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The Hall elements form an equivalent Wheatstone (resistor) bridge circuit. Offset voltage may be generated by a differenTIal in this bridge resistance, or can arise from changes in resistance due to package or bonding stress. A dynamic offset cancellaTIon circuit is employed to cancel this offset voltage. When Hall elements are connected as shown in Fig. 40 and a magneTIc field is applied perpendicular to the Hall elements, voltage is generated at the mid-point terminal of the bridge. This is known as Hall voltage. Dynamic cancellaTIon switches the wiring (shown in the figure) to redirect the current flow to a 90˚ angle from its original path, and thereby cancels the Hall voltage. The magnetic signal (only) is maintained in the sample/hold circuit during the offset cancellation process and then released.