This electronic pressure gauge uses a Wheatstone bridge-type pressure sensor to drive a 3 1/2 digit A/D converter and a display. IC1 is a pump (quad) that interfaces the bridge sensor to the A/D converter. R16 provides zero adjustment and R6 provides full-scale calibration. D1 through D4 provide temperature compensation. (Reprinted with permission from R-E Experimenters Handbook, 1992, p.31) From figure FE55-36 from Encyclopedia of Electronic Circuits Vol. 1.