JPS58178264A - Digital resistance measuring apparatus - Google Patents

Abstract

PURPOSE:To enable the setting of a broad measuring range per range by measuring a resistance value with one limit value of an AD converter as reference point overlapping a voltage bias voltage generated from a resistor to be measured. CONSTITUTION:A switch 401 is turned to a contact (a) and a bias voltage +VF is applied to an input terminal 101b from a bias voltage source 402. The voltage +VF shall correspond to the limit value on the positive side of an A/D conversion area of an A/D converter 104. Current 303 flows through a resistor 301 to be measured from a constant current source 302 and a voltage VX develops thereacross. A differential voltage +VF-VX is memorized into a logic controller 105 while the switches 401 and 402 are turned to a contact (b) to apply only the voltage +VF to the input side of a range switching circuit 102, where it is subtracted from the differential voltage +VF-VX and a voltage -VX is obtained to be indicated on a display 106. As +VF is thought to be applied to the A/D converter 104. The A/D conversion of the voltage -VX is enabled up to the range of -2VF.

Description

[Detailed description of the invention] Approximately the known current in this @&A sampling measurement number.

Regarding the voltage IADAD conversion resistance capacity t digitally displayed, we have developed a digital resistance constant device that can extend the resistance value measurement from 1 to 8 to the conventional 800 mm. This is what I am trying to photograph.

<Background of Yamari> A digital display type circuit tester (commonly known as a tester) has been tested in various cities. This digital display type tester #'1II
As I know, KI [current voltage, direct current, alternating current voltage, alternating current, and resistance measurement functions] are used.

The outline of the process is shown in Hatake 1-. In this article, we will explain the configuration in blood flow voltage mode to create a shark's beak. The generated voltage BX is input to the terminals 1011 and 101b.
range switching path 102 and buffer amplification ti
ΔDf exchange knee 104 is supplied through j103. A.D.
'4!11! in conversion 11104! The lIJ foot voltage ~ is converted into a digital code and sent to the logic controller 105.
i is displayed on display l1F106. Note that 107 indicates a panel switch, and the measurement mode is switched by this panel switch.

Range switching 1i1! The IM 102 is controlled by manual switching and control 1 from the logic controller 105.
There are also cases where the auto range switch is automatically switched depending on the number. The example shown in the figure shows an auto-range switching circuit.

Here, if the voltage to be measured Ex of positive polarity and negative polarity 101bK is applied to the input terminal 1011, the polarity display section K(+) sign of the display 106 is displayed. Ota input terminal 10
When * polarity is given to 1m and @#j constant 11EE of positive polarity is given to 101b, an O symbol is displayed in the lk nature p indicator.

In this way, in this type of measurement unit, the voltage is set so that both positive and negative voltages can be applied. This is required. Therefore, as shown in Figure 2, both i! i position t 1 case p ze p potential center in positive direction + ■ r and towards you -
V, 0 range! ! It is made so that it is possible to exchange I with AD.

The l1lI formation in the 10,000-resistance determination mode is shown in connection 3-. In the resistance construction mode, the copper constant resistor -301 is connected to the input terminals 101M and 101b, and the switch 3041
The known i from p constant current −302 by operating on
l[I, tN power supply fi303tm anti-301. The voltage 8 generated across the p resistor 113010 by supplying this current 803 is supplied to the AD converter 104 through the range switch 8102 and the buffer amplifier 10a.
The resistance amount is displayed on the display 11106 after AD conversion.

Here, since one end of the constant voltage #1lII 302 is connected to the common potential point, a voltage of Fi member polarity is not supplied to At)[1116104. Therefore, in the resistance measurement mode, only #'iAD (knee 104 is negative At) is used. Therefore, in resistance measurement mode, A
The fact that only half of the conversion area of the D conversion 6104 is used is a drawback, and the column fixed range per range is narrow.

Especially the range switching 1 way 102t-hand Iw! When operating, it is difficult to set an appropriate range KB for the 4m1t 801 resistance to be selected.

In the case of automatic range switching, the number of range switching steps is large because the range of range for one range is narrow, and this increases the scale of range switching tgIwr, which has the drawback of increasing costs. .

<Object of the Invention> The present invention is intended to provide a Daisimel resistance measurement device that can provide a wide measurement range per range in resistance measurement mode.

<#1 Compliment of the Invention> In this invention, in the resistance measurement mode, a bias voltage is applied to the voltage generated across the resistance to be measured.

This bias voltage is used to adjust the resistor using one limit of the AD converter 6104 as a reference point.

Therefore, according to this invention, the AD function number 104 is
鿟－茟（釜） [It can be used across the entire range.

A wide range of resistance measurements can be taken per range.

<Fishing for fruit propagation of the invention> Fig. 4 yc shows one fruit set of this invention. In the fourth ridge, parts corresponding to those in Figure 1 and Figure 3 of the broom are marked with a 4- symbol.

In this invention, in the resistance measurement mode i, a bias voltage is applied to the voltage generated in the constant resistance t301 on the machine side.
01. In this sword, a switch is used as a hand screw 401 for applying a bias voltage, and nine cases are shown. Two hands! 1k4
The bias voltage +Vyi is applied from the input terminal 101bK bias voltage #402 by switching the green point 1IK to the switch constituting the switch 01. This bias voltage +■r is AD
It corresponds to the positive and negative Kuma Kaiyari in the ^D transformation 811 area of conversion number 104.

乎8401 is the contact point [When selected, switch 402
is selected atS, and AD is output through the voltage range switching (b) path 102 of the input terminal 101m and the buffer amplifier b103.
It is supplied to the f converter 104. In the resistance measurement mode, the switch 304 is turned on, and a current 303 flows through the constant current source 302 through the resistor 801, and a voltage, for example, is generated across the constant current source 302. . Resistor 301
The voltage R30 supplied from the constant current source 302 is adjusted such that the voltage vx generated at
Adjust the direction of 3.

Therefore, the input of the range switching circuit 1020 is given a difference of 10v, -vx between the bias voltage 1vr and the voltage 2 generated at the column constant resistor number 301. This difference voltage + VF - V
x is temporarily stored in the memory of the ROSIC controller 105 (as well as being stored, the controller 105 stores it in the switch 401
．． 4021 Ke point bKIl exchange. Due to this switching, only the voltage +■r of the bias voltage @402 is applied to the input I11 of the range switching path 102, and this bias voltage +vlt
- Differential voltage +V previously stored in memory, -V from 'e'
Calculate R. By this subtraction, the logic controller 105
is the voltage −vxt− generated across the measuring resistor 301
You can get the resistance amount [#l! can be shown.

<Effects of the Invention> Therefore, according to the present invention, in the constant mode of resistance #j,
Since the bias voltage +v and t1xJ are applied to the voltage generated at the constant resistor -301 to the voltage -v8 and the voltage generated at the constant resistor 301, it can be assumed that the ADi converter 104 has been given +vlO in advance. Wearing jin and ga de.

Therefore, as is clear from the second ail', the voltage -vx generated across the fixed resistor ti301 can be converted to ADi up to an I@ range of -2Vv. Therefore, according to the present invention, the resistance measurement range per lunge can be doubled compared to the conventional method. Therefore, the number of steps for switching the measurable range v5 in resistance measurement mode can be set to [i], so in the case of manual range switching, the number of switching contacts of the range switching switch can be set to 100, and the number of switching contacts of the range switching switch can be set to 100. The shape can be made smaller. Also, when using an auto range switching circuit, the number of stages for range switching can be reduced to 1 compared to the conventional one, which has the advantage of reducing the *JL ratio of the 1llI# circuit for switching the range, and in this respect the cost is reduced. Down is J9 (can be a samurai).

In addition, in the above description, by switching the switches 401 and 402, +V
, -Vx and +■, to the range switching circuit 102 and subtracting each measured quantity to erase the bias voltage +VFt- was explained, but the bias voltage source 302 is highly stable. Then this is definitely a must! There is no 2. The reason for this is that a digital value corresponding to bias 1 (pressure + V) is prepared in advance in the logic controller 05, and it can be configured to subtract this digital value from the digital value corresponding to -i +V, -VxK. .

Further, the logic controller 105 is connected to the central processing unit 501 and the central processing unit 501t as shown in FIG.
- ROM that stores program programs that operate in a predetermined order
502, a RAM 503 that takes in the data filter*1 input from ADfm&104, and switches 304, 401.
*g can be performed by the switch drive circuit 504 controlled by the switch drive circuit 402. Also, the calculation processing button t*shows 1
+106.

4. Figure (3) shows the quantity rate. Figure 1 is a block diagram to clarify the structure of the conventional digital table-top type tester used in sharks, and Figure 2 is a block diagram to clarify the structure of the digital table-type tester used in the conventional shark tester. A graph to explain the ADK range of the AD converter, Figure 3 shows the transmission and operation of the conventional digital display type tester's resistance setting mode.
Figure 4 is a block diagram to explain the structure of Kabutogi, and Figure 5 is a block diagram showing the structure of the nine logic controller used in the actual example of the M4 diagram. It is a block diagram.

101allO1b: Input terminal, 102: Range switching circuit, 104: ADi converter, 301: Fixed resistor, 30
2: constant current source, 401: means for supplying bias voltage,
402: Bias voltage source, 403: Switch.

%IFI' Takeda Riken Industrial Co., Ltd. Agent, Fugi 3 Fig. 304 (!S) [-W O Fig. 5-〇5 Written amendment (voluntary) 1980 2, Patent Office member Tomi Demo , Indication of the case: Japanese Patent Application No. 57-605972, Title of the invention: Digital resistance measuring device 3, Relationship to the amendment case: Patent applicant: Takeda Riken Kogyo Co., Ltd. 4, Agent: 114-2 Shin, Shinjuku-ku, Tokyo 21
Sagami Building Akira's column and Drawing 6, Contents of amendment (1) The scope of claims is amended as shown in the attached sheet.

I am corrected.

(31, p. 14, lines 14-15 [Special 2-range switching circuit 1
02] to "Special C: Resistance measurement mode 6: To change the range, change the constant current 303 of the current source (303) (;
"But it's more achievable," he corrected.

(4) Delete "With range switching circuit 102" on page 16, line 12.

(5) In the same book, correct lines 1 and 7, page 8, line 15 [Range switching circuit 102] is corrected to ``buffer amplifier 41103J.''

(Figures 3 and 4 in Figure 61 are corrected as shown in the attached figure.

Claims above (IIA, centering on reference potential (-positive and negative direction 6:
an AD converter that performs AD conversion in the same voltage range;
Constant resistance @ (: A variable constant current source that supplies a current with a known value, C1 Both of this resistor to be measured -5: Means for applying the generated voltage to the above-mentioned person D [*li, D, The above-mentioned resistor to be measured (-generated voltage 6; limit value of one of the above-mentioned resistors (
- a digital resistance measuring device comprising: - means for applying approximately equal bias voltages;

Claims (1)

[Claims] (11^, & Kfiff in positive and negative directions centered on quasi-potential
A ^D converter that converts the high voltage H into AD. B, a constant voltage RIlli that supplies a current that increases the value of the resistor & KR, and C1 a constant resistor of this column 1111! and means for applying the voltage generated in the AD converter to the AD converter. D, the voltage generated by the upper scooped resistor 11iIK (the above-mentioned voltage
A bias turtle is abundant in the ant world on one side of the converter! Et-
a digital resistance #J constant device comprising means for providing;