PURPOSE: To determine precisely the operation phase of a circuit element such as a gate and to drive the circuit element synchronously with a driving magnetic field by forming a magnetic resistance element to detect the phase of the driving magnetic field.

CONSTITUTION: The magnetic resistance element 10 is formed on a magnetic bubble memory chip 2. The magnetic resistance element 10 detects the phase of an inside magnetic field driving magnetic bubbles and the operation phases of a swap gate G1 and replicator gate G2 are precisely controlled synchronously with the driving magnetic field. Therefore, a large operation phase margin of a magnetic bubble memory device is secured. In addition, an influence based upon the phase difference between a logical driving magnetic field and the real driving magnetic field is removed, the assembling is made easy and the productivity of the magnetic bubble memory device is improved.