Sourcing LM308s?

[bhcarpenter]

Extra mojo for metal can ICs!

These should be legit, I’d think: https://www.jameco.com/z/LM308AH-Major-Brands-IC-LM308AH-Precision-Operational-Amplifier-2-to-18V-500mW_245673.html

edit: see note from Chuck below. Possibly not as reputable as I thought.

 

[Cybercow]

FWIW . . . . this is a list of single opamps I've been compiling over the past few years . . . .

Single Op Amp PIN-FOR-PIN Equivalents/Replacements with Slew Rates & Input Types:

CA3080 - Slew = 50V/µs (OTA); BJT
CA3130 - Slew = 10V/µs; MOSFET (In & Out)
CA3140 - Slew = 9V/µs; FET
LF351N - Slew = 13V/µs; FET
LF356 - Slew = 12V/µs; FET
LM201 - Slew = variable; BJT
LM301 - Slew = variable; BJT
LM308 - Slew = 0.3V/µs; BJT
LM148 - Slew = ~0.5V/µs;BJT
LM4250 - Slew = variable; BJT
LM709 - Slew = 0.25V/µs; BJT
LM741 - Slew = 0.5V/µs; BJT
LM748 - Slew = 0.5V/µs; BJT
MC1439 - Slew = ~6V/µs; BJT
MC33171N - Slew = 2.1V/µs; BJT
MCP601 - Slew = 2.3V/µs; MOSFET (In & Out; 6v MAX)
MCP603 - Slew = 2.3V/µs; FET
MUSES03 - Slew = 35V/µs; FET (very expensive)
NE5534 - Slew = 13V/µs; FET
NJU7031 - Slew = 3.5V/μs; FET
OP07CP - Slew = 0.3V/µs; BJT
OPA134 - Slew = 20V/µs; FET
OPA602 - Slew = 20V/µs; FET
OPA1641 - Slew = 20V/µs; FET
TL061 - Slew = 3.5V/µs; FET
TL070 - Slew = 18V/µs; FET
TL071 - Slew = 13V/µs; FET

Slew-Rates below ~0.4V/µs are often detectable by the human ear. Above 0.5V/µs, all bets are off for human ear detection.

The input type has bearing also as it affects the input impedance of the device. BJT - low impedance; FET - high impedance.

 

[fig]

Extra mojo for metal can ICs!

These should be legit, I’d think: https://www.jameco.com/z/LM308AH-Ma...rational-Amplifier-2-to-18V-500mW_245673.html

I bought a tube of the DIP-8s they had and found several duds. They issued a refund. The cans from them seemed to do okay.

 

[fig]

The input type has bearing also as it affects the input impedance of the device. BJT - low impedance; FET - high impedance.

There's a gold nugget.

 

[zgrav]

How many Rats can one man build? before they call him a rodent!

How many parts can one man source? Before they call him a store!

 

[Chuck D. Bones]

Component mojo always gets lost in the mix. Finger mojo on the other hand..

good pun!

 

[Chuck D. Bones]

FWIW . . . . this is a list of single opamps I've been compiling over the past few years . . . .

Single Op Amp PIN-FOR-PIN Equivalents/Replacements with Slew Rates & Input Types:

CA3080 - Slew = 50V/µs (OTA); BJT
CA3130 - Slew = 10V/µs (OTA); FET
CA3140 - Slew = 9V/µs; FET
LF351N - Slew = 13V/µs; FET
LF356 - Slew = 12V/µs; FET
LM201 - Slew = variable; BJT
LM301 - Slew = variable; BJT
LM308 - Slew = 0.3V/µs; BJT
LM148 - Slew = ~0.5V/µs;BJT
LM4250 - Slew = variable; BJT
LM709 - Slew = 0.25V/µs; BJT
LM741 - Slew = 0.5V/µs; BJT
LM748 - Slew = 0.5V/µs; BJT
MC1439 - Slew = ~6V/µs; BJT
MC33171N - Slew = 2.1V/µs; BJT
MCP601 - Slew = 2.3V/µs; FET
MCP603 - Slew = 2.3V/µs; FET
MUSES03 - Slew = 35V/µs; FET (very expensive)
NE5534 - Slew = 13V/µs; FET
NJU7031 - Slew = 3.5V/μs; FET
OP07CP - Slew = 0.3V/µs; BJT
OPA134 - Slew = 20V/µs; FET
OPA602 - Slew = 20V/µs; FET
OPA1641 - Slew = 20V/µs; FET
TL061 - Slew = 3.5V/µs; FET
TL070 - Slew = 18V/µs; FET
TL071 - Slew = 13V/µs; FET

Slew-Rates below ~0.4V/µs are often detectable by the human ear. Above 0.5V/µs, all bets are off for human ear detection.

The input type has bearing also as it affects the input impedance of the device. BJT - low impedance; FET - high impedance.

CA3130 - not an OTA, MOSFET input & output
CA3140 - MOSFET input
MCP601-MCP604 - MOSFET input & output. Rated for 6V max. Do not run them on 9V.
NE5534 - BJT input

BJT vs. FET input also affects input bias current which affects in-circuit offset voltage.

The opamps that have external compensation caps can have their SR reduced by increasing the comp cap.

It's not just about SR. When opamps are driven to the rails, some of the internal circuitry saturates and how it recovers from saturation can vary significantly from one part # to the next. This is not specified in the datasheet.

 

[thesmokingman]

the lm108 and lm208 are probably easier to find domestically these days, mostly in metal can package ... bonus points if you find a way to use a military flat pack version

 

[pcb rookie]

Ordered some from Banzai and received them about a month ago. I have not used them yet. Hope they are the real thing ...

LM308N :: LF LM Types :: Chips, ICs, OpAmps :: Semiconductors :: Electronic Parts :: Banzai Music GmbH

 

[Chuck D. Bones]

Extra mojo for metal can ICs!

These should be legit, I’d think: https://www.jameco.com/z/LM308AH-Ma...rational-Amplifier-2-to-18V-500mW_245673.html

I would not trust anything from Jameco.

 

[bhcarpenter]

I would not trust anything from Jameco.

Oh really?!? Well shoot. I thought they were reputable.

 

[Chuck D. Bones]

PM @Kpedals and ask him about his dealings with Jameco.

 

[Feral Feline]

So this mojo means we are absolutely not in Kansas anymore? Or Boston?

No, man, you're in Chilliwack...

or maybe Toronto...

No, not ...

Nor ...

 

[Cybercow]

CA3130 - not an OTA, MOSFET input & output
CA3140 - MOSFET input
MCP601-MCP604 - MOSFET input & output. Rated for 6V max. Do not run them on 9V.
NE5534 - BJT input

BJT vs. FET input also affects input bias current which affects in-circuit offset voltage.

The opamps that have external compensation caps can have their SR reduced by increasing the comp cap.

It's not just about SR. When opamps are driven to the rails, some of the internal circuitry saturates and how it recovers from saturation can vary significantly from one part # to the next. This is not specified in the datasheet.

Thanks for the corrections.

 

[Matmosphere]

OP, are you in the states or Europe, or elsewhere. If you are in Europe I might know a guy that has some metal can ones.