Magnetic operational amplifier

Patent metadata

Field	Value
Publication number	US-10879860-B2
Application number	US-201716099902-A
Country	US
Kind code	B2
Filing date	Apr 28, 2017
Priority date	May 10, 2016
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

A magnetic operational amplifier having a differential stage includes a first magnetic field effect transistor MAGFET and a differential signal conditioner, the differential signal conditioner including a load stage, a differential input pair connected to the load stage and a biasing current source connected to the differential input pair; the magnetic field effect transistor MAGFET being connected to the load stage as a second differential input pair and the differential signal conditioner including a second biasing current source connected to the magnetic field effect transistor MAGFET.

First claim

The invention claimed is:

1. A magnetic operational amplifier having a differential stage comprising:
a first magnetic field effect transistor MAGFET and
a differential signal conditioner comprising:
a load stage,
a differential input pair connected to the load stage and
a biasing current source connected to the differential input pair,

wherein the first magnetic field effect transistor MAGFET is connected to the load stage as a second differential input pair and wherein the differential signal conditioner comprises a second biasing current source connected to the magnetic field effect transistor MAGFET.

2. The magnetic operational amplifier according to claim 1 , wherein the first magnetic field effect transistor MAGFET is an n-type magnetic field effect transistor MAGFET.

3. The magnetic operational amplifier according to claim 1 , wherein the differential signal conditioner comprises at least one differential amplification stage to further amplify a signal.

4. The magnetic operational amplifier according to claim 1 , wherein the differential signal conditioner further comprises a chopper to eliminate the offset and low-frequency noise of the differential signal conditioner, the chopper comprising a first stage of modulation of a signal and a second stage of demodulation of the signal, the signal entering the second stage of demodulation being a voltage.

5. The magnetic operational amplifier according to claim 3 , wherein the differential signal conditioner further comprises a chopper to eliminate the offset and low-frequency noise of the differential signal conditioner, the chopper comprising a first stage of modulation of the signal and a second stage of demodulation of the signal, the signal entering the second stage of demodulation being a voltage, and wherein the second stage of demodulation of the chopper is placed after a last differential amplification stage to eliminate the offset and low-frequency noise of the differential signal conditioner and of each differential amplification stage.

6. The magnetic operational amplifier according to claim 1 , further comprising a magnetic sensor connected to the load stage as a second differential input pair and having:
a first configuration corresponding to the first magnetic field effect transistor MAGFET,
a second configuration corresponding to a second magnetic field effect transistor MAGFET,
a third configuration corresponding to a third magnetic field effect transistor MAGFET and
a fourth configuration corresponding to a fourth magnetic field effect transistor MAGFET,

and wherein the differential signal conditioner further comprises a spinning current module to eliminate the offset and low-frequency noise of the magnetic sensor, the spinning current module periodically alternating the first, second, third and fourth configurations of the magnetic sensor.

Assignees

• Univ Strasbourg
• Centre Nat Rech Scient

Inventors

• Frick Vincent
• Osberger Laurent

Classifications

• G01R33/0088

  use of bistable or switching devices, e.g. Reed-switches · CPC title

• H03F15/00

  Amplifiers using galvano-magnetic effects not involving mechanical movement, e.g. using Hall effect · CPC title

• H03F2203/45192

  the differential amplifier contains current mirrors comprising diodes which act as a load for the differential amplifier · CPC title

• H03F2203/45226

  the output signal being switched taken from the one or more output terminals of the differential amplifier · CPC title

• H03F2203/45361

  the AAC comprising multiple transistors parallel coupled at their drains only, e.g. in a cascode dif amp, only those forming the composite common source transistor · CPC title