RU158892U1 - MULTI-CRYSTAL MICRO ASSEMBLY FOR CONTROL OF CURRENT POWER - Google Patents

Abstract

1. A multi-chip microassembly for monitoring the current strength, containing a silicon crystal with a first through circular hole made therein, a planar hub in the form of an open ring contour with a gap, located in an annular recess made in the crystal coaxially with the first hole, a magnetoresistive converter made on a silicon crystal in the hub gap, the magnetically sensitive transducer is made of magnetoresistive strips connected over a bridge circuit, over which a plan is placed rnaya coil configured to generate a magnetic field along the easy axis of the magnetoresistive stripe; the outputs of the bridge circuit are connected to the inputs of the amplification circuit, the crystal of which is placed in a second hole made in a silicon crystal. 2. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that at least two magnetoresistive elements are connected in each arm of the bridge circuit. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that the magnetoresistive strips are made with an anisotropic magnetoresistive effect. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that the magnetoresistive strips are made with a giant magnetoresistive effect. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that the concentrator is made of soft magnetic ferromagnetic material with high magnetic permeability.

Description

The utility model relates to microelectronics and can be used in the construction of magnetic field sensors.

The invention is known according to European application EP 2333567 (IPC G01R 15/20, publ. 06/15/2011), which describes the technical solution of the magnetoresistive transducer of a current sensor containing a crystal with a through circular hole made in it, a hub in the form of an open ring circuit with a gap, and a magnetoresistive transducer located in the gap between the arcs of the hub.

The invention is known according to the application US US 20070096717 (IPC G01R 15/20, published 03.05.2007), which describes the technical solution of the magnetoresistive current sensor transducer containing a silicon crystal with a through circular hole made therein, a planar hub in the form of an open ring a contour with a gap placed in a recess made in the crystal coaxially with the hole, and a magnetoresistive transducer made on a silicon crystal in the gap between the arcs of the concentrator.

The problem the utility model aims to solve is to create a sensor for currents with high sensitivity, a wide dynamic range and stably reproducible parameters during its manufacture.

The technical result obtained by the implementation of the claimed utility model is expressed in increasing the sensitivity of the sensor over a wide temperature range.

To achieve the above technical result, the multi-chip microassembly for monitoring the current strength contains a silicon crystal with a first through circular hole made therein, a planar hub in the form of an open ring contour with a gap, located in an annular recess made in the crystal coaxially with the first hole, a magnetoresistive converter made on a silicon crystal in the hub gap, connected to the inputs of the amplification circuit, the crystal of which is placed in the second hole, you olnennom in a silicon crystal, the magnetoresistive transducer is formed as a bridge-connected magnetoresistive strips, over which the planar coil is placed, adapted to generate a magnetic field along the easy axis of the magnetoresistive strips.

In the particular case of the utility model, at least two magnetoresistive strips are connected in each arm of the bridge circuit.

In the particular case of the utility model, the magnetoresistive strips are made in the form of magnetoresistive strips with an anisotropic magnetoresistive effect.

In the particular case of the utility model, the magnetoresistive strips are made in the form of magnetoresistive strips with a giant magnetoresistive effect.

In the particular case of the utility model, the concentrators are made of soft magnetic ferromagnetic material with high magnetic permeability, for example, of soft magnetic ferromagnetic material with a relative magnetic permeability of at least 1000.

Distinctive features are: the design of a magnetoresistive converter in the form of magnetoresistive strips connected over a bridge circuit, over which a planar coil is placed, configured to form a magnetic field along the axis of easy magnetization of the magnetoresistive strips, the connection of the magnetoresistive transducer to the inputs of the amplification circuit, the crystal of which is placed in the second hole.

The magnetoresistive converter is made on the basis of a bridge circuit for connecting thin-film resistors in the form of magnetoresistive strips, for example, with an anisotropic magnetoresistive effect, which consists in the ability of a ferromagnetic (FeNiCo) film to change its resistance depending on the relative orientation of the current flowing through it and the direction of its magnetization vector. An external magnetic field rotates the magnetization vector of the film by a certain angle, the magnitude of which depends on the direction and magnitude of this field. This leads to a change in the film resistance and a change in the output voltage of the magnetoresistive bridge, respectively. In the magnetoresistive transducer above the magnetoresistive strips there is a planar coil configured to form a magnetic field along the axis of easy magnetization of the magnetoresistive strips. The field created by the coil is used to compensate for the technological imbalance of the bridge sensor or to completely compensate for the measured field when using the sensor in feedback measurements.

The implementation of the magnetically sensitive element in the form of magnetically resistive strips connected by a bridge circuit, with a planar coil arranged to form a magnetic field along the axis of easy magnetization of the magnetoresistive strips above the magnetically sensitive element, the connection of the magnetically sensitive element with a gain circuit mounted in a second hole made in a silicon crystal, lead to an increase in the sensitivity of the sensor over a wide temperature range. The implementation of the magnetoresistive transducer in the form of magnetoresistive strips connected by a bridge circuit, with a planar coil arranged above them, configured to form a magnetic field along the axis of easy magnetization of the magnetoresistive strips, provides a high sensitivity of the transducer to the measured currents and high resolution. Moreover, the use of magnetoresistive nanostructures extends the temperature range of operation, thereby allowing the device to be used in areas with harsh operating conditions. Placing the crystal of the amplification circuit in the hole made in the silicon crystal improves the noise immunity, vibration resistance and thermal stability, which in turn leads to an increase in the sensitivity of the sensor. An additional result is a decrease in weight and size characteristics.

The utility model is illustrated by the following drawings.

FIG. 1 is a schematic illustration of a multi-chip microassembly for monitoring current strength;

FIG. 2 is a schematic illustration of a section of a silicon crystal at the location of the ring concentrator and the magnetoresistive converter of FIG. one.

A multi-chip microassembly for controlling the current strength contains a silicon crystal 1 with a first round through hole 2 made therein, a planar concentrator 3 in the form of an open ring contour with a gap 4, located in an annular recess 5, made in the crystal 1 coaxially with the hole 2, a magnetoresistive converter 6 made on a silicon crystal 1 in the gap 4 between the arcs of the hub 3 (Fig. 1, 2). The outputs of the bridge circuit 6 are connected to the inputs of the amplification circuit 7. The crystal of the amplification circuit 7 is mounted in a second hole made in a silicon crystal. The magnetoresistive converter is made in the form of magnetoresistive strips included in the Wheatstone bridge circuit. Above the magnetoresistive strips there is a planar coil arranged to form a magnetic field along the axis of easy magnetization of the magnetoresistive strips.

The hub is made of cold-rolled permalloy tape.

Depth 5 in silicon 1 is formed by plasma chemical etching with a high aspect ratio (Bosch process). Formed recess 5 allows you to place the magnetic field concentrator 3 as close to the sensitive part of the magnetoresistive element 6.

The current flowing in the conductor placed in the hole 2 creates a magnetic field around. This field is amplified by a planar ring concentrator 3 and recorded by a magnetoresistive transducer 6 located in the gap of the annular magnetic field concentrator 3. Under the action of the field, a differential signal appears at the output of the Wheatstone bridge circuit of the magnetoresistive transducer 6, which is amplified by the amplification circuit 7.

The amplification scheme of KPPN 431313.001 is used.

In a module implemented according to a utility model, a sensitivity to a current of more than 3000 mV / A is achieved.

Claims (5)

1. A multi-chip microassembly for monitoring the current strength, containing a silicon crystal with a first through circular hole made therein, a planar hub in the form of an open ring contour with a gap, located in an annular recess made in the crystal coaxially with the first hole, a magnetoresistive converter made on a silicon crystal in the hub gap, the magnetically sensitive transducer is made of magnetoresistive strips connected over a bridge circuit, over which a plan is placed rnaya coil configured to generate a magnetic field along the easy axis of the magnetoresistive stripe; the outputs of the bridge circuit are connected to the inputs of the amplification circuit, the crystal of which is placed in a second hole made in a silicon crystal. 2. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that at least two magnetoresistive elements are connected in each arm of the bridge circuit. 3. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that the magnetoresistive strips are made with an anisotropic magnetoresistive effect. 4. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that the magnetoresistive strips are made with a giant magnetoresistive effect. 5. A multi-chip microassembly for monitoring the current strength according to claim 1, characterized in that the hub is made of magnetically soft ferromagnetic material with high magnetic permeability.

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