Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
I need to do some gain measurements of my MESFET amplifier at around 4 Kelvin. To measure the temperature I was hoping to buy Silicon diodes from Lakeshore - just realized that they are very expensive ($500 bucks for the calibrated ones). Is there a way i can rig up something in the lab...
cadence transient noise
Section 2-23 of the PSpice A/D Schematics Version User's Guide describes very nicely witha n example how to do the noise analysis.
You can access the manuals clicking on help-> manuals in the Top menu of the Capture-CIS.
I have to design a preamp using GaAs FETs which will sit in a very strong magnetic field 14 Tesla. The magnetic field (B) if at an angle to the channel will exert a force to the flow of charge carriers from Drain to source. To avoid this I plan to align the FET channel in the direction of the...
I want to try the folded cascode. I read few things about folded cascode however, it is still not clear how it wld isolate the input capacitance in BW determination - for my TIA.
Please if you have a reference to any article/books.
PS: My signal frequencies of interest are 10 KHz -...
I am designing a transimpedance amplifier which needs to amplify around 100pA of current to few mVs , the signal frequency is from 10Khz to 10 Mhz. I start with a 1M ohm resistor to convert this current into voltage and use a FET in a source follower configuration for pre-amplification.
thanks guys very useful information for me.
Though, one more question, i found these Channel protector lying in my lab.
Can i use these in series with my signal wires? The good thing is in one package i can have 8 channels protected...
I have an Analog output card which is generating +/- 10 volt, and drives a metal plate in my instrument. This metal plate which is basically a load capacitor of around 20 pF, can sometimes have transient voltage from pick up. I want to protect my AO signal channels from these high...
Re: Urgent help
I have connected the battery in parallel with a regulated dc power supply i have. The bike manual says that to keep the charging rate 1.1A X 10hrs. So i have limited the current from my power supply to 1.1 Amps. Though the voltage is only 12.6 volts.
If i want to...
Re: reduce the noise
Besides using circuit design techniques for low noise application such as source impedance matching, you can reduce thermal noise in the preamps by cooling the circuit itself. People have used dry ice and also liquid helium to aprox. 4 K. But then you have to select the...
differential amplifier question
I am making a differntial amplifier, and the circuit i am trying is attached as a Pdf. In my simulations when i probe the voltage at the collector of Q1 and Q3 i see they are in phase. If i remove the second stage (AD797) they are fine in quadrature with each...
thanks for your comments.
I did my measurements of current as i told you. Now, i want to calculate the dc and the ac current in emiitter, collector and base of BUH51. Is there a way to estimate it analytically, to justify the trace widths on the PCB?
Sorry for being a real pain guys. Still i don't get one thing.
Ok, let me tell you how i am trying to bias the design.
Just take resistor values to be Rd1 and Rd2.
I want the Q3 and Q4 to be biased at VGS = -0.6 and VDS = 3.5 volts. (IDS ~ 10 mAmps for these bias values)
Thanks a lot Borber,
I did my dc current measurements at the 215 volt supply. For Output voltage 400 p-p at the secondary of the transformer, i measured the DC current drawn is around 113 mA. So the power dissipation comes out to be 6 watts/ transistor.
I might sometime use 1000 volts p-p...