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.