摘要 |
A pH analyzer (40) is operated to measure pH of a solution (34) by applying a reference electrode current, IREF, to a reference electrode (14) of a pH sensor and an ion-specific electrode current, IGLASS, to an ion-specific electrode (16) of the pH sensor. The currents to the reference electrode (14) and ion-specific electrode (16) are multiplexed to avoid cross-talk. Multiplexing the currents provides a more accurate measurement of electrode impedance for diagnostic purpose. A current spike (54, 58) is optionally added to the reference electrode current to discharge any charge in the solution (34) due to the reference electrode current. |