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This is quite wideband and cascade connections may not give this bandwidth and power level. Instead of that, "distributed amplifier configuration" should be used. For this kind of amplifiers, there are lots of document and paper. But it's quite difficult to implement.

## How to resolve or reduce the bandwidth shrinkage?

Hi everyone. Need some advice from you all. Basically when we cascade amplifiers we faced the problem of bandwidth shrinkage. Is there any way where i can resolve or at least reduce the bandwidth shrinkage. From the text books for example Franco and such we can find numerous formulas to have the widest bandwidth however (...)

## bandwidth drop with cascaded limiting amplifier

my opinion is when a few limiting amplifier cascade together, the gain will increase from first stage to the last stage. As gain increase, the miller capacitance also increase according to formula cgd(1+A). This will form a even lower frequency pole as incresing stages, f=/2pi. RC. The output of the last stage will be the dominant pole or the firs

## Delta-Sigma 2-2 cascade topology design technique?

Deal all, I will design 14bit/24MHz sampling 2-2 cascade delta-sigma ADC,Where I should to be careful design rule?stability?or power consumption? About OTA design, How do many unity-bandwidth and settling time enough to satisfy? Design spec: resulation: 14bit input bandwidth: 1MHz Sampling speed: 24MHz OSR=12 Thanks a lot.

## A problem of cascade of inverter driver!

Hi all i am designing a driver using cascade of inverters to drive a large capcitance (20pf)! But the delay is too large beyond our requirements. The delay should be less than 4.5ns. the power is 1.5v and i use the p35(n35) MOSFET. So any other method to do the same thing? i use the UMC0.25u. i want to know if the p25(n

## bandwidth of amplifiers in cascade

if there are n stages of amplification each with bandwidth = b what is the effective b.w of all n amplifiers in cascade?........ i found it as b.(2^1/n -1 )^.5......how?

very oftenly i was messed up by this question....how to find the differences between Cascode and cascade amplifier... LIST out some prons and cons of cascade and Cascode amplifier

they are not cascade or parallel in fact they are independent & we need to find a separate analysis of their bandwidth thankyou......

## Dimension a Cascade connected circuit

Hello, before I ask you my question I just wanted to say I am new at the board. So over to my question. I need some help to dimension a cascade circuit amplifier with the LM324. The circuit must fulfil the following values: - In Impedance = 25kΩ - Above frequency = 100Hz - Below frequency = 150kHz - Maximun gain = 40dB I have solve

## Confused..why this cascade diff amp output distorts????

middle stage final output images.el

## Increasing bandwidth 2 stage opamp cmos

Hi I can not see how large is your bandwidth. I have designed fully diff 2 stages op amp 1.8v has 500Mhz bandwidth. 61db gain and 64 degree phase margin. I use standard 2 stage op amp (no cascade). I think you can improve your bandwidth from 800Mhz to 1ghz

## how to determines bandwidth of Microwave components

Hi, Is there anyway to do manual analysis of, say a quadrature hybrid to determine its bandwidth (as I was able to do in low frequency cmos circuits)? While discussing quadrature hybrid, Pozar writes " ... the bandwidth of a branch-line hybrid can be increased to a decade or more by using mutiple sections in cascade". Any analytical (...)

## RF Microwave Tools - part 47 ( RF System Calculator )

RF System Calculator This is a excel spreadsheet that analyzes cascaded stages in Receivers and Transmitters. The cascade analysis includes Noise Figure, Gain, intercept point, power input/output, SNR (in a given bandwidth), etc. A main signal can be present as well as a pair of interfering signals for analyzing off-channel IM3 rejection (...)

## HELP ME!: how to design 1.57Ghz Microstrip antenna for GPS

It is hard to make an antenna with this limited bandwidth. The better thing to do is to use an antenna with modelate bandwidth and then cascade it with a good bandpass filter. This will be better. Search for patch antenna structures. There are a lot of examples available

## How to determine transistor size of folded cascode ota?

hi, If the ID and gm are fixed, how to determine transistor size and bias voltage of cascade output stage. thanks! Rose

## Using high frequency probes for spectrum analyzer

high frequency probe is one high impedance voltage is designed for minimal influence to the circuit with a moderate bandwidth.If used with VNA,it will be very convenience to check cascade chain problem without disconnect the chain.

## need help in wide band opamp design

Well, the 110 dB gain, if at dc, is no problem. However, the 1 nF cap load will always make your ampflifier act as an integrator. If your target is high gain at high frequency, you have to use some inductors, and that will make it narrow-band. If your target is high Gain-bandwidth product, then you may try cascade. However, watch out the phase m

## What is the two stage cmos opamp ?

A 2 stage CMOS opamp is a operational amplifier which is made up of 2 amplifying stages in cascade. 2 stages are generally used to achieve high voltage gain and high output swing simultaneously, 1 stage is optimized for each parameter. You can have more stages in cascade to acheieve higher gain, but at the expense of reduced bandwidth. (...)

## Bandpass Filter problem with filtering frequency

When designing band pass filter you must satisfy few criteries. First you must define 3dB pass band or ripple. Second, bandwidth where you define wanted attenuation. Third, chose filter type Butterworth, Chebyshew etc. Filter in your case 1k-8k can be passive or active what is easier to realize. Better design approach is to design low pass and h

## Whats the difference between active and passive filters?

Hi ! We use op amps in active filters because we can simulate the characteristics of RLC elements used in passive filters, using only resistors and capacitors and not inductors (no one kind of active filter uses inductor). More advantages are that we can give a gain to the stage (we can cascade several stages to increase and sharp the slope of

## How to design digital ajustable FIR filter?

Hi, 1. The easiest solution (however expensive) is to design many filters and choose one of them depending on the bandwidth. 1a. If you are using an FPGA, there is no wastage of resources so you may load 6MHz filter instead of 4MHz filter 2. Try to find a cascaded filter structure and you may use only the required number of stages. hope

## Design a digital narrow band bandpass with lilttle taps ?

Hi I am not sure, but may help you. If sharpness of the filter is not important for you, design a FIR HPF and LPF filter with cutt of frquencies about your requested BPF center frquency and cascade them. Regards

## Is mixer a passive device when calculating noise figure?

Use the classical cascade calculation algebra and use the noise figure and gain as numbers (not dB). This formula works for all passive and active stages. Passive stages have the noise F as the loss value. A 3 dB resistive attenuator has a gain of -3 dB and a noise figure of 3 dB. Diode ring mixers usually have a noise figure that is 2 dB worse

## How to have 2 LNAs before a mixer in RF front-end design?

You didn’t specify that this is an RFIC design. So, in a standard RF circuit design you need a proper match between two cascaded LNA’s to get the required Gain, Stability, bandwidth and Noise. The matching impedance between two cascaded LNA’s could be different than 50 ohms, from the moment that is not interfaced with (...)

## How to do using the MatLab to simulate Delta-Sigma SNR ?

Hello, How to do using the MatLab tools to Simulate Delta-Sigma SNR performance? If Delta-Sigma spec fllow : 1.cascade 2-1 Delta-Sigma ADC 2.Supply=3.3v OSR=64 Maximum Input Signal= 1V peak-peak input signal bandwidth= 500KHz~5MEGHz Sampling rate= 200MEGHz Dynamic Range= 90dB SNR= 75dB For OTA Design, How ma

## How can I make matching with Lumped elements at 100MHz??

You can use a cascade of LC structures to improve the bandwidth of your matching. I usually don't use the ADS Smith Chart tool to match, but I do the S parameter simulation to match a load. You can use the optimizator also. By

## Isolation problems in multistage wilkinson power divider

Hello I'm now designing a 5 stages 'cascade' Wilkinson power divider (bandwidth 0.5GHz -6.5 GHz) on RF-60A (Er=6.15, H=1.542mm)according to "A general design formula of multi-section power divider based on singly terminated filter design theory". With the value I calculated according to the specifications in my case, I can have exactly the

## Is downsampling a better option??????

Hi everyone.I am sampling at 8000.This is the min sampling rate possible.I cant sample at rate lower than this in dsp tms320c6713.I want to implement a bandpass and a notch filter in cascade.If i change the sampling rate to 300 using decimation and interpolation i would be able to reduce the computations required. But on the other hand interpola

## help me in design circuit

please show me the circuit of "Two decade BJT-OP AMP cascade inverting voltage amplifier". SPECIFICATION: only one BJT,One OP AMP UA 741 and a single power supply of 12v must be used. a 10K ohm load and an input signal will be connected via capacitors to the amplifier.The maximum voltage gain is about -500. Input impedance is about 600 oh

## Do you think that the slow input clock may affect my lock detection counter?

Hi Crazy_analog If your input frequency is such a low frequency, then your lock is ridiculous. If under your application, if u really need to use that, I prefer you add a cascade of frequency doubler to increase the reference frequency to increase the lock time.

## bandpass switched capacitor filter design question

HI,guys, I am a new comer for help. I am working on designing a bandpass SC filter. The specification are as follows: center frequency is 120K; passband 10K-15K(the bandwidth), passband gain 0-3dB;stopband 70K-80K(the bandwidth), and stopband attenuation >-60dB; I designed this filter totally according to the chapter 9 of Allen's book

## Question about system noise figure calculation when every block noise figure is known

If the noise figure of each block in the receiver is known, we can calculate the total noise figure of the system with the cascade noise figure formula. The calculation is based on the condition that all the blocks are matched to 50 Ohm. But this is not the fact! So the calulated result should be no sense. Any comment on my viewpoint?

## Help me design a 4 stage cascaded amplifier

hi , I got problem want ask all of you I 'm design a limiting amplifier that need 4 stages which is cascaded ,each stage is a differential pair . When i design each each stage to satisfy its gain and bandwidth i must choose common mode input also .But when all of stages are cascade ,the output common mode voltage of a stage will be (...)

## why my amplifier is oscillating?

I cascade two stages of UPC2776 as a post amplifier to boost the signal from a Transimpedance amplifier. Since UPC2776 have 23dB gain and 2.7GHz bandwidth and TIA supposed to work at 70MHz, it should not be problem from bandwidth point of view. The wired thing happened once I power up UPC 2776. Output of the second stage oscillating (...)

## Band Pass Filter design

HI all, Can I design a Band Pass Filter Using cascade connection of LPF and HPF for a BW of 270K?(narrow BPF)

## Need Circuit Using BJT and

anybody can help me to find circuit that has TWO DECADE BJT-OP AMP cascade INVERTING VOLTAGE AMPLIFIER please help me as soon possible attach the circuit or any suggsestion to me..thanks title: Two decade BJT-OP AMP cascade inverting voltage amplifier SPECIFICATION: only one BJT,One OP AMP UA 741 and a single power supply of

## comparison of two LDO structures !!

A is better. For B: If load current = 0 than output transistor gate-sorce voltage is near threshold. In this case diff cascade works bad because right transistor is in saturation.

## Ultra-wideband filter design (need help)

is there any other method beside cascade highpass and lowpass?

## npn cascode amplifier for good IP3 - rule of thumb

I?m looking at a design using a NPN cascade amplifier for good IP3. I read on internet that there is a rule of thumb in Sedra & Smith near page 536 that states, ?1/4, 1/4, 1/4, 1/4 biasing rule to set up bias resistors?. My copy of Sedra & Smith is dated. Does anyone have knowledge of this rule of thumb? I?m trying to decide how much Re and Vce

aibrahim, You can calculate the effective bandwidth of any number of cascaded sections by doing the following: Make the substitution s=jw in the transfer function for each section to get the frequency domain response. . Multiply the frequency domain responses to get the overall frequency response. . Calculate the frequenciesy at which the nor

## bandpass filter 600-1000MHz

Lumped element method is the best solution. Use a high pass in cascade with a low pass to realize this band pass filter. Good luck!

## design of ASIC CMOS opamp

Don’t use a two stage approach; you will burn too much current in the second stage. Unity Gain bandwidth = 500 MHz => for stability second pole should be around 1.5 GHz!!!!! Second Pole = gm(second stage)/(2*pi*Cload), believe me that will cost current. Normally a folded cascade should be enough to reach 75 dB, but probably not with that

## OpAmp design - estimation of unity gain

The story of dimensioning the max bandwidth of an opamp is much easier if you start from the end. The opamp could not have more bandwidth than the output stage. The Gm/Cload of the output stage define the parasitic pole which could not be compensated or avoided. If the phase of the ouput stage reach -30° the unity gain of the opamp and the feedb

## Total Power Radiometer - help with simulations needed

Nothing is easier. In other words: ask Yourself what really need. E.g. the total power radiometer do not require a sophisticate simulator. A very simple, cascade simulator, wrote in MS Excel is often enough. One of the key is the input power. The out voltage is: Vout = K(Tobs+Te)B G Gamma K : Boltzman

## multiple order passive RC filter

Would I just cascade the RCs? Rgds, IanP :D

## How to implement a delay unit in a delta sigma modulator design?

Hello, I want to design 2-2 cascade delta sigma modulator for 2 mhz signal bandwidth, i must sum the two outputs given by the two stages, i use ORCAD PSPICE for similation, i need to implement H(z) =z^-1 which is a delay unit, i don't know the structure of this function using MOS transistors and how i implement it. Please help me

## how to improve P1dB of LNA?

Friends, I am designing a GaAs LNA. Tech is WIN (Wireless Information Networking) 0.5um INGaAs pHEMT Enhancement/Depletion-Mode Device. The LNA requires variable gain from 0dB~18dB, P1dBin >-10dBm@18dB, 0dBm@0dB. And working frequency between 400MHz---900MHz. I tried many kinds of circuit, such as cascade with feedback (single stage), common so

## What's the output jitter performance after several cascaded PLL?

Hi, you wrote >>> I know that the PLL can filter the low frequence noise itself,so the low frequence jitter of output maybe better than input. I think a PLL will filter high frequent input noise. The low frequent input is tracked. regarding your question. I think if you cascade multiple identical PLLs you will run into issues. At least i

## Low Pass Sallen Key Filter design

At this frequency you can use gm_c filter. Designing at such frequency might be difficult with active rc filter or switched capacitor filter. But the linearity if gm-c filters is inferior compared to the other ones. Conventionally, you design it with a cascade of two bi-QUAD stages

## Gain reduction techniques

Source degeneration is pretty consistent. A cascade of low gain stages can perform better than a smaller number of high gain stages when it comes to bandwidth and low- overdrive prop delay.