# Search results

1. ### Hspice waveform problem

Hello all, I simulated a circuit in HSpice 2008. The problem is that the output waveform is not accurate and is segmented. Please see the attached picture. I used smaller step in .tran analysis, but it does not correct: .tran 1n 2u This problem does not exist in Hspice 2003.
2. ### Monte Carlo simulation for W/L+variaition oercent

I want to do Monte Carlo simulation with Gaussian distribution for W/L (width/length) in HSPICE in 0.35um CMOS technology. How much variation percent should I consider ? and why?
3. ### Total Gm of OTA versus Frequency

How can I plot the total Gm of OTA circuit versus Frequency in HSPICE?
4. ### slew rate of OTA circuit

I am simulating a trans-conductance circuit (OTA). I want to obtain pulse response of the circuit. So I applied a square waveform voltage as the input, then I see the output current. My question is that may I compare the output current waveform with input voltage and then calculate the slew...
5. ### output current of differential pair (Transconductor)

Hello every one I want to calculate output current of differential pair circuit which is used as a OTA, but I could not obtain. I attached the related paper which claims From eq. (2)-(4) we can obtain the output current of eq. (5), unfortunately I could not obtain the result which they...

Hi every body, I need a simple analog circuit consist of only MOS transistors to do this: Vo=(V1+V2)/2 Where V1 and V2 are DC voltages less than 1v. By the way the V2 can be negative e.g. the circuit should be work for (V1-V2)/2. If you have idea by using resistors it works for me. I can...
7. ### How does this circuit work?

I studied a paper attached with this post . I have a question about Fig. 3 which is also attached where a topology to realize multiplier circuit has been presented: How can we apply "iin1" to "EOTA1"? In the paper it is mentioned that "gmT1" has a direct proportion to "IBE1", when we change...
8. ### [SOLVED] transconductance measuring in the OTA simulation

How can I measure transconductance (gm) of a OTA ? or how may I draw transconductance of OTA in terms of input voltage variation? I want to divide the input voltage difference signal by output current, but it doesn't allow because when vin=0, the gm is infinite !!
9. ### CMOS OTA with low gm

Hi every body, I designed a new CMOS OTA which has high linearity as a voltage-to-current convertor. Also I utilized a technique in which "Iabc" has a direct proportion to "gm", i.e : Iabc=Kgm, where K consists of W/L of input transistors and some other constant parameters. By the way all of...
10. ### gm/Id analog design source

Hi I want to study on the subject of "gm/Id design". Do you know good source or book. I found this useful book: the gm/id methodology a sizing tool for low-voltage analog cmos circuits Does anyone have this book and share with me ?
11. ### propagation delay for the ANALOG circuit

Hi, I have designed an analog circuit, then I applied a square pulse to the input and get the response at the output. For the sake of speed examination, I measured the propagation delay for the output (low to high & high to low delay). Is it right to measure the propagation delay for the...
12. ### power supply vs. technology

Hello all, Is it typical to simulate a circuit with the CMOS technology of 0.18um with the power supply of 2.5? or it should be 0.25um or 1.8V? regards,
13. ### power supply noise in HSPICE

I want to test an analog circuit against power supply noise in HSPICE. How can I apply noise signal to VDD? (Which command, or example)
14. ### export high quality picture from HSPICE

Hi every body, I am using Hspice simulator. I need high quality picture from the simulations. How can I export that? And may I use MATLAB to draw the results from .lis file? How?
15. ### [SOLVED] negative percentage of error

Dear all, I want to show the accuracy of a circuit against process variation by histogram, where zero is putted on the middle of that. Therefore negative and positive percentage of error are defined. Negative (positive) sign for the errors which are smaller (larger) than ideal output...
16. ### complementary of the analog signal (symbol)

Hello every one, I have a question about a symbol. We know that, complementary of a digital signal is shown by bar on that signal. How about an analog signal. Suppose that we have a reference current of Iref, the output current is Iout=out1. Now we would like to have Iref-Iout. How can we...