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TINA/Spice/OPA2189: OPA2189 BPF design

Prodigy 230 points

Replies: 35

Views: 2172

Part Number: OPA2189

Tool/software: TINA-TI or Spice Models

Hi Sir,

The following are BPF requirements and please provide TINA simulation. Thank you.

1. 25KHz BPF

-opamp power supply 5/-5V or +15/-15V

-input 5V 25KHz square wave

-BPF BW: 1KHz 

-filter order: 8

-ripple: 1dB

-stopband attenuation: -35dB at least

-25KHz phase: 0 degree

2. 60Hz BPF

-opamp power supply 5/-5V or +20/-20V

-input 5V 60Hz square wave

-BPF BW: 20Hz 

-filter order: 8

-ripple: 1dB

-stopband attenuation: -35dB at least

-60Hz phase: 0 degree

  • In reply to Michael Steffes:

    Oh and one more comment here on the RC tolerances.

    Most of these filters seem to have the Fo set by RC product type terms. If you limit yourself to best case 1% C0G gaps and start out using 0.5% R's that seem pretty low cost you will have some Fo spread. Since the 1% C's kind of dominate that spread, it seems diminishing returns to commit to the big step up in price for 0.1% R's.

    Michael Steffes

  • In reply to Michael Steffes:

    And, Tom pointed me to the perfect part for this - the OPA1678 dual audio amp, updated at bottom of word file with its TINA file

    25kHz 4th order BP suggestions updated AM filter.docx

    AcerbergMossbert BP with OPA1678 25kHz redesign 4th order.TSC

    Michael Steffes

  • In reply to kai klaas69:

    Thank you, Kai

  • In reply to Michael Steffes:

    Hi sir,

    I run your design(OPA1678) in TINA-TI, AC transfer is okay, but transient result have some problem as attached file. 

    Can you help to check it?

  • In reply to Michael Steffes:

    Hi Michael,

    AcerbergMossbert BP with RC4558 25kHz redesign 4th order.TSC can be download, but can't open by TINA. Can you send it again? Thanks!
  • In reply to Tseng Roger:

    I also have a lot of problems running transient, get kind of random results depending on time length, not sure - the V7 version of the RC4558 is attached 4213.AcerbergMossbert BP with RC4558 25kHz redesign 4th order.TSC

    Michael Steffes

  • In reply to Michael Steffes:

    Morning all,

    Well, as I said at one point I normally only get LP filter questions and virtually no BP questions - so it was time to explore this DABP approach.Wow, how cool and simple is this? It can't generate more than a 2V/V peak gain, but otherwise seems pretty simple and powerful. One thing to keep in mind is these designs generate exact RC at first, and then you need to step them off to E96 R's and E24 C's - that always give a shift in the nominal response from your design goal - then you apply tolerances on those for spread.

    Here I assembled the targets 2 stages for your design Tsing and looked at it in detail - OPA1678 implementation attached as well - So only 2 duals now and looks as good as the Akerberg Mossberg - that one can generate easily tuned wide range of peak gains though.

    4th order BP using the DABP topology.docx

    4th order DABP with OPA1678.TSC

    Michael Steffes

  • In reply to Michael Steffes:

    Hi Michael,

    here are my results of your last simulation. (I replaced the current source by a voltage source, for clarity, and added a measuring point to the output):

    tseng1.TSC

    Kai

  • In reply to kai klaas69:

    Yes Kai, these are what I see also - I probably attached the last sim I did testing the input impedance, these look pretty good don't they?

    Michael Steffes

  • In reply to Michael Steffes:

    Hello Tseng,

    I hope the collective responses from Kai, Michael and myself provide sufficient information for you to apply the DAPB filter effectively in your application. If so, please go ahead and close this e2e inquiry.

    Regards, Thomas

    Precision Amplifiers Applications Engineering

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