| 摘要 |
PURPOSE:To improve an S/N ratio and to decrease the induction of external noise, by forming magnetoresistance effect elements MR and thin film transistor circuit parts of a field effect type on an insulation substrate. CONSTITUTION:Integrated head parts 5 formed with MR head parts and thin film transistor circuit parts of a field effect type are formed on a substrate 4. The electrodes 9 on the conductive layers 3 connecting to both ends of MR elements 2 and the input sides of the thin film transistor circuit parts are electrically connected. Constant current is supplied to each element 2 from the thin film transistors Q1, Q2 of a field effect type. The resistance change of the MR element modulated by an external magnetic field is converted to the voltage change is amplified with an amplifier constituted of thin film transistors Q3- Q13 of a field effect type and is drawn out as an output to the outside. Since the MR element and a preamplifier are formed in extreme proximity to each other in the thin film magnetic field, the sectional area formed of the signal line connecting both is virtually negligible. As a result, the amt. of noise is considerably reduced and the S/N ratio of the reproduction signal is considerably improved. |
