[sdiy] OpAmp question

[Ken Stone]

Use LM339 comparators, powered from 0V and +15V. From their outputs, run a
resistor to +5V. The value of this resistor will depend on what you are
driving. 
The 339 is open collector. It will pull to ground. It is a comparator so it
will do the job better than an op-amp.

Ken

>That is exactly what I mean.
>
>I designed and built a simple circuit to scan a Fatar keyboard. This circuit 
>uses TL064 comparators to get the binary information key pressed / key not 
>pressed. The TL064 are supplied with 5V and 0V and it seems that they don't 
>do the job correctly. So before I do a redesign of the circuit I want to try 
>opamps which can pull to ground and to 5V.
>
>-Carsten
>
>----- Original Message ----- 
>From: "James Patchell" <patchell at cox.net>
>To: <synth-diy at dropmix.xs4all.nl>
>Sent: Monday, September 05, 2005 10:28 PM
>Subject: Re: [sdiy] OpAmp question
>
>
>> Define single supply....
>>
>> Any opamp can run on a single supply.  Generally, when people say single 
>> supply, they are referring to an opamp whose common mode imput range 
>> includes the negative rail (ground) and whose output can also go down 
>> pretty close to ground....
>>
>> If you do not require either of those atributes...then the TL074/084 fit 
>> the bill....
>>
>>
>> At 01:45 PM 9/5/2005 +0200, Carsten Tönsmann wrote:
>>>Hi list,
>>>
>>>does anybody know a single supply fet input quad opamp which can be 
>>>obtained in DIP? The AD824 only exists in SMD format...
>>>
>>>Thanks in advance
>>>
>>>Carsten
>>
>>         -Jim
>> ***************************************************************
>> http://www.oldcrows.net/~patchell
>>
>> ***************************************************************
>>
>>
>> 
>
>
_______________________________________________________________________
Ken Stone   sasami at hotkey.net.au or sasami at cgs.synth.net
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