Ideal Op amp differential in cadence

• May 2, 2004

• #1

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raju

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cadence opamp

Is there an instance like ideal op amp in cadence?

 

• May 2, 2004

• #2

flatulent

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cadence op amp

you can use the voltage controlled voltage source to get any gain with infinite bandwidth. If you want to select the bandwidth you can make a macromodel subcircuit with this as the input then a RC network to make a pole and follow that by another voltage controlled voltage source.

 

• May 3, 2004

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raju

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ideal opamp cadence

Thanks flatulent. In an ideal op amp the voltage at the +ve input and the -ve input will be same. Also there shld be no current flowing into the op amp. Is there anyway to model this?

thanks,
raju

 

• May 3, 2004

• #4

flatulent

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ideal ampop cadence

This ideal voltage controlled voltage source has no input impedance. It just multiplies the voltage between two specified nodes without putting any further load on them. This function has a one line call and the part name begins with E. Look in the help file for more details or in a book on SPICE.

 

• May 3, 2004

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raju

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ideal opamp in cadence

I wanted to build a circuit similar to this in cadence. Is there a way like build this?

thanks[/img]

 

• May 3, 2004

• #6

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raju

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analoglib iopamp

The circuit is[/img]

 

• May 3, 2004

• #7

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ideal op amp

you can write a ideal opamp with AHDL/verilog-A in Cadence by yourself, or you can find it in a AHDL library which provided by cadence.

 

• May 4, 2004

• #8

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raju

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cadence op-amp design

I am looking for in Spectre. Any type of modelling with controlled sources is also ok.

thanks

 

• May 5, 2004

• #9

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labodhibo

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cadence ideal

Raju,
AHDL also works with spectre.
Piao gave you the right suggestion
Labo

 

• May 5, 2004

• #10

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borodenkov

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op amp design in cadence

VCVS instance in Cadence is what you are asking for. Check the manual for its parameters - besides simply multiplying the input voltage on the gain factor it's also possible model input and output resistance, -3dB point etc

 

• Jun 20, 2004

• #11

opamp741

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cadence ideal op amp

Raju,
If u dont hav AHDL license then use 2 ideal voltage controlled voltage source to replace ur opamp.

E1 vinp gnd voutp vc <gain=10000> <-- check exact syntax
E2 gnd vinm vc gnd <gain=10000>

there will not be any i/p current consumtipm..and if u put ur opamp in negative FB confg, both the terminals will be short virtually..

 

• Apr 11, 2009

• #12

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cadence ahdl opamp

Hello, I am searching the same component in CADENCE (ideal opamp). What about the iopamp symbol which belongs to analoglib. Is this the model of an indeal Op Amp in Cadence?

Thank you very much for your answers and help.

 

• Apr 14, 2009

• #13

dineshbabumm

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operational amplifiers in cadence

goldeboy said:

Hello, I am searching the same component in CADENCE (ideal opamp). What about the iopamp symbol which belongs to analoglib. Is this the model of an indeal Op Amp in Cadence?

Thank you very much for your answers and help.

Click to expand...

Better construct your own idea op-amp using VCVS sources.. Refer to previous posts by members here..

 

• Jan 8, 2010

• #14

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Re: Ideal Op amp in cadence

i hope you still on this thread.

i search the opamp component too.
i try to use the [opamp] component from [ahdlLib] but haven't success to simulate it and just result some error.

the circuit:

can you give me some advice?

 

• Nov 4, 2010

• #15

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ASHUTOSH RANE

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Re: Ideal Op amp in cadence

one can go for using VCVS for designing model of opamp

---------- Post added at 12:02 ---------- Previous post was at 12:00 ----------

refer the analog mixed signal design by baker for more reference or brows LTspice schematics on CMOSEDU.com site

 

• Aug 31, 2011

• #16

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Re: cadence ideal op amp

opamp741 said:

Raju,
If u dont hav AHDL license then use 2 ideal voltage controlled voltage source to replace ur opamp.

E1 vinp gnd voutp vc <gain=10000> <-- check exact syntax
E2 gnd vinm vc gnd <gain=10000>

there will not be any i/p current consumtipm..and if u put ur opamp in negative FB confg, both the terminals will be short virtually..

Click to expand...

I have made this configuration, but when I design a voltage follower and put a pulse in the input I dont get anything in the output. Just a stable 0V signal. nothing changes. What's wrong?