JPS63142876A - Hall element device - Google Patents

Abstract

PURPOSE:To isolate the input and the output excellently, and to form a Hall element device in a monolithic manner by including a semiconductor Hall element detecting a magnetic field in the fixed direction and a wiring path causing currents to spirally flow through the periphery of the semiconductor Hall element and shaping a magnetic field in the direction of detection of the magnetic field. CONSTITUTION:When a voltage is applied between power input terminals VSS and VDD and a potential higher than a threshold level is applied at a gate input terminal VG, an n channel is formed between a source 3 and a drain 4, and currents flow. When currents are caused to flow through an input-signal wiring path 2 through input terminals VIA, VIB at that time, a magnetic field is generated in the direction vertical to a MOS type Hall element 1, currents between the source 3 and the drain 4 are subject to a Hall effect, and Hall voltage is generated between Hall-effect output terminals HA, HB. When a control pulse signal psiP is turned ON and currents are caused to flow through the MOS type Hall element 1, the Hall voltage proportional to currents flowing between the input terminal pair VIA, VIB is generated between HA and HB. The voltage is input to an amplifier 8 when a control pulse signal psiS is turned ON. The amplified signal is latched, and held as an output signal VO.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a Hall element device, and in particular to signal conversion as an interface in which an input signal is given as a current and an output signal is obtained by a voltage that has no direct influence on the input potential. Regarding equipment.

[Conventional technology]

Conventionally, mechanical relays, photocouplers, etc. have been used as this type of signal conversion means.

Mechanical relays pass a current, which is an input signal, through a coil, and the electromagnetic force attracts a piece of iron, etc., to disconnect the output side circuit and obtain an output.Photocouplers pass the input current to an LED. The source of the light is converted into electricity by a light-receiving element such as a photodiode to obtain an output.

[Problem that the invention seeks to solve]

The above-mentioned mechanical relays have the drawbacks of slow operation speed because they involve mechanical operation, and difficulty in improving durability and miniaturization.In addition, photocouplers are difficult to make monolithic and are highly reliable as semiconductor materials. The disadvantage is that silicon cannot be used.

An object of the present invention is to eliminate this further drawback and provide a complete Hall element device whose input side and output side are well isolated and which can be formed monolithically.

[Means for solving problems]

The Hall element device of the present invention includes a semiconductor Hall element that has a pair of terminals for a current supply source and a pair of Hall effect output terminals and detects a magnetic field in a predetermined direction; and a wiring path that forms a magnetic field in the magnetic field detection direction.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the present invention, and FIG. 2 is a partially sectional perspective view of the MO8 type Hall resistor 1 shown in FIG. An input signal wiring path 2 is provided at the 10th hole of the MO8 type Hall element, and both ends of this manual signal wiring path 2 are connected to input terminals.
, connect to VXB.

M (JS type hole stack +1 is formed on a P type substrate, n type diffusion layers are provided on its four sides, and the opposing position is placed on the source 3.
As drains 4, power input terminals y8. VDDV
The diffusion layers 5 and 6 at the other opposing positions are connected to the Hall effect output terminals HA and HB, respectively, and the gate electrode is the gate input terminal ■. Connect with.

Apply voltage between power supply input terminals VSsVDD and gate input terminal ■. When a potential above the threshold level is applied to source 3. An n-channel is formed between the drains 4 and current flows. At this time, when a current is applied to the input signal wiring path 2 through the input terminals
The Hall effect is exerted on the current between the output terminals HA and the drain 4, and a Hall voltage is generated between the Hall effect output terminals HA and HB.

FIG. 3 is a block diagram of an interface circuit including the embodiment of FIG. MO8 type Hall gate gate input terminal V. A control pulse signal φA from the K control circuit 10 is supplied to the Hall effect output terminal HA.

Connect HB to the input terminal of transfer gate 7.

The gate terminal of this transfer gate 7 is connected to the control circuit 10.
A control pulse signal φ3 is applied, and its output terminal is connected to the input terminal of the amplifier 8.

A control pulse signal φ of a control circuit 100 is applied to a clock input terminal of this amplifier 8, and its output terminal is connected to an input terminal of a latch circuit 9. The clock input terminal of the latch circuit 9 receives the control pulse signal φ of the control circuit 10. is given, and the output of the latch circuit 9 is the output terminal of this interface circuit. becomes.

When the control pulse signal φP is turned ON, MO8 type Hall transducer 1
When a current flows through the input terminals VA, VxB! The Hall voltage proportional to the X current flowing between )IA, H
Occurs between 8 and 8. This voltage is the control pulse signal φ, which is ON.
When the amplifier 81C is turned off, the voltage is held when the signal φ5 is turned off. At this time, if the signal is set to (JFF), the MO8 type Hall element IKi current will not flow, preventing wasted current consumption.The amplifier 8 is an M08 type amplifier with high human power impedance, and the control pulse φ is used as the clock input. As a dynamic amplifier, the current consumption can be reduced.The signal output from the amplifier is input to the latch circuit 9, and is latched by the control pulse φ.
.

will be held as . As described above, it becomes possible to amplify and output a weak Hall voltage as a monolithic IC.

It is. The source 3 of the Hall element 1 is grounded, and the drain 4
Connect it to the power terminal ■DD, and connect it to the input signal wiring path for 21 m.
wiring layers 21 and 22 are used. Input current is input terminal
From A, pass through the wiring path 21 of the first layer, go around the MO8 type hole cursor for a plurality of 1gI, and from the contact 23 to the second layer.
In the wiring path 22 of the layer, the signal $p turns several times in the same direction and flows to the input terminal 2.

By turning the wiring path multiple times in this way, it is possible to generate a strong magnetic field for the same current. If the number of wiring layers is further increased, even greater output can be obtained.

FIG. 5 is a layout diagram of a third embodiment of the present invention.

Here, two of the embodiments shown in Fig. 4 are connected in series.
One input signal wiring path is reversed from the other. In other words, the input current flows from the input terminal VXA to the wiring path 3 of the first layer.
1 in a clockwise direction, enters the wiring path 33 of the second layer from the contact 32, continues clockwise, then counterclockwise around the next M08 Hall element, and flows from the contact 34 to the first layer. .

If this is done, the directions of the magnetic fields generated for the two MO8 hole S atoms will be in opposite directions. Also, source 36.
41 is grounded, and the drains 37 and 40 are connected to the power supply terminal vDD.
When connected to the terminals 38 and 39 so that the current flows in opposite directions to the left and right, the terminal 4
The Hall voltages between 2.43 and 2.43 are in the same direction in the upper and lower directions, and when terminals 39 and 42 are connected, a voltage obtained by adding the respective Hall voltages is obtained between HA connected to terminal 38 and terminal 43.

In this way, a large number of input terminal wiring paths fMO8 can be provided near the Hall element, and the radius of the wiring path can be made relatively small to efficiently generate a magnetic field. Furthermore, using magnetic fields in opposite directions has the advantage that they mutually compensate for the effects of external electromagnetic wave noise.

Here, two blocks are connected in series, but the effect will increase if more blocks are connected. Furthermore, if the block is rotated by 90° and connected with the flow direction directly aligned, there is an effect of compensating for the difference in carrier mobility due to the difference in crystal orientation.

Here, we will consider the magnetic field created by the input terminal and the Hall voltage generated by the magnetic field.

As is often said, the circular current i (A
) rotates n times, the magnetic field B created at its center is E? Can be seen.

However, μ. =4π×lO [Henry/m].

1 [quaver work/m2) = 10’ C Gauss].

The M08 type hole stack 1 shown in this example is 100 μm on a side.
If it is a square and the input signal path #S path 2 is near it, then 2a=xoo (μm), and these are (1
) Substituting into the formula yields the following:

-Man, paper in ``Journal of the Institute of Electrical Engineers of Japan,'' Vol. 102, No. 5, p. 384, ``
According to the integrated magnetic sensor, the Hall voltage vH is expressed by the following equation.

■H=-α(W/L)μnvDDB ・・・・・・・・・
・-(3) However, α: Shape effect coefficient due to short-circuit effect of poles W: Channel width L: Channel length where a=s OO Gax, It will be done. For example, in Figure 5, if the number of turns in the valley wiring layer is 10, then n = 20 in two layers.
．． By substituting the 11 current into equation (2) with t = 0.2 s A, the Hall voltage generated in the two Hall elements is 15 mV each, giving a total of 30 mV.If an amplifier is further provided, an interface circuit can be realized. .

〔Effect of the invention〕

As explained above, the present invention generates a magnetic field using a current, which is a human input signal, and uses the voltage generated by the Hall effect due to the magnetic field as an output signal, thereby operating the input side and the output side with separate power supplies. It is possible to obtain a monolithic conductor package with very good input and output isolation. It goes without saying that the Hall element and its peripheral circuit can also be realized using a bipolar type circuit.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the first embodiment of the present invention, and FIG. 2 is a perspective view of the first embodiment of the present invention.
FIG. 3 is a block diagram of an interface circuit that implements the embodiment of FIG. 1, and FIG. 4 is a layout diagram of a second embodiment of the present invention. , FIG. 5 is a layout diagram of a third embodiment of the present invention. 1... M08 type Hall element, 2... Input signal wiring + tM path, 3, 36.41... Source, 4, 37.40... Drain ,5,6,3
8, 39, 42, 43... Diffusion +d terminal, 7
...Transfer gate, 8...Amplifier, 9...Latch circuit, 10...Control circuit %21, 31, 35...No. 1 layer wiring path,
22.33...2nd layer wiring route, 23,32°34...Contact, from VXA, V...
...Input terminal pair, HA, HB...Hall effect output terminal pair, vo...Gate input terminal, vDDV
s8...Mino input terminal pair. Half l Wa Iwa 2 Figure 3 Concave buttocks 4 Ro'Ja HA HB Shin S Figure

Claims (1)

[Claims] A semiconductor Hall element that has a current supply source terminal pair and a Hall effect output terminal pair and detects a magnetic field in a predetermined direction, and a wiring path that flows a current in a spiral around the Hall element and forms a magnetic field in the magnetic field detection direction. A Hall element device comprising: