1000 Threads found on edaboard.com: Active Biasing
active biasing is often used in rf power amplifiers where emitter or source is grounded. Such amplifiers are usually dissipating heat. To improve temperature stability negative dc feedback is used to keep average collector (drain) current constant. Feedback is usually made with PNP transistor.
RF, Microwave, Antennas and Optics :: 10-14-2003 22:26 :: Borber :: Replies: 6 :: Views: 2705
I am interested in a LNA design for low noise.
I am told to use an active biasing to minimise the noise figure and also have a lower VSWR ratio.
Does anyone have idea what is active biasing and where can I find information on it?
Thanks for the help
Digital communication :: 10-25-2006 10:41 :: rula :: Replies: 0 :: Views: 508
the active biasing , it to use , other active device to bias ur LNA , this decice could be current mirror , current soure band gap reffernce
Analog Circuit Design :: 03-20-2008 16:42 :: khouly :: Replies: 5 :: Views: 797
Hi, everyone. I have a question about what kind of op-amp I should use to design an active biasing for a power transistor.
Basically the I am going to employ a sensing resistor to capture the power supply current from Vcc to transistor. The voltage drop is then compared with a reference voltage by an op-amp. And the op-amp output is connected to
Analog Circuit Design :: 05-21-2009 02:35 :: winglj :: Replies: 10 :: Views: 1679
Im checking out this FET type LNA IC (ATF-54143) that offers two different schemes of implementation (passive biasing and active biasing)
What is the difference between the two?
Is one scheme better than another in terms of providing gain, rf output?
RF, Microwave, Antennas and Optics :: 09-23-2009 08:42 :: robismyname :: Replies: 1 :: Views: 1986
Did you have a look in their web page (Minicircuits) or the data sheets. If you are talking about a Minicircuit active mixer the power is required for the internal amplifier module so current consumption will depend on the model. Passive mixers don't require any biasing.
RF, Microwave, Antennas and Optics :: 07-30-2003 03:42 :: cross :: Replies: 7 :: Views: 2834
There is an IC from infineon for an active bias circuit.
i am not sure that you can use -0.2 v or not.
RF, Microwave, Antennas and Optics :: 06-07-2004 20:05 :: boy :: Replies: 8 :: Views: 1363
Can anyone show me how to setup the simulation in AWR for a BJT frequency multiplier? I am using an active biasing network also.
RF, Microwave, Antennas and Optics :: 02-28-2008 09:56 :: kosolson2005 :: Replies: 3 :: Views: 1288
One of the reasons I am interested about this, is regarding active biasing. I have found some articles, that say that active bias can be difficult to achieved with class AB amplifiers. I have attached a paragraph from an article discussing this.
I have seen different ways to do active bias. One is where we use a (...)
RF, Microwave, Antennas and Optics :: 09-06-2008 12:25 :: tyassin :: Replies: 11 :: Views: 9568
I´d like to design a limiter with pin diodes. When I use two pin diodes (without active biasing) the point at which limitation starts is to low. The limitation begins at 5dbm - I need it at 30 dbm.
How can I solve the problem? Any usefully documents?
nice greeting :)
RF, Microwave, Antennas and Optics :: 09-10-2008 14:43 :: breitfuss :: Replies: 5 :: Views: 1701
try active bias circuit, it is more stable voltage for temperature change.
RF, Microwave, Antennas and Optics :: 01-14-2004 00:40 :: jupitorcuu :: Replies: 6 :: Views: 2550
Suppose in your second stage you have NMOS common-source amp and PMOS current source load. Then your second stage biasing current is mainly controlled by the PMOS current source, and actually Vgs of the NMOS is determined by this current. However if the opamp is used as a feedback amplifier, the common-mode feedback will automatically adjust the Vg
Analog Circuit Design :: 02-11-2005 00:56 :: terryssw :: Replies: 5 :: Views: 1170
i need a famous topolgy for designing an active bias network for an LNA operating at 11.5 Ghz in an LNB ..
i found a one in Gonzales book but i need a good application note about this topology...
Another question....will the noise figure be degraded so much after biasing the transistor with this topolgy ?!
THANKS IN ADVANCE..
RF, Microwave, Antennas and Optics :: 06-25-2005 08:40 :: mmarwan :: Replies: 2 :: Views: 1315
Why do you have to set Baising for a Tube or transistors?
biasing is required for any transistor that is designed to function as an amplifier, not a switch. biasing sets the DC operating conditions, operating region of amplification and AC swing.
What is the Operating Stage for a Tube?
I don't quite
Electronic Elementary Questions :: 08-16-2005 01:43 :: SkyHigh :: Replies: 3 :: Views: 3534
4th edition of Gray and Meyer teaches you basic to advanced biasing circuits. See active current mirrors chapter. I guess, it is chap.4. Hope this helps.
Analog Circuit Design :: 04-21-2006 02:43 :: vrkrao :: Replies: 6 :: Views: 956
bias 1. Any parameter of which the value is set to a predetermined level to establish a threshold or operating point. Although it is common to think of bias currents and bias voltages, other parameters (e.g., capacitance, resistance, illumination, magnetic intensity, etc.) can serve as biases. 2. In a high-fidelity audio system, a circuit in
Electronic Elementary Questions :: 10-01-2006 11:58 :: Miguel Gaspar :: Replies: 4 :: Views: 1396
In electronics every active device, ex. transistors, needs a contant dc current and voltage on it to work properly. Setting this current and voltage level and giving it to the device is called biasing. biasing determines a device's operating point. What i meant by operating point is: for ex. by bias level you can change an (...)
Analog IC Design and Layout :: 03-15-2007 09:53 :: edata :: Replies: 8 :: Views: 1215
for FET mixers
negative gate bias needed in both cases. For active, drain bias and for passive no drain bias.
Passive: lower noise, lower IM, conversion gain very dependent on gate bias so gate bias control very critical
active: higher noise, higher IM, conversion gain less dependent on gate bias so gate bias control not so critical
RF, Microwave, Antennas and Optics :: 10-10-2007 15:42 :: toonafishy :: Replies: 4 :: Views: 1586
active Frequency multiplier would have been more appropriate topic for this query.
As multiplier in analog electronics means mixer .
Can anybody explain in case of HEMT/MESFET which are biased deep in nonlinear region(for multiplier action), how the bias point shifts(or vary) as the circuit experience extreme cold and hot temperatures ?
RF, Microwave, Antennas and Optics :: 04-15-2009 12:14 :: afz23 :: Replies: 2 :: Views: 808
In reference to u r ckt,
M12 and m13 act as pre charge devices which pull either of out- or out+ to vdd (its explained how this happens in CS amp with diode/active load in razavi)
If you use a resistor to do this job, there will b a drop across it so u r output can't reach vdd any time. which is not the case when u use a pmos device.
Analog IC Design and Layout :: 06-30-2009 17:34 :: Blackuni :: Replies: 6 :: Views: 2424
can anybody help me? I design pulsed power amplifier and I need help with biasing TIM8596-15. How can I do temperature compensated active gate bias and how can I set right drain current? Pulse width is 300ns-30us, D.C. max 20% and PRF 3-50kHz
RF, Microwave, Antennas and Optics :: 12-09-2009 08:13 :: Aalda :: Replies: 0 :: Views: 575
You can do this biasing very easy & simple just use the BIASTEE elemet available in Microwave Office (MWO) (Elements => General => Passive => Other => BIASTEE)
Which is just Ideal Bias Tee
& which does not affect the input admittence...
See the attached picture for the setup for your active Capacitance circuit DC biasing...
RF, Microwave, Antennas and Optics :: 05-21-2010 01:52 :: Manjunatha_hv :: Replies: 1 :: Views: 804
I used ac simulation to find my inductance and Q factor..I will recheck the s-p analysis later.
There is another problem....I implemented a cascode active is meeting my specs....Now i have to implement tunability...What do you suggest is d best way...i'm thinking of changing the bias my g
RF, Microwave, Antennas and Optics :: 09-21-2012 22:28 :: mustangyhz :: Replies: 9 :: Views: 2224
Your bias current changes with the supply voltage, this explains why you see a bigger variation with power supply. You should bias your active device with a current source to keep the bias current constant.
Analog IC Design and Layout :: 07-09-2010 14:39 :: JoannesPaulus :: Replies: 7 :: Views: 1531
I was searching if a transistor is linear device or not. A linear device has a linear relationship between current and voltage (Ohm's law). I'm a beginner in this electricity and electronic stuff. So, please keep your reply simple. Thanks.
While searching I found this:
We will operate transistor mainly in 4 regions, namely
Electronic Elementary Questions :: 04-18-2011 18:29 :: PG1995 :: Replies: 6 :: Views: 7455
biasing the transistor meaning setting it in the right position of the amplifier operation region. in bipolar transistor amplifier the bipolar transistor has to be in the active region and is done from the DC setting which nothing but the biasing. the exact point of the setting is the Q point, in order to have maximum amplification we (...)
Electronic Elementary Questions :: 11-25-2012 07:35 :: Junus2012 :: Replies: 2 :: Views: 963
I do not know what is "passive feedback".
active feedback is used as positive feedback in an oscillator or to make very fast Schmitt Trigger switching.
active feedback is also used as negative feedback in a transistor or opamp amplifier to reduce distortion and increase high frequency response.
Electronic Elementary Questions :: 09-20-2014 11:38 :: Audioguru :: Replies: 15 :: Views: 336
I'm trying to design a low noise amplifier with these specifications:
noise figure <1dB
unconditionally stable K>1
I'm using Avago ATF-34143 HEMT as the active device. I'm quite new to this, I've found tons of stuff online about LNAs but very little on how to design an appropriate bias network. Firstly I
RF, Microwave, Antennas and Optics :: 10-06-2014 13:05 :: Reschak :: Replies: 1 :: Views: 252
active Filter Design
Professional Hardware and Electronics Design :: 09-17-2001 03:11 :: Robin Hood :: Replies: 0 :: Views: 2142
I need a book about active circuits.
Please if anybody has a book or a link where i can find it there, tell me about.
There are books for sedra,Huelsman ... but i couldn't find any free on the net.
Professional Hardware and Electronics Design :: 02-21-2002 17:45 :: :: Replies: 0 :: Views: 972
Who has the schematic of active antenna loop through of DVB_C tuner?
Such as THOMSON DCF8716
RF, Microwave, Antennas and Optics :: 06-07-2002 00:12 :: ynhe :: Replies: 0 :: Views: 2645
I am looking for a low noise inverter chip (8pins) to generate the negative voltage for biasing GaAs Fet's gate.
I tried the Maxim and Linear Technology chips. They performed good but they did'nt accomplish with the temperature range requiride.
Does somebody suggest me some other manufacturer?
Thanks in advance
Other Design :: 07-10-2002 21:01 :: nandopg :: Replies: 2 :: Views: 2036
I was looking for information on the DIY construction of probes. I already
noticed another thread on this board that listed this url:
Good stuff :)
Now, while 1 GHz passive is very nice, does anyone know of any sites that
explain the construcion of say an active 2.5 GHz probe? Yes, I know th
Professional Hardware and Electronics Design :: 12-17-2002 17:23 :: gnihgnahgnap :: Replies: 0 :: Views: 1913
I want to conver a 0-10Vdc signal to 0-2.5 Vdc .I do it by two resistor (1%)as a passive voltage divider,Both the linearity is not good and in some region of full range the value of nonlinearity is high.If I use a .01% resistors the problem may be solved but the cost is too high.
I need to know is there an active solution with opamp fo
Professional Hardware and Electronics Design :: 12-28-2002 18:06 :: 7rots51 :: Replies: 3 :: Views: 2407
is anybody out there to provide me w/ some paper w/ respect to design and analysis of active RC biquad filters (e.g. CMOS implementation) and digital biquad filters realization. Should help to judge different types of implementation (analog vs. digital).
tia & br
RF, Microwave, Antennas and Optics :: 01-02-2003 10:20 :: muppettoon :: Replies: 0 :: Views: 1746
I thought "active" was his question here, not the simulation of some patch. Am I missing the point?
Electromagnetic Design and Simulation :: 01-21-2003 09:12 :: loucy :: Replies: 19 :: Views: 5260
Where is the "active topic menu" on Elektroda?
Was it removed?
ASIC Design Methodologies and Tools (Digital) :: 01-14-2003 10:56 :: LLCD :: Replies: 1 :: Views: 1051
What do you mean on "active power divider" ?
RF, Microwave, Antennas and Optics :: 02-02-2003 15:22 :: g579 :: Replies: 3 :: Views: 959
Anyone have infornation about RF transister biasing? Especially, class B,C.
RF, Microwave, Antennas and Optics :: 02-10-2003 00:18 :: boy :: Replies: 4 :: Views: 1866
I suspect you mean to convert from differential to single ended with one op amp. Then elliptic filter and convert back to push pull.
The Nuhertz filters are available for a 20 day free trial. This program can design passive and active filters.
Professional Hardware and Electronics Design :: 03-13-2003 00:23 :: flatulent :: Replies: 4 :: Views: 1783
active is almost as fast as Modelsim and is much easier to use. It also has many features that Modelsim doesn't. It's equal to Modelsim+HDL Designer.
ASIC Design Methodologies and Tools (Digital) :: 03-14-2003 22:55 :: buzkiller :: Replies: 13 :: Views: 2344
Does there anyone has document on active balun design?It's a distributed active balun,which has the form like a distributed amplifier.
RF, Microwave, Antennas and Optics :: 03-16-2003 07:00 :: Needbias :: Replies: 1 :: Views: 1233
I need kit consists from active components + PCB for XxS510PP.
Send me your quatation to PM
Professional Hardware and Electronics Design :: 05-10-2003 07:24 :: Romanp :: Replies: 0 :: Views: 559
Is there a way to detect the presence of an active cell phone? The idea is to detect a switched-on phone where such a device is not permitted.
RF, Microwave, Antennas and Optics :: 10-13-2003 18:14 :: E-design :: Replies: 2 :: Views: 3349
There is a system level thing to keep in mind with mixers. They are more distortion producing than amplifiers and you should block out your system so that they have the minimum signal level that allows your system to function. Usually, you put a bandpass filter in front of it and have only enough RF amplifier gain to set the system noise figure.
RF, Microwave, Antennas and Optics :: 12-11-2003 12:59 :: flatulent :: Replies: 7 :: Views: 1178
Anyone knows how to calculate active filter noise figure?
Analog Circuit Design :: 02-01-2004 23:52 :: dd2001 :: Replies: 3 :: Views: 1721
Anybody knows how to design: active 6Hz Bessel Lowpass filter? 1st order, 2nd order?
Frequency is very low 6Hz.
and thousands of thanks!
Analog Circuit Design :: 02-02-2004 00:59 :: djalli :: Replies: 5 :: Views: 4035
Does anyone knows how to design a biasing voltage reference circuit with enable/disable function in CMOS?
Normal stable biasing reference point are generated from a chain of equal size PMOS loads. How can we improved this with a enable/disable circuitary which is stable in process and temperature variations? :?:
Analog Circuit Design :: 02-18-2004 00:37 :: wylee :: Replies: 6 :: Views: 2165
I am using a bjt for LNA designing .Which biasing network is most suitable to achieve minimum NF and K>1.
RF, Microwave, Antennas and Optics :: 02-26-2004 01:18 :: ahmer saeed :: Replies: 3 :: Views: 919
what is phemt?what is the biasing condition of phemt?Is its biasing condition is same as N channel FET?
pHEMT (pseudomorphic HEMT) is basically a FET with a different epitaxial active layer & doped such that the electron motion is less random.The transconductance of these devices are higher (hence have higher gain) as
RF, Microwave, Antennas and Optics :: 06-17-2004 07:14 :: v4eda :: Replies: 6 :: Views: 2021