US 6,211,736 B1 · Signal amplifying circuit for magnetoresistive element

Abstract

A signal amplifying circuit has a differential amplifying circuit, a capacitor and a voltage follower. This circuit takes as input signal the signals outputted from the two terminals of an MR element to which a bias electric current is supplied, and amplifies and outputs the difference in input signals from output terminals. One input terminal of this circuit is connected directly with one of the terminals of the MR element. A capacitor connects the other input terminal of this circuit with the another terminal of the MR element. The two input terminals of this circuit are connected respectively with a non-inverting input terminal and an inverting input terminal of the voltage follower. The voltage follower provides an output to an input terminal of this circuit via a resistance.

Claims8

Dependent claims

A signal amplifying circuit for a magnetoresistive element having first and second terminals, the circuit comprising:

a differential amplifying circuit for amplifying and outputting a difference between input signals received at first and second input terminals from a first terminal and a second terminal of a magnetoresistive element to which a bias current is supplied;
a connection line for directly connecting the first input terminal of said differential amplifying circuit with the first terminal of the magnetoresistive element;
a first capacitor for connecting the second input terminal of said differential amplifying circuit with the second terminal of the magnetoresistive element;
and
a DC offset cancel circuit for canceling a DC offset between the first input terminal and the second input terminal of said differential amplifying circuit.

2 more elements

Dependencies are inferred from the claim text.

Signal amplifying circuit for magnetoresistive element

Life of this patent

Signal amplifying circuit for magnetoresistive element

Life of this patent

Abstract

Claims8