KR101890556B1 - Current sourcing resistive sensor for improving sensing accuracy - Google Patents

Abstract

A current sourcing resistive sensor is disclosed that improves sensing accuracy. The current sourcing resistive sensor of the present invention is a resistance array comprising a plurality of resistive elements arranged on a matrix structure of a plurality of row lines and a plurality of column lines, The resistor array formed between the line and the corresponding column line; A driving block driven to drive the plurality of row lines; And a current sourcing block electrically coupled to the column line selected for the sense node to provide a sense voltage and driven to source current to the selected column line through the sense node. The driving block controls the selected row line to a driving voltage and is driven to drive the unselected row line to a voltage provided from the selected column line. According to the current sourcing resistive sensor of the present invention, the sensing voltage reflects only the sensing current excluding the crosstalk current, and the accuracy of the overall sensing is greatly improved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a current-

The present invention relates to a current sourcing resistive sensor, and more particularly to a current sourcing resistive sensor that improves sensing accuracy.

In recent years, researches have been actively conducted on sensors that convert various types of physical signals into electrical signals. One of them is a resistive sensor which can be used as a tactile sensor or a touch sensor.

The resistive sensor comprises a plurality of resistors arranged on a matrix structure, and each of the plurality of resistors is specified by a row line and a column line. The current flowing through each resistor is reflected to the sensing voltage. At this time, the change of each resistance can be confirmed through the level of the sensing voltage, and the contact state and contact position of the user can be confirmed.

In such a resistance-type sensor, it is important that only the current flowing through the resistance element (hereinafter, referred to as 'sensing current') specified in the sensing voltage is reflected in order to improve the accuracy of sensing.

Fig. 1 is a view for explaining a conventional resistance type sensor, and shows a current sourcing resistance type sensor. In the current sourcing resistive sensor of Fig. 1, it is assumed that the upper left resistive element R11 is specified. In this case, the low line RL1 connected to one side of the resistor R11 is connected to the output of the driving amplifier DAMP and is controlled to the ground voltage VSS. The column line CL1 connected to the other side of the resistor R11 is controlled to a voltage VDETn close to the sense voltage VDET which is an output voltage in accordance with the driving of the current source CSC. The magnitude of the current flowing from the current source CSC to the driving amplifier DAMP through the resistor R11, that is, the sensing current Isen (shown by a dot-dash line in FIG. 1) .

In the current sourcing resistive sensor of FIG. 1, a current flowing through a path made up of resistances R21, R22 and R12 (hereinafter, referred to as 'crosstalk' current, Icr) is also reflected in the sense voltage VDET.

As a result, the current sourcing resistance type sensor of FIG. 1 has a problem that the accuracy of sensing is lowered due to the crosstalk current Icr.

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SUMMARY OF THE INVENTION An object of the present invention is to provide a current sourcing resistance sensor in which the crosstalk current Icr is reduced and the accuracy of sensing is improved as a whole.

According to an aspect of the present invention, there is provided a current sourcing resistance type sensor. The current sourcing resistive sensor of the present invention is a resistance array comprising a plurality of resistive elements arranged on a matrix structure of a plurality of row lines and a plurality of column lines, The resistor array formed between the line and the corresponding column line; A driving block driven to drive the plurality of row lines; And a current sourcing block electrically coupled to the column line selected for the sense node to provide a sense voltage and driven to source current to the selected column line through the sense node. The driving block controls the selected row line to a driving voltage and is driven to drive the unselected row line to a voltage provided from the selected column line.

In the current-sourcing resistive sensor of the present invention having the above configuration, the non-selected row line is controlled to the voltage of the selected column line. Accordingly, no current flows through the resistive element formed between the unselected row line and the selected column line. As a result, according to the current sourcing resistance type sensor of the present invention, the sensing voltage reflects only the sensing current excluding the crosstalk current, and the accuracy of the overall sensing is greatly improved.

A brief description of each drawing used in the present invention is provided.
1 is a view of a conventional current sourcing resistive sensor.
2 illustrates a current sourcing resistive sensor according to an embodiment of the present invention.
FIG. 3 is a view showing an example of operation of the current sourcing resistance type sensor of FIG. 2. FIG.
4 is a view showing a current sourcing resistance type sensor of a comparative example.
5 is a diagram showing a current sourcing resistive sensor according to a modification of the present invention.

For a better understanding of the present invention and its operational advantages, and the objects attained by the practice of the present invention, reference should be made to the accompanying drawings, which illustrate preferred embodiments of the invention, and the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are being provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art.

It should be noted that, in understanding each of the drawings, the same members are denoted by the same reference numerals whenever possible. Further, detailed descriptions of known functions and configurations that may be unnecessarily obscured by the gist of the present invention are omitted.

In describing the contents of the present invention throughout the specification, the meaning of the terms 'electrically connected', 'connected' and 'connected' among individual components is not limited to direct connection, And the connection is made through the intermediary medium while keeping it. The term " transmitted " of an individual signal includes not only a direct meaning, but also an indirect meaning through an intermediate medium while maintaining the property of the signal to some extent or more.

Also, a plurality of expressions for each component may be omitted. For example, a plurality of switches or a plurality of signal lines may be expressed as 'switches', 'signal lines', or may be expressed in a single number, such as 'switch' or 'signal line'. This is because the switches operate in complementary manner and sometimes operate independently. In the case where the signal lines are formed of a plurality of signal lines, for example, data signals having the same property, It is also because there is no need to divide into plural. In this respect, such description is reasonable. Accordingly, similar expressions should be construed in the same sense throughout the specification.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 illustrates a current sourcing resistive sensor according to an embodiment of the present invention. 2, the current sourcing resistive sensor of the present invention includes a resistor array 100, a driving block 200, and a current sourcing block 300.

The resistor array 100 includes a plurality of resistive elements R11, R12, R21, and R22 arranged on a matrix structure including a plurality of row lines RL1 and RL2 and a plurality of column lines CL1 and CL2, .

As used herein, 'resistive element' refers not only to conventional resistors, but also to 'resistive properties' which are intentionally or unintentionally generated.

Each of the plurality of resistance elements R11, R12, R21 and R22 is formed between the corresponding row line RL1 and RL2 and the corresponding column line CL1 and CL2. For example, the resistive element R11 shown on the upper left is formed between the row line R11 and the column line CL1.

In Figure 2, the matrix of the resistor array 100 is composed of two row lines and two column lines, with four resistive elements arranged. However, it will be apparent to those skilled in the art that the matrix of the resistor array 100 may extend to three or more m rows and three or more n column lines, and may extend to (m * n) resistive elements.

Meanwhile, in the present embodiment, the plurality of row lines RL1 and RL2 are exclusively selected from each other, and the plurality of column lines CL1 and CL2 are also implicitly selected from each other. That is, when the row line RL1 is selected, the other row row RL2 is unselected. Then, when the column line CL1 is selected, the other column line CL2 is unselected.

The resistance elements R11, R12, R21 and R22 are specified by the selected row lines RL1 and RL2 and the selected column lines CL1 and CL2.

In the present embodiment, it is assumed that the resistance element R11 in which the row line RL1 and the column line CL1 are selected and located on the upper left is specified. In this case, the first row select signal XRA1 and the first column select signal XCA1 in FIG. 2 are activated, and the second row select signal XRA2 and the second column select signal XCA2 are inactivated.

The driving block 200 is driven to drive the plurality of row lines RL1 and RL2. The driving block 200 includes a driving unit 210 and a row connection unit 230.

The driving unit 210 includes a plurality of driving amplifiers 211 and 212. Each of the plurality of driving amplifiers 211 and 212 is electrically connected to its own output terminal and its negative input terminal and is supplied with a voltage supplied to its positive input terminal, RL1, RL2) are driven.

The row connection unit 220 provides a driving voltage VDR to the positive input terminal of the driving amplifier 211 corresponding to the selected row line RL1, (+) Input terminal of the driving amplifier 212 corresponding to the input signal line RL2.

In the present embodiment, it is assumed that the driving voltage VDR is the ground voltage VSS. However, the driving voltage VDR may be implemented at a different level of fixed voltage (e.g., power supply voltage, etc.). However, in this case, the current direction such as the sensing current Isen and the crosstalk current Icr shown in Figs. 3 to 5 may be changed.

More specifically, the row connection part 220 has a spare end (NPRE), a row connection part 231 and a spare connection part 233.

The row connecting means 231 is connected to the input terminal of the positive driving amplifier 211 corresponding to the selected row line RL1 as the first row select signal XRA1 is activated, (VDR). The row connecting means 231 is connected to the positive input terminal of the driving amplifier 212 corresponding to the unselected row line RL2 as the second row select signal XRA2 is inactivated The preliminary stage (NPRE) is electrically connected.

The preliminary connection means 233 may connect the selected column line CL1 to the preliminary stage NPRE as the first column selection signal XCA1 is activated and the second column selection signal XCA2 is inactivated Connect.

The selected row line RL1 is controlled by the driving voltage VDR (in this embodiment, the ground voltage VSS) by the driving block 200 as described above, and the unselected row line RL2 Is driven by the voltage VDETn (see FIG. 3) of the selected column line CL1.

The current sourcing block 300 is driven to connect the selected column line CL1 to the sense node NSEN that generates the sense voltage VDET. Also, the current sourcing block 300 is driven to supply the sense voltage VDET by sourcing a current to the selected column line CL1 through the sense node NSEN.

Specifically, the current sourcing block 300 includes the sensing node NSEN, the column selection unit 310, and the current source 330.

The column selecting unit 310 electrically connects the column line CL1 selected according to the activation of the first column selecting signal XCA1 to the sensing node NSEN. In addition, the column selecting unit 310 electrically disconnects the column line CL2 and the sensing node NSEN, which are not selected as the second column selection signal XCA2 is deactivated.

The current source 330 generates a sensing voltage VDET by sourcing a current flowing to the sensing node NSEN.

For reference, by the current sourcing block 300, the voltage VDETn of the selected column line CL1 is ideally equal to the sensing voltage VDET. However, due to the voltage drop Vsw of the column connection switch 331, a difference may occur between the voltage VDETn of the selected column line CL1 and the sensing voltage VDET.

Continuing with FIG. 2, in the current sourcing resistance type sensor of the present invention as described above, the unselected row line RL2 is driven to the voltage VDETn of the column line CL1 to be selected. Therefore, the unselected row line RL2 and the selected column line CL1 are controlled to substantially the same voltage. Accordingly, the current flowing through the resistor R21 formed between the row line RL2 and the column line CL1 becomes 'O'.

3, only the sensing current Isen flowing through the specified resistance element R11 is provided to the driving block 200 in the current sourcing block 300, The crosstalk current Icr flowing through the resistive elements R12, R22 and R11 which are not specified is not generated.

In summary, in the current sourcing resistive sensor of the present invention, the sensing voltage VDET generated by current sourcing of the current sourcing block 300 reflects only the sensing current Isen excluding the crosstalk current Icr . As a result, with the current sourcing resistive sensor of the present invention, the accuracy of the overall sensing is improved.

The effect of the current sourcing resistance type sensor of the present invention is more remarkable as compared with the comparative example of Fig.

In the current sourcing resistive sensor of the comparative example of FIG. 4, the sense node NSEN is directly connected to the preliminary stage NPRE.

At this time, although the voltage VDETn of the selected column line CL1 is close to the voltage of the sensing node NSEN, that is, the sensing voltage VDET, by the voltage drop Vsw of the column connection switch 331 The difference may occur as described above.

In this case, a voltage difference is generated between the unselected row line RL2 and the selected column line CL1, and the resistance element R22 formed between the row line RL2 and the column line CL1 A considerable amount of current flows.

Accordingly, in the comparative example of FIG. 4, not only the sensing current Isen but also the crosstalk current Icr is reflected in the sensing voltage VDET.

In summary, the current sourcing resistive sensor of the present invention shown in Fig. 2 has a remarkable effect of sensing accuracy as compared with the current sourcing resistive sensor of the comparative example of Fig.

Meanwhile, the current sourcing resistance type sensor of the present invention can be modified into various forms.

5 is a view showing a current sourcing resistance sensor according to a modification of the present invention. 5, a current sourcing resistive sensor of a modification of the present invention also includes a resistor array 100, a driving block 400, and a current sourcing block 300, similar to the current sourcing resistive sensor of FIG. do.

The resistor array 100 and the current sourcing block 300 of FIGURE 5 may be implemented with the same configuration and functionality as the resistor array 100 and current sourcing block 300 of FIGURE 2, , A detailed description thereof is omitted.

The driving block 400 is also driven to drive the plurality of row lines RL1 and RL2. Specifically, the driving block 400 includes a preliminary stage (NPRE), a driving unit 410, a preliminary connection unit 430, and a row connection unit 450.

The driving unit 410 includes a driving driving amplifier 411 and an auxiliary driving amp 412.

The driving driving amplifier 411 is electrically connected to the output terminal of the driving driving amplifier 411 and the negative input terminal of the driving driving amplifier 411. The driving driving amplifier 411 receives the driving voltage VDR (in this embodiment, Voltage (VSS)).

The auxiliary driving amplifier 412 drives the voltage of the preliminary stage NPRE provided to its positive input terminal by electrically connecting the output stage of the auxiliary driving amplifier 412 with its negative input terminal .

The preliminary connection unit 430 connects the selected column line CL1 to the preliminary stage NPRE as the first column selection signal XCA1 is activated and the second column selection signal XCA2 is deactivated, do.

The output terminal of the driving driving amplifier 411 is electrically connected to the row line RL1 selected by the row connection unit 450 and the output terminal of the auxiliary driving amplifier 412 is connected to the unselected row line RL2. Respectively.

The selected row line RL1 is controlled by the driving voltage VDR by the driving block 400 and the unselected row line RL2 is driven by the voltage of the selected column line CL1 .

5, the non-selected row line RL2 is driven by the voltage VDETn of the column line CL1 to be selected. Therefore, the unselected row line RL2 and the selected column line CL1 are controlled to substantially the same voltage. Accordingly, the current flowing through the resistor R21 formed between the row line RL2 and the column line CL1 becomes 'O'.

Therefore, also with the current sourcing resistive sensor of FIG. 5, as in the current sourcing resistive sensor of FIG. 2, the sensing voltage VDET provided in the current sourcing block 300 is the same as the crosstalk current Icr Reflected sensing current Isen. As a result, the accuracy of the overall sensing improves.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it should be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, Lt; / RTI > or equivalents, even if it is replaced or replaced. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (6)

In a current sourcing resistive sensor,
A resistive array comprising a plurality of resistive elements arranged on a matrix structure comprising a plurality of row lines and a plurality of column lines, each of the plurality of resistive elements being arranged between the corresponding row lines and the corresponding column lines The resistor array being formed;
A driving block driven to drive the plurality of row lines; And
And a current sourcing block electrically coupled to the column line selected for the sense node to provide a sense voltage and driven to source current to the selected column line through the sense node,
The driving block
The selected row line being driven to a drive voltage and driven to drive the unselected row line to a voltage provided from the selected column line.
The driving method according to claim 1,
Wherein the grounding voltage is a ground voltage.
2. The apparatus of claim 1, wherein the driving block
A driving unit including a plurality of driving amplifiers, wherein each of the plurality of driving amplifiers is driven to drive the corresponding row line with a voltage supplied to its input terminal; And
And a driving circuit for supplying the driving voltage to the input terminal of the driving amplifier corresponding to the selected row line and driving the input terminal of the driving amplifier corresponding to the unselected row line to electrically connect the selected column line, And a current source resistor.
4. The apparatus of claim 3, wherein the row connection
Reserve unit;
Row connecting means for supplying the driving voltage to an input terminal of the driving amplifier corresponding to the selected row line and driving the input terminal of the driving amplifier corresponding to the unselected row line to connect the preliminary stage; And
And preliminary coupling means driven to connect the column line selected in the preliminary stage.
The method of claim 1, wherein the current sourcing block
The sensing stage generating the sense voltage;
A column selection unit electrically connecting the selected column line to the sensing unit; And
And a current source for sourcing a current flowing to the sensing stage.
2. The apparatus of claim 1, wherein the driving block
Reserve unit;
The driving driving amplifier being driven to drive and output the driving voltage, and the auxiliary driving amplifier is driven to output the voltage of the preliminary stage, ;
A preliminary connection portion that is driven to electrically connect the column line selected in the preliminary stage; And
And a row connection part electrically connected to the output line of the driving driving amplifier to the selected row line and driven to electrically connect an output terminal of the auxiliary driving amplifier to the unselected row line, Type sensor.

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