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Recommend Opamp for integrator in audio oscillator

Question asked by diffuse371 on Jun 27, 2014
Latest reply on Jul 3, 2014 by iamPhil

Hello, I am designing a 20hz to 20,000hz oscillator based on an implementation of a state variable sin and cosine generator.

 

Selection for opamp integrators has me scratching me head.

 

I'm currently torn between the AD744 and the AD845 . Budget constraints are placed a decent distance behind perfectionism.

 

The decompensated 744 has good speed which the perfectionist in me believes will translate to good sonics. All other specs seem good, though perhaps the 711 would be a safer choice.

 

The 845 seems to come recommended in the datasheet for this purpose, with what seems like a better output stage, although bias current is much higher.

 

Can any engineers help me with this choice? Any characteristics that I have neglected to observe (perhaps concerning phase response), or another (DIP) opamp to recommend? Or perhaps some recommended reading?

 

Many thanks in advance for any input.

 

Mark

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