Hi all,

I'd appreciate it if anyone could give me some hints on a strange op-amp
problem I'm having:

I have an LMC662 dual CMOS rail-to-rail op-amp hooked up so that one of the
two amps is in a non-inverting buffer config and then other has both inputs
tied to Vdd (5v in this case). Vss is 0 volts.

When I apply a voltage to the non-inverting input,the output follows it
perfectly until I get to  3.7v,at which the output suddently swings up to
5v. If I decrease the non-inv input,the output stays at 5v until I get
below 3.7v at the input at which time it begins to follow the input again.
I also have a scope hooked up to the output and I detect no oscillation or
other strange behavior throughout the entire input range from 0 to 5v.

I have also tried two of these chips(they have a different date code),they
behave the same way!

Am I going crazy,or do I probably have bad chips?! They were shipped in
anti-static foam and I have stored them that way,too.

Thanks,

Sean

|
| Sean Breheny
| Amateur Radio Callsign: KA3YXM
| Electrical Engineering Student
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