:41 :: mayu_wakui :: Replies: 15 :: Views: 1335
It is easy man, think about this... each leg of microcontroller has two protection diodes (zener), if the applied volatge is over 5 volt, let us say 220 Vrms, then the zener will cut it to 5 volt, and if it is -220Vrms, then the another zener will work in forward and make the volatge almost zero.
Microcontrollers :: 18.04.2006 06:00 :: hjamleh :: Replies: 5 :: Views: 3582
I need to design a high gain receiver that must be able to withstand (block) high voltage (350 V) pulses (the receiver must amplify the very small signals that follow this pulse).
Any idea on how to block the high voltage pulses in order to protect the receiver? Originaly I used a resistor and a pair of diodes, but the resistor generates
RF, Microwave, Antennas and Optics :: 11.05.2006 14:47 :: cyberblak :: Replies: 5 :: Views: 776
It depends on your requirement.
If you need a low noise converter, LDO is good.
If efficient or heat generate is important, DC/DC is good.
If just need a voltage conversion, just us resistors.
Analog Circuit Design :: 13.09.2006 05:40 :: SolarTorch :: Replies: 19 :: Views: 2695
I have generated Pseudo noise using a PIC 12c672 .Basically is having arrays . You can tap the array and exor it with a value. The sequence will repeat atfer some time, but looking it into an spectrum analizer it was enough for my purposes (apply this noise to a laser) .
Microcontrollers :: 18.12.2006 14:17 :: rfguy1 :: Replies: 7 :: Views: 964
My 32-bit secure processor needs the following power supply lines:
- 3.3v (for IOs) VIO
- 1.8v (for the digital core) VCORE
- 1.8v (for the battery backup registers) VBAT
By default my product is turned off and only the battery backed unit (3v) is used through a 1.8v regulator to maintain the specific registers of the secure area
Analog Circuit Design :: 19.07.2007 09:53 :: lionelc :: Replies: 0 :: Views: 440
I have a different question in mind,related to 4-20mA signal. We have hundreds of instruments from different make installed into the Re-heating Furnace for Galvanzing line. The furnace is from TENOVA Hypertherm. It's not been set yet. It's under errection. Their engineer is with us these days. He once told me, we use current for analog input agains
Analog Circuit Design :: 25.12.2009 10:16 :: umery2k75 :: Replies: 7 :: Views: 2304
It's a copy of radmor secure system, but with "present time" components, that works very well.
System is made to secure power amp and column loud speaker. Works with almost all kinds amplifier, all costs are very low.
Show DIY :: 16.12.2009 05:58 :: gres :: Replies: 0 :: Views: 719
Usually a gate to source resistance is provided to prevent accidental turn-on due to noise or other factors or gate-to-drain internal capacitance (Miller capacitance). Normally I use 1k and it always works fine.
There is no need to put MOV across the resistance. Instead place a zener diode for providing gate-to-source protection from (...)
Power Electronics :: 11.01.2010 11:54 :: Tahmid :: Replies: 7 :: Views: 3736
the problem is the soding great 4001 diode
you must use a schottky diode like a bat 85
not a silicon rectifier thats too slow
and will present slew to the slew ridden opamp
redesign around this
and post again
you can always add two in parallel to get the same current
most are 200ma bat85
Analog Circuit Design :: 10.02.2010 19:58 :: VSMVDD :: Replies: 18 :: Views: 1472
Choosing VREF may be driven by your desired output voltage.
To get an output voltage lower than VREF requires additional
components (gain amplifier) which adds error and lag. Older
PWMs used zener references which are no good below about
5V. Later came bandgaps and now you see divided-bandgap
references to (...)
Power Electronics :: 16.02.2012 10:58 :: dick_freebird :: Replies: 6 :: Views: 1709
If you use some large resistors to generate the reference then you need a capacitor to keep the noise off it and prevent problems as the comparator switches.
I don't know how you are going to use a zener for 0.3V reference, other than a higher voltage and resistors to reduce it. I am not sure a zener is a (...)
Analog Circuit Design :: 10.08.2010 03:38 :: keith1200rs :: Replies: 9 :: Views: 703
after the 24V zener I connected capacitor (for noise reduction) and then normal diode with 1.5K series resistance and then connected parallel 5.1 V zener and also capacitor. so i got 5V at output side.
This is OK.
Electronic Elementary Questions :: 29.08.2011 05:20 :: kak111 :: Replies: 8 :: Views: 531