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Topic: DSO op-amp replacement? OPA2681 -> OPA2691? (Read 253 times) previous topic - next topic

DSO op-amp replacement? OPA2681 -> OPA2691?

Jer made the schematic for the DSO. I've been reading all the datasheets today. TI says the OPA2691 is exact equivalent of the 2681 and recommends it.

http://focus.ti.com/docs/prod/folders/p ... a2681.html
http://focus.ti.com/docs/prod/folders/p ... a2691.html

Does that look ok to you? It looks a slightly better in some limits, but most specs seem the same.
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Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #1
Looks ok to me.
"Too many projects, so little time"

Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #2
BTW I will have some of the ADG5436 on Monday.
"Too many projects, so little time"

Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #3
I just ordered buffers and MSP430s for some other projects, I should have picked up the ADS831...
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Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #4
Here's the first cct and pcb. We're going to flatten out the power supply a little to make it thinner. Right now it's about as wide as the sniffer.
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Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #5
Note that some of the pin connections changed to be more direct routes to the ADC.
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Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #6
Here's the v2 update, I'll probably send this to the board house if you don't find issues in your tests.
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Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #7
Are the design files checked in anywhere? I'd like to start doing a cost analysis.

Jack

Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #8
No, not yet. I don't have a version with the relay update. There should be a BOM pdf and xls in the DSO_WING_v03 design package McZ PM'd the link for.
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Re: DSO op-amp replacement? OPA2681 -> OPA2691?

Reply #9
Actually, I recall McZ did a full cost-out, it's in the .zip.
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