i need to buy some general purpose op amps which are monorail(i mean i can connect the op amp with Vcc and Gnd not Vcc Gnd and -Vcc) any ideas of such opamps.. possibly sold from ebay?
I like the CA3140 and CA3240 OPA,s good single voltage spec and cheap.
My preferred general purpose op-amps (low-cost, pdip package, rail-to-rail if possible, single supply), to complement microcontroller projects, are the following
- MC34074 (OnSemi) - V=3/44, GBW=4.5MHz, Bipolar (no R-R), 0.71€
- MC33174 (OnSemi) - V=3/44, GBW=1.8MHz, Bipolar (no R-R), 0.70€
- MC33204 (OnSemi) - V=2/12, GBW=2.2MHz, Bipolar, 0.96€
- TLV2374 (TI) - V=3/16, GBW=3MHz, CMOS, 0.81€
- TLC274 (TI) - V=3/16, GBW=1.7MHz, CMOS, 0.46€
- TLV2464 (TI) - V=2.7/6, GBW=6.4MHz, CMOS, 1.48€
- LM6134 (NSC) - V=2.7/12, GBW=10MHz, Bipolar, 2.82€
- LMC6484 (NSC) - V=3/15, GBW=1.5MHz, CMOS, 2.55€
- MCP604 (Microchip) - V=2.7/6, GBW=2.8MHz, CMOS, 0.78€
thanks for your reply...
these seem to be much of an overkill considered that i need the op amps for general purposes only... i mean normal (or standard uses) (not for some cutting edge technology )
I would hardly think a 28pence OPA, first manufactured over 15 years ago could be considered cutting edge technology.
For general purpose use the CA3140/3240 is ideal, IMO.
If you are thinking in terms of the 741 type, dont waste your time.
with regards to the general purpose opamp and the cutting edge technology.. the former term was used to stress the point that i need a really basic opamp... just to make things clearer not to provide any comment on any opamps listed above..
why is the LM741 a waste of time ?? (just curiosity)
what i want is an opamp having a single supply and can work with voltages as low as 5V possibly less... thanks regards
Why do you specifically require single supply?, any opamp can work off a single supply, you just bias it at half supply potential, which is all the 'single supply' chips do. 5V or less is really what's limiting you though.
For my analogue PIC tutorial I required an opamp that went down to zero volts and to +2.5V or so. To do this I used a normal cheap opamp along with a negative voltage generator to supply a -5v for it. This allows it to go right down to zero volts, which so called 'rail to rail' devices don't.
The MC33171 single, MC33172 dual and MC33174 quad opamps are low power improvements to the lousy old LM358 dual and LM324 quad opamps.Howz about the MC33171 op_amp?
Try reading the 'sticky' at the top of this very forum.
by the way i am not really sure at the moment but the non inverting single supply circuit posted in the sticky note and in: