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Somebody here will know about op amps...
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Peter
Feb 23, 2021, 7:42:15 AM2/23/21
to
Won't they?
'tis my belief that the muA741 is available two to a DIP. Can anyone
tell me what the name the devices is?
I'm not looking for an equivalent or replacement device, but two 741's
in one package. Common power but each with its own input offset pins.
Googling finds LM747, but this
https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
the op amps therein are 741s.
Needle nardle noo.
--
When, once, reference was made to a statesman almost universally
recognized as one of the villains of this century, in order to
induce him to a negative judgment, he replied: "My situation is
so different from his, that it is not for me to pass judgment".
Ernst Specker on Paul Bernays
'tis my belief that the muA741 is available two to a DIP. Can anyone
tell me what the name the devices is?
I'm not looking for an equivalent or replacement device, but two 741's
in one package. Common power but each with its own input offset pins.
Googling finds LM747, but this
https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
the op amps therein are 741s.
Needle nardle noo.
--
When, once, reference was made to a statesman almost universally
recognized as one of the villains of this century, in order to
induce him to a negative judgment, he replied: "My situation is
so different from his, that it is not for me to pass judgment".
Ernst Specker on Paul Bernays
The Natural Philosopher
Feb 23, 2021, 11:20:53 AM2/23/21
to
On 23/02/2021 12:42, Peter wrote:
> Won't they?
>
yup
> 'tis my belief that the muA741 is available two to a DIP. Can anyone
> tell me what the name the devices is?
>
do you really want that old thing? rather than the dozenes of pin
compatible lower noise faster ones?
the 747 is the same electronics in a 14 pin dip
LM348 is two in an 8 pin package- and slightly better ones.
FET input you want a TL072
low noise an LM833 is good
> I'm not looking for an equivalent or replacement device, but two 741's
> in one package. Common power but each with its own input offset pins.
>
> Googling finds LM747, but this
> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
> the op amps therein are 741s.
>
> Needle nardle noo.
>
Who cares. no two manufacturers 741s were ever the same anyway.
They met a basic spec. All the above meet that spec too and more
--
"First, find out who are the people you can not criticise. They are your
oppressors."
- George Orwell
> Won't they?
>
yup
> 'tis my belief that the muA741 is available two to a DIP. Can anyone
> tell me what the name the devices is?
>
compatible lower noise faster ones?
the 747 is the same electronics in a 14 pin dip
LM348 is two in an 8 pin package- and slightly better ones.
FET input you want a TL072
low noise an LM833 is good
> I'm not looking for an equivalent or replacement device, but two 741's
> in one package. Common power but each with its own input offset pins.
>
> Googling finds LM747, but this
> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
> the op amps therein are 741s.
>
> Needle nardle noo.
>
They met a basic spec. All the above meet that spec too and more
--
"First, find out who are the people you can not criticise. They are your
oppressors."
- George Orwell
Theo
Feb 23, 2021, 11:46:28 AM2/23/21
to
Peter <peterxp...@hotmail.com> wrote:
> Won't they?
>
> 'tis my belief that the muA741 is available two to a DIP. Can anyone
> tell me what the name the devices is?
>
> I'm not looking for an equivalent or replacement device, but two 741's
> in one package. Common power but each with its own input offset pins.
>
> Googling finds LM747, but this
> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
> the op amps therein are 741s.
They are. The Fairchild uA747 was a dual uA741, and I assume the LM747
> Won't they?
>
> 'tis my belief that the muA741 is available two to a DIP. Can anyone
> tell me what the name the devices is?
>
> I'm not looking for an equivalent or replacement device, but two 741's
> in one package. Common power but each with its own input offset pins.
>
> Googling finds LM747, but this
> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
> the op amps therein are 741s.
was National Semiconductor's (now TI) clone of it. See page 76 of the
Fairchild databook:
https://media.searchelec.com//specshee/FAIRCHI/1973_Fairchild_Linear_Integrated_Circuits_Data_Catalog.pdf
But do you really need a 741? Op amps have improved immensely since the 741
was designed in 1968.
Theo
Peter
Feb 23, 2021, 12:52:49 PM2/23/21
to
The Natural Philosopher wrote:
> On 23/02/2021 12:42, Peter wrote:
>> Won't they?
>>
> yup
>
>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>> tell me what the name the devices is?
Should have been "what the name of the device". Sorry.
> On 23/02/2021 12:42, Peter wrote:
>> Won't they?
>>
> yup
>
>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>> tell me what the name the devices is?
>>
> do you really want that old thing? rather than the dozenes of pin
> compatible lower noise faster ones?
>
> the 747 is the same electronics in a 14 pin dip
>
> LM348 is two in an 8 pin package- and slightly better ones.
>
> FET input you want a TL072
>
> low noise an LM833 is good
>
>
>
>> I'm not looking for an equivalent or replacement device, but two 741's
>> in one package. Common power but each with its own input offset pins.
>>
>> Googling finds LM747, but this
>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>> the op amps therein are 741s.
>>
>> Needle nardle noo.
>>
>
> Who cares. no two manufacturers 741s were ever the same anyway.
> They met a basic spec. All the above meet that spec too and more
Thank you. I shall get me an LM747 y'all. ("y'all" seems to go with "I
> do you really want that old thing? rather than the dozenes of pin
> compatible lower noise faster ones?
>
> the 747 is the same electronics in a 14 pin dip
>
> LM348 is two in an 8 pin package- and slightly better ones.
>
> FET input you want a TL072
>
> low noise an LM833 is good
>
>
>
>> I'm not looking for an equivalent or replacement device, but two 741's
>> in one package. Common power but each with its own input offset pins.
>>
>> Googling finds LM747, but this
>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>> the op amps therein are 741s.
>>
>> Needle nardle noo.
>>
>
> Who cares. no two manufacturers 741s were ever the same anyway.
> They met a basic spec. All the above meet that spec too and more
shall get me".)
Peter
Feb 23, 2021, 12:54:15 PM2/23/21
to
> Op amps have improved immensely since the 741
> was designed in 1968.
>
> Theo
>
Peter
Feb 23, 2021, 8:07:34 PM2/23/21
to
The Natural Philosopher wrote:
> On 23/02/2021 12:42, Peter wrote:
>> Won't they?
>>
> yup
>
>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>> tell me what the name the devices is?
>>
> do you really want that old thing? rather than the dozenes of pin
> compatible lower noise faster ones?
>
> the 747 is the same electronics in a 14 pin dip
>
> LM348 is two in an 8 pin package-
or four in a 14 pin package. I might get one to play with.
> On 23/02/2021 12:42, Peter wrote:
>> Won't they?
>>
> yup
>
>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>> tell me what the name the devices is?
>>
> do you really want that old thing? rather than the dozenes of pin
> compatible lower noise faster ones?
>
> the 747 is the same electronics in a 14 pin dip
>
> LM348 is two in an 8 pin package-
> and slightly better ones.
>
> FET input you want a TL072
>
> low noise an LM833 is good
>
>
>
>> I'm not looking for an equivalent or replacement device, but two 741's
>> in one package. Common power but each with its own input offset pins.
>>
>> Googling finds LM747, but this
>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>> the op amps therein are 741s.
>>
>> Needle nardle noo.
>>
>
> Who cares. no two manufacturers 741s were ever the same anyway.
> They met a basic spec. All the above meet that spec too and more
>
>
--
The Natural Philosopher
Feb 23, 2021, 9:52:18 PM2/23/21
to
On 23/02/2021 17:54, Peter wrote:
> Theo wrote:
>> Peter <peterxp...@hotmail.com> wrote:
>>> Won't they?
>>>
>>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>>> tell me what the name the devices is?
>>>
>>> I'm not looking for an equivalent or replacement device, but two 741's
>>> in one package. Common power but each with its own input offset pins.
>>>
>>> Googling finds LM747, but this
>>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>>> the op amps therein are 741s.
>>
>> They are. The Fairchild uA747 was a dual uA741, and I assume the LM747
>> was National Semiconductor's (now TI) clone of it. See page 76 of the
>> Fairchild databook:
>> https://media.searchelec.com//specshee/FAIRCHI/1973_Fairchild_Linear_Integrated_Circuits_Data_Catalog.pdf
>>
>>
>> But do you really need a 741?
>
> Maybe not. I'm just playing, and they're cheap.
>
I've got some TL072s dual and some quad opamps - LM324?? not sure lying
> Theo wrote:
>> Peter <peterxp...@hotmail.com> wrote:
>>> Won't they?
>>>
>>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>>> tell me what the name the devices is?
>>>
>>> I'm not looking for an equivalent or replacement device, but two 741's
>>> in one package. Common power but each with its own input offset pins.
>>>
>>> Googling finds LM747, but this
>>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>>> the op amps therein are 741s.
>>
>> They are. The Fairchild uA747 was a dual uA741, and I assume the LM747
>> was National Semiconductor's (now TI) clone of it. See page 76 of the
>> Fairchild databook:
>> https://media.searchelec.com//specshee/FAIRCHI/1973_Fairchild_Linear_Integrated_Circuits_Data_Catalog.pdf
>>
>>
>> But do you really need a 741?
>
> Maybe not. I'm just playing, and they're cheap.
>
around doing sod all
They all 'work'
--
The biggest threat to humanity comes from socialism, which has utterly
diverted our attention away from what really matters to our existential
survival, to indulging in navel gazing and faux moral investigations
into what the world ought to be, whilst we fail utterly to deal with
what it actually is.
Peter
Feb 23, 2021, 10:09:18 PM2/23/21
to
The Natural Philosopher wrote:
> On 23/02/2021 17:54, Peter wrote:
>> Theo wrote:
>>> Peter <peterxp...@hotmail.com> wrote:
>>>> Won't they?
>>>>
>>>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>>>> tell me what the name the devices is?
>>>>
>>>> I'm not looking for an equivalent or replacement device, but two 741's
>>>> in one package. Common power but each with its own input offset pins.
>>>>
>>>> Googling finds LM747, but this
>>>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>>>> the op amps therein are 741s.
>>>
>>> They are. The Fairchild uA747 was a dual uA741, and I assume the LM747
>>> was National Semiconductor's (now TI) clone of it. See page 76 of the
>>> Fairchild databook:
>>> https://media.searchelec.com//specshee/FAIRCHI/1973_Fairchild_Linear_Integrated_Circuits_Data_Catalog.pdf
>>>
>>>
>>> But do you really need a 741?
>>
>> Maybe not. I'm just playing, and they're cheap.
>>
> I've got some TL072s dual and some quad opamps - LM324??
The LM324 looks interesting in that it uses either single or dual power
> On 23/02/2021 17:54, Peter wrote:
>> Theo wrote:
>>> Peter <peterxp...@hotmail.com> wrote:
>>>> Won't they?
>>>>
>>>> 'tis my belief that the muA741 is available two to a DIP. Can anyone
>>>> tell me what the name the devices is?
>>>>
>>>> I'm not looking for an equivalent or replacement device, but two 741's
>>>> in one package. Common power but each with its own input offset pins.
>>>>
>>>> Googling finds LM747, but this
>>>> https://www.ti.com/lit/ds/symlink/lm747.pdf doesn't actually say that
>>>> the op amps therein are 741s.
>>>
>>> They are. The Fairchild uA747 was a dual uA741, and I assume the LM747
>>> was National Semiconductor's (now TI) clone of it. See page 76 of the
>>> Fairchild databook:
>>> https://media.searchelec.com//specshee/FAIRCHI/1973_Fairchild_Linear_Integrated_Circuits_Data_Catalog.pdf
>>>
>>>
>>> But do you really need a 741?
>>
>> Maybe not. I'm just playing, and they're cheap.
>>
> I've got some TL072s dual and some quad opamps - LM324??
supplies. All (or almost all) the 741 circuits use dual power supplies.
I thought I'd build an FET input voltmeter, maybe this:
https://billingtonrepairs.files.wordpress.com/2015/09/voltmeter.pdf.
The datasheet for the CA3140
https://www.mouser.co.uk/datasheet/2/698/REN_ca3140_a_DST_20170525-1528519.pdf
has interesting applications.
It's three o'clock in the morning--I must go to bed.
> not sure lying
> around doing sod all
>
> They all 'work'
>
>
--
Theo
Feb 24, 2021, 5:49:55 AM2/24/21
to
Peter <peterxp...@hotmail.com> wrote:
> The LM324 looks interesting in that it uses either single or dual power
> supplies. All (or almost all) the 741 circuits use dual power supplies.
It's worth looking at the current lines of, for example, Microchip:
> The LM324 looks interesting in that it uses either single or dual power
> supplies. All (or almost all) the 741 circuits use dual power supplies.
https://www.microchip.com/en-us/products/amplifiers-and-linear-ics/operational-amplifiers-ics
Most of the annoyances with older opamps (dual rail power supplies,
non-rail-to-rail, low input impedance, terrible offsets, noise, awful
frequency response) are long gone. Something like an MCP6004 is a
respectable opamp these days.
Theo
Peter
Feb 24, 2021, 12:51:25 PM2/24/21
to
Theo wrote:
> Peter <peterxp...@hotmail.com> wrote:
>> The LM324 looks interesting in that it uses either single or dual power
>> supplies. All (or almost all) the 741 circuits use dual power supplies.
>
> It's worth looking at the current lines of, for example, Microchip:
> https://www.microchip.com/en-us/products/amplifiers-and-linear-ics/operational-amplifiers-ics
Thank you. Lots of application notes there, which is nice.
> Peter <peterxp...@hotmail.com> wrote:
>> The LM324 looks interesting in that it uses either single or dual power
>> supplies. All (or almost all) the 741 circuits use dual power supplies.
>
> It's worth looking at the current lines of, for example, Microchip:
> https://www.microchip.com/en-us/products/amplifiers-and-linear-ics/operational-amplifiers-ics
>
> Most of the annoyances with older opamps (dual rail power supplies,
> non-rail-to-rail, low input impedance, terrible offsets, noise, awful
> frequency response) are long gone. Something like an MCP6004 is a
> respectable opamp these days.
>
> Theo
>
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