What was I thinking?=A0 My last post was wrong.=A0 The offset voltage was w=
rong.=A0 Use the same op-amp, feedback resistor (10K 1%), output RC filter =
(1K; 0.01uF).=A0 Use a single 10K 1% resistor connected from 3.3V supply to=
 the inverting input of the op-amp.=A0 This will result in a gain of 2 and =
an offset voltage of 1.65V (=3D3.3 / 2).=A0 Things to watch out for:=20

1) Noise in 3.3V supply will be coupled into A/D.
2) 3.3V supply MUST be exactly twice zero A output voltage of Ametek sensor=
 and must be stable.
3) This circuit lets A/D cover entire output range of sensor - Having the A=
/D converter cover a smaller part of sensor range will require more gain, a=
nd more accuracy in gain setting and offset reference stability and accurac=
y - probably will require circuit trims.
4) Op-amp must have input offset spec that is lower than 1/2 LSB or circuit=
 trims will be required.
5) If you use capacitor on input of A/D (recommended by Microchip to reduce=
 conversion noise) don't forget isolation resistor between op-amp output an=
d A/D input.=A0 Many, if not most op_amps will oscillate with cap on output=
..

db
--=20
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