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What factors should be considered when choosing an op-amp?

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faraday_3

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What factors should be considered when choosing an op-amp?
 

ceaser

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Re: Op-Amp Selection

i think the main factor is the slowrate which define the max freq. to be used in the
operation

also gain bandwidth product which define the gain at diffrent conditions of applied
signal freq
 

Davood Amerion

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Op-Amp Selection

it is compeletly depend on it's application.
 

zhancangF117

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Op-Amp Selection

most on its application and structure
Slew rate
bandwidth
 

Chethan

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Re: Op-Amp Selection

selection of opamps depend on ur application..
some applications such as BGR require ur opamp to have high gain...
some applications require higher slew rates and faster switching times.....
so the main parameters can be.
SR
Gain
BW
 

Miguel Gaspar

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Op-Amp Selection

First you must understand the kind of electronic system you want to design, ans that will define the king of op-amp. Because there are so many kind of opamps you can consult the classification of op -amp the first of them:

input output
Voltage Voltage
Voltage Current
Current Voltage
Current Current

The first one is the most common and there are so many kinds of the: general purpouse, high speed, high SR, precision, low power, etc.
 

test_out

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Op-Amp Selection

I think it ups to your application. ex, if you u the Op-Amp for comparator you have to notice about the speed.
 

collinjie

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Re: Op-Amp Selection

The input voltage range should be considered too.
 

pillar_chen

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Op-Amp Selection

The input/output range, slew rate, bandwidth, offset,gain.
 

Kral

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Re: Op-Amp Selection

faraday_3,
Op-Amp parameters fall into 2 categories:
DC parameters (Affect errors regardless of frequency)
Input Offset Voltage
Input Offset Current
Input Bias Current
Common mode rejection Ratio (CMRR)
Power Supply Rejection Ratio
Differential Input Voltage Range
Common Mode Input Voltage Range
AC Parameters (Affect errors at high frequencies)
Slew Rate
Gain-Bandwidth Product
Regards,
Kral
 

manissri

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Re: Op-Amp Selection

The opamp selection depends upon ur applicaation.
whether u r using it for dc operation r transient operation,
for dc operation the gain should be high and for transient applications the speed wil be the main criteria so u need to focus on bandwidth of opamp.
hope this helps.
manissri
 

graikos

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Re: Op-Amp Selection

bandwidth
Power Supply Rejection Ratio
Voltage Current
Current Voltage
Current Current
 

jinxingsun

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Op-Amp Selection

The selection of a op amp is up to your application,such as high speed?low noise?low distortion?larger output swing?
 

Sigma|Six

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Op-Amp Selection

I have a quick question in op amp selection as well, when do we consider CMRR?

What is the pratical problem will exist if I select an op amp with wrong CMRR specs.

Is there any CMRR discussion in the forum before?
Can you send me the link?
 

srinivasan

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Re: Op-Amp Selection

plzz Put your specifications
 

aandy

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Op-Amp Selection

Input Impedance, is another criteria I blieve ..
 

maharshi_qis

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Re: Op-Amp Selection

1.slew rate
2.phase margin
3.ICMR
3.Gain
5.CMRR and PSRR
6.offset


these are the most critical parameters for op-amp in general.
 

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