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What's so special about these op amps?

B

Bob Engelhardt

Jan 1, 1970
0
I found these devices at the "swap shop" at our dump; not having any
idea of what they were. I Googled them and found this:
http://www.intersil.com/content/dam/Intersil/documents/fn29/fn2902.pdf

Summary:
• Bandwidth 12MHz
• Input Impedance 500MΩ
• Input Bias Current 1nA
• Input Offset Current 1nA
• Input Offset Voltage 0.5mV
• Gain 150kV/V
• Slew Rate 7V/µs

The data sheet has a 2006 date & there weren't many sites offering them,
but a couple that did had prices up to $43! Each! WTF? What makes
these so dear? (It's probably obvious, but not to me, if so please
excuse my newbie-ness.)

Bob
 
T

Tim Williams

Jan 1, 1970
0
2902, isn't that a variation on the LM358 (158/258/...)?

Price doesn't mean much, could be scalpers trying to scam people on
availability.

Tim

--
Deep Friar: a very philosophical monk.
Website: http://seventransistorlabs.com

I found these devices at the "swap shop" at our dump; not having any
idea of what they were. I Googled them and found this:
http://www.intersil.com/content/dam/Intersil/documents/fn29/fn2902.pdf

Summary:
• Bandwidth 12MHz
• Input Impedance 500MΩ
• Input Bias Current 1nA
• Input Offset Current 1nA
• Input Offset Voltage 0.5mV
• Gain 150kV/V
• Slew Rate 7V/µs

The data sheet has a 2006 date & there weren't many sites offering them,
but a couple that did had prices up to $43! Each! WTF? What makes
these so dear? (It's probably obvious, but not to me, if so please
excuse my newbie-ness.)

Bob
 
I found these devices at the "swap shop" at our dump; not having any

idea of what they were. I Googled them and found this:

http://www.intersil.com/content/dam/Intersil/documents/fn29/fn2902.pdf



Summary:

• Bandwidth 12MHz

• Input Impedance 500MΩ

• Input Bias Current 1nA

• Input Offset Current 1nA

• Input Offset Voltage 0.5mV

• Gain 150kV/V

• Slew Rate 7V/µs



The data sheet has a 2006 date & there weren't many sites offering them,

but a couple that did had prices up to $43! Each! WTF? What makes

these so dear? (It's probably obvious, but not to me, if so please

excuse my newbie-ness.)

There MIL-SPEC parts so the price is jacked through the roof. Now you know why the government is broke.
 
J

Joerg

Jan 1, 1970
0
Bob said:
I found these devices at the "swap shop" at our dump; not having any
idea of what they were. I Googled them and found this:
http://www.intersil.com/content/dam/Intersil/documents/fn29/fn2902.pdf

Summary:
• Bandwidth 12MHz
• Input Impedance 500MΩ
• Input Bias Current 1nA
• Input Offset Current 1nA
• Input Offset Voltage 0.5mV
• Gain 150kV/V
• Slew Rate 7V/µs

The data sheet has a 2006 date & there weren't many sites offering them,
but a couple that did had prices up to $43! Each! WTF? What makes
these so dear? (It's probably obvious, but not to me, if so please
excuse my newbie-ness.)

Most likely because in this day and age a TO-can for an opamp makes it a
boutique part, just like a ceramic DIP package would. Maybe there were
also some incantations, those can be expensive :)
 
J

Joerg

Jan 1, 1970
0
Vladimir said:
Vsupply max = 45V. A feature of old technology rather then intended high
voltageness.

You don't need such a dinosaur for that. I used a 44V opamp from fresh
production in a design lately, just a regular COTS part from ONSemi I
think. If someone needs to know I can dig it out.

But that one doesn't come in a glass tube or TO can :)
 
J

John S

Jan 1, 1970
0
I found these devices at the "swap shop" at our dump; not having any
idea of what they were. I Googled them and found this:
http://www.intersil.com/content/dam/Intersil/documents/fn29/fn2902.pdf

Summary:
• Bandwidth 12MHz
• Input Impedance 500MΩ
• Input Bias Current 1nA
• Input Offset Current 1nA
• Input Offset Voltage 0.5mV
• Gain 150kV/V
• Slew Rate 7V/µs

The data sheet has a 2006 date & there weren't many sites offering them,
but a couple that did had prices up to $43! Each! WTF? What makes
these so dear? (It's probably obvious, but not to me, if so please
excuse my newbie-ness.)

Bob

Try to find one to buy. Maybe that will tell you something.
 
B

Bob Engelhardt

Jan 1, 1970
0
So, there's nothing special about what they do - it's just the mil
spec-ness and the rarity that costs so.

Thanks,
Bob
 
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