Hi Guys,

I was reading a datasheet for uA741 and there was a note there that I am a bit confuse on what it means. It says "All voltage values, unless otherwise noted, are with respect to the midpoint between VCC+ and VCC–". Can someone please tell me how it is interpreted.

Below is the datasheet link, the statement I placed can be seen on page 4:
http://www.datasheetcatalog.org/datasheet/texasinstruments/ua741.pdf

 

It means the testing was done on symmetrical (like +12V & -12V) power rails.

The nominal 0V for testing is half way between the two.

 

As an example, use +/- 15 volts. The midpoint is 0 volts. Try +15 and -13 - the midpoint is +2 volts. Add the negative voltage to the positive for the midpoint.

I do wish that all those old 741 op amps would just turn to dust and blow away. They are, indeed, op amps, but with so many limitations compared with modern devices. For experimenting with, use something more like a TL071 instead. It's probably less expensive than a 741, and every spec is better.

 

I think a dual opamp (stereo) like a TL072 or a quad (surround sound) like a TL074 cost less per opamp than a single TL071 single (mono) opamp.

The 741 opamp performs poorly at audio frequencies. Also the low power LM358 and LM324 opamps.