Search Engine www.edaboard.com

26 Threads found on edaboard.com: Input Voltage Mixer

Operational Amplifier for a Voltage Summer

Hi, I am trying to design a voltage summer and all of them require an opamp. I am having trouble understanding how the OpAmp can help the summer, especially when the sum of inputs is less than the voltage required to put the input transistors in saturation. I have designed a two stage single ended OpAmp with gain of about (...)

Consistency between pss, hb, qpss et.al.

Hi, In Cadence (spectre) I have created a simple passive, voltage mode mixer with a 50 Ohm port as input and output floating. So simplify, I use a vcvs to decouple port from the mixer input and shunt the port with 50 Ohm for matching. I then drive the LO with an ideal flo=1GHz square wave and set (...)

How to connect an active mixer to a mobile phone.

The opamp has a voltage gain of 68k/47k= 1.45 times which is not much gain. Its output is capacitor-coupled to an attenuator made with a 10k resistor feeding a 1k resistor so its output is 1/11th the level at the output labelled "To Amp". Try connecting the output labelled "To Amp" to the mic input of your phone.

looking for a matrix audio mixer circuit, with ~ 3 channels

An op amp adder circuit comes to mind. make an op amp input for each channel with a control in the feedback on each for gain and then all connect to another op amp with its output as input to a preamp. depending on the voltage available the resistors or slide pots need to be adjusted accordingly. For most preamps a 1V peak to peak (...)

Problem in Double balanced mixer

Hi everyone... I am simulating a double balanced shown below... 88804 I am giving 2Vrms at LO input and 1Vrms(from Capacitor voltage divider) on RF input... And I am getting 516mV DC at output(on Oscilloscope) but I am not able to think...why am I getting such output voltage...?? since output of the mixer sh

need help in design mixer having input output relation with AWR microwave office

hello i have the input voltage versus output current equation as i(t)=I0*e^avi(t) in an element and want to use this element in a circuit to have a mixer but i dont know from where should i start can anybody help me one thing i know is that this elements acts like a diode but there is a difference between a diode equation and this (...)

how to give input to test circuit of basic mixer???

hello everyone, i've been trying to simulate gilbert mixer in cadence 0.18um tech... while creating test circuit, i saw 'balun' is used in ref manuals. But balun is not giving proper differential outputs with some common mode voltage level,instead it is producing two entirely positive and negative signals. Does dis serves our purpose or do i n

pss P1dB simulation not convergent

Hi, I want to simulate mixer chain P1dB by cadence PSS. It is supposed at 5dBm(input P1dB). The whole chain is consisted of mixer, LPF, two stage IF amplifier. The total voltage gain is 23 dB. The problem is when I swept PSS input power up to 0 dBm, it could't converge. Anyone knows how I can make it (...)

Planing power for my audio mixer

Unless the basic mixer electronics uses a bipolar voltage supply and expects an AC input voltage to generate it, 10V AC can be perfectly substituted by 12 V DC from a wall adapter.

Question about mixer input levels

Does it matter if the local oscillator amplitude on a mixer input (about 9Vpp) is greater than than the IF on the other mixer input (about 3Vpp)? It is a diode ring modulator.

About the Conversion Gain of Mixers

Hello all, I have a misgiving about the voltage conversion gain of mixers, That is defined as VIF/VRF, where VIF and VRF are the input and the output voltages of the (downconversion) mixer respectively. My question is- why this definition do not include VLO (the other input of the (...)

Negativ Output Voltage: Gilber Cell

Hi - I have a Gilbert Cell, mixing the signal from 7GHz directly to 0Hz. Now sweeping both phases of the LO input signals coherent, there are constellations where the mixer delivers negativ output voltage. Can the be explained? Greetings, Thomas

How to supress LO second harmonic in Gilbert cell mixer?

I am designing a low voltage(1.8V) Gilbert cell mixer, which includes(from bottom to top) tail current mos, RF input mos, LO switching mos, and resistive load. Since LO has large amplitude, there would be a large common-mode second harmonic of LO at the drain of RF input mos, which may cause the RF input mos (...)

current-mode passive mixer problem

I am designing a current-mode passive mixer which consists of gm,mixer core and tia stages. The mixer core is ac coupled to the first stage. I wonder about the input offset voltage of tia, is it feedback by the resistor or other ways? I tried to use the feedback resister. The input and (...)

help with proper noise source in Cadence

Hello All I am simulating a mixer in cadence and for measuring its NF I am using PSS+PNOISE. in Pnoise setting, for setting input and output we have options of voltage source and probe for output. The former option takes into account the noise added by port's internal resistor itself while the latter does not. The results differ by (...)

Questions about LO power/conversion gain and stacked transistors in gilbert mixer

For the second effect the reason is as following: If you take a look at the common emitter voltage of the switching pair it will behave as a rectifier regarding the input LO voltage. It has harmonics two times the LO. Because the switching pair is driven on some IF current source ther exist also some parasitic capacitance from this IF (...)

how to simulate a current mode mixer?

I believe that LO power is making the mixer in current mode I agree that input and output are voltage / power mode. This is because of 50 ohm impedance for both input and out put side. If you do not folow the same impedances then I guess it called as current mode.

LNA+lowIF mixer sim(PSS+PAC)&(PSS+PXF), strange voltgain

Dear all, I design a LNA + low IF mixer. I have combined them and do the voltage gain simulation using spectreRF. I use PSS + PAC to get the voltage gain result. However, it gives out a strange result. Actually, I need to set the RF input port PAC Magnitude in a certain value for simulation. If I give different magnitude, (...)

Dual up conversion mixer simulation problem

Dear all, I am doing dual up conversion mixer simulation using SpectreRF simulator. However, I do not know the setting of NF and voltage gain simulation. I hope you could give me a step for reference. My simulation input is as follow: RF input: DC with a band from 0 ~ 250MHz (the RF input (...)

How to define the output impedance for LNA simulation ?

Due to mixers are very nonlinear components, input impedance of a mixer can not be defined precisely.Therefore we "can" assume the mixer input impedance "matched to 50 Ohm" ( in fact it's not true..) but there is no way out this.. For LNA, NF is not affected by output impedance but input (...)