JPH0752622Y2 - Voltage applied current measuring instrument - Google Patents
Voltage applied current measuring instrumentInfo
- Publication number
- JPH0752622Y2 JPH0752622Y2 JP12736489U JP12736489U JPH0752622Y2 JP H0752622 Y2 JPH0752622 Y2 JP H0752622Y2 JP 12736489 U JP12736489 U JP 12736489U JP 12736489 U JP12736489 U JP 12736489U JP H0752622 Y2 JPH0752622 Y2 JP H0752622Y2
- Authority
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- Japan
- Prior art keywords
- voltage
- current
- terminal
- force
- output
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
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- Testing Of Individual Semiconductor Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
- Tests Of Electronic Circuits (AREA)
Description
【考案の詳細な説明】 「産業上の利用分野」 この考案は例えばICテスタに利用され、特に大きな電源
電流の測定に適する電圧印加電流測定器に関する。DETAILED DESCRIPTION OF THE INVENTION "Industrial application field" The present invention relates to a voltage applied current measuring device which is used in, for example, an IC tester and is suitable for measuring a large power supply current.
「従来の技術」 第２図に従来に電圧印加電流測定器を示す。この例はIC
テストにおける被測定IC素子の電源電流を測定するプロ
グラムパワーサプライ（PPS）部11に適用した例であ
る。電圧設定器12は一般にデジタル信号をアナログ電圧
に変換するDA変換器であって、デジタル値で設定された
電圧のアナログ電圧を出力するものである。この電圧設
定器12の出力電圧は抵抗器13を通じて演算増幅器14の反
転入力端に供給される。演算増幅器14の非反転入力端は
共通電位点15に抵抗器10を通じて接続され、出力端は電
流バッファ16に接続され、電流バッファ16の出力側は電
流検出抵抗器17の一端に接続される。電流検出抵抗器17
はこれを流れる電流が例えば数Ａのように大きい場合
は、小抵抗値で電流容量が大きい抵抗器が得難いため、
複数の抵抗器を並列に接続したものを使用していた。例
えば１Ωの抵抗器10個並列に接続して、5A、2.5Wに耐え
るようにしていた。"Prior Art" Fig. 2 shows a conventional voltage applied current measuring instrument. This example is IC
This is an example applied to a program power supply (PPS) unit 11 for measuring a power supply current of an IC device under test in a test. The voltage setter 12 is generally a DA converter that converts a digital signal into an analog voltage, and outputs an analog voltage of a voltage set by a digital value. The output voltage of the voltage setting device 12 is supplied to the inverting input terminal of the operational amplifier 14 through the resistor 13. The non-inverting input terminal of the operational amplifier 14 is connected to the common potential point 15 through the resistor 10, the output terminal is connected to the current buffer 16, and the output side of the current buffer 16 is connected to one end of the current detection resistor 17. Current detection resistor 17
When the current flowing through this is large, for example, several A, it is difficult to obtain a resistor with a small resistance value and large current capacity.
It used what connected several resistors in parallel. For example, 10 resistors of 1Ω were connected in parallel to withstand 5A and 2.5W.
電流検出抵抗器17の他端はフォース線18を通じてパフォ
ーマンスボード19上の被測定IC素子21の電源端子22に接
続される。フォース線は１本で例えば2A程度しか電流を
流すことができないため、この例では３本のフォース線
18a、18b、18cを並列に接続して使用した場合である。
フォース線18が接続された端子22はセンス線23を通じ、
更に帰還抵抗器24を通じて演算増幅器14の反転入力端に
接続される。PPS部11の接地点は第１接地線25を通じて
被測定IC素子21の接地端子26に接続され、その接地端子
26は第２接地線27を通じてPPS部11上の電圧バッファ28
に接続され、電圧バッファ28の出力側は共通電位点15に
接続されて、被測定IC素子21に接地点電位が演算増幅器
14の基準電位とされる。フォース線18及びセンス線23は
共通のシールド29で被覆されて出力ケーブル31とされて
いる。抵抗器10、13、24、演算増幅器14、フォース線1
8、センス線23で反転増幅器32に構成している。The other end of the current detection resistor 17 is connected to the power supply terminal 22 of the IC element under test 21 on the performance board 19 through the force line 18. Since only one force wire can carry a current of only about 2A, in this example, three force wires are used.
This is the case when 18a, 18b, and 18c are connected in parallel and used.
The terminal 22 to which the force line 18 is connected is through the sense line 23,
Further, it is connected to the inverting input terminal of the operational amplifier 14 through the feedback resistor 24. The ground point of the PPS section 11 is connected to the ground terminal 26 of the IC element under test 21 through the first ground wire 25.
26 is a voltage buffer 28 on the PPS unit 11 through the second ground line 27.
The output side of the voltage buffer 28 is connected to the common potential point 15, and the ground potential of the IC element under test 21 is connected to the operational amplifier.
14 reference potentials. The force line 18 and the sense line 23 are covered with a common shield 29 to form an output cable 31. Resistors 10, 13, 24, operational amplifier 14, force line 1
8. The sense line 23 constitutes an inverting amplifier 32.
電圧設定器12の出力電圧とセンス線23を通じて与えられ
る端子22の電圧との差がなくなるように演算増幅器14が
動作し、端子22に電圧設定器12の出力電圧、つまり設定
電圧が印加される。この電圧印加により、この例では被
測定IC素子21の電源電流が流れ、この電流はフォース線
18に流れ、この電流に応じて電流検出抵抗器17に電圧降
下が発生する。電流検出抵抗器17の両端の電位差が差動
増幅器33で検出され、その差動増幅器33の出力電圧はAD
変換器34でデジタル値に変換される。電流検出抵抗器17
の抵抗値が既知であるから、AD変換器34の出力デジタル
値を電流検出抵抗器17を流れる電流値として較正出力す
ることにより、被測定IC素子（被測定物）21の端子22に
電圧を印加し、その時、端子22に流れる電流を測定する
ことができる。The operational amplifier 14 operates so that there is no difference between the output voltage of the voltage setter 12 and the voltage of the terminal 22 given through the sense line 23, and the output voltage of the voltage setter 12, that is, the set voltage is applied to the terminal 22. . By applying this voltage, the power supply current of the IC element under test 21 flows in this example, and this current is the force line.
18 and a voltage drop occurs in the current detection resistor 17 according to this current. The potential difference across the current detection resistor 17 is detected by the differential amplifier 33, and the output voltage of the differential amplifier 33 is AD
It is converted into a digital value by the converter 34. Current detection resistor 17
Since the resistance value of is known, the output digital value of the AD converter 34 is calibrated and output as the current value flowing through the current detection resistor 17, so that the voltage is applied to the terminal 22 of the IC device under test (device under test) 21. The current applied to the terminal 22 can be measured at that time.
「考案が解決しようとする課題」 第２図に示した従来の測定器においてフォース線18に流
れる電流を、電流検出抵抗器17をフォース線18と直列に
挿入して測定しているため、このフォース線18の電流が
大きい場合は、１個で小抵抗値、大電流容量の抵抗器を
安価に入手することが困難であることから、複数の抵抗
器を並列に接続して使用しており、例えば前述のように
10個の並列に接続しており、部品点数が多く、製作に手
間を要した。“Problems to be solved by the device” Since the current flowing through the force line 18 in the conventional measuring instrument shown in FIG. 2 is measured by inserting the current detection resistor 17 in series with the force line 18, When the current of the force line 18 is large, it is difficult to obtain a resistor with a small resistance value and a large current capacity at a low price, so multiple resistors are connected in parallel. , As mentioned above
Since 10 pieces were connected in parallel, the number of parts was large and it took time to manufacture.
「課題を解決するための手段」 この考案によれば被測定物の電圧印加端子と、電流バッ
ファの出力端との間の差電圧が差動増幅器で検出され、
その差動増幅器の出力電圧とフォース線の抵抗値とから
そのフォース線に流れる電流値を求める。つまり、この
考案では電流検出抵抗器として、フォース線の抵抗成分
を利用する。フォース線の長さが例えば6.5〜10mのよう
に比較的長い場合は、フォース線の抵抗値が比較的大き
くなり、十分に実用化することが可能である。[Means for Solving the Problem] According to this invention, the differential voltage between the voltage application terminal of the DUT and the output terminal of the current buffer is detected by the differential amplifier,
The current value flowing through the force line is obtained from the output voltage of the differential amplifier and the resistance value of the force line. That is, in this invention, the resistance component of the force line is used as the current detection resistor. When the length of the force wire is relatively long, for example, 6.5 to 10 m, the resistance value of the force wire becomes relatively large, and it can be sufficiently put to practical use.
なおフォース線の抵抗値を測定できるように、帰還抵抗
器とセンス線との間に直列に第１スイッチを挿入し、そ
の第１スイッチ及び帰還抵抗器の接続点と電流バッファ
の出力端との間に第２スイッチを接続し、電流バッファ
の出力端及びフォース線の接続点と差動増幅器の入力端
との間に第３スイッチを挿入し、フォース線の抵抗を測
定する時は、第１スイッチを開、第２スイッチを閉、第
３スイッチを閉又は開とする。In order to measure the resistance value of the force line, a first switch is inserted in series between the feedback resistor and the sense line, and the connection point between the first switch and the feedback resistor and the output end of the current buffer are connected. A second switch is connected between them, and a third switch is inserted between the output terminal of the current buffer and the connection point of the force line and the input terminal of the differential amplifier. When measuring the resistance of the force line, the first switch is used. The switch is opened, the second switch is closed, and the third switch is closed or open.
「実施例」 第１図はこの考案の実施例を示し、ICテスタにおける被
測定IC素子の電源電流の測定の適用した場合であり、第
２図と対応する部分に同一符号を付けてある。この例は
フォース線18を１本乃至３本選択的に使用できるように
した場合で、電流バッファ16の出力端とフォース線18
a、18b、18cとの間にそれぞれスイッチ35a、35b、35cが
直列に挿入される。またセンス線23に電流を流さないよ
うに、センス線23と帰還抵抗器24との間に高入力インピ
ーダンスのバッファ回路36が挿入される。出力ケーブル
31が高速動作するように、バッファ回路36の出力端が抵
抗器37を通じて出力ケーブル31のシールド29にガード接
続される。[Embodiment] FIG. 1 shows an embodiment of the present invention, which is a case where the measurement of the power supply current of the IC element to be measured in the IC tester is applied, and the portions corresponding to those in FIG. In this example, one to three force lines 18 can be selectively used. The output end of the current buffer 16 and the force line 18 are used.
Switches 35a, 35b and 35c are inserted in series between a, 18b and 18c, respectively. Further, a buffer circuit 36 having a high input impedance is inserted between the sense line 23 and the feedback resistor 24 so that no current flows through the sense line 23. Output cable
The output end of the buffer circuit 36 is guard-connected to the shield 29 of the output cable 31 through the resistor 37 so that the 31 operates at high speed.
この考案では被測定物の端子に対する印加電圧と、電流
バッファ16の出力端の電圧との差が差動増幅器33で検出
される。このため、この例では印加電圧としてバッファ
回路36の出力電圧が差動増幅器33の一方の入力端へ供給
され、電流バッファ16の出力電圧が差動増幅器33の他方
の入力端へ供給される。またフォース線18a、18b、18c
の各抵抗値を測定することができるように、帰還抵抗器
24とバッファ回路36との間にスイッチ38が直列い挿入さ
れ、帰還抵抗器24及びスイッチ38の接続と電流バッファ
16の出力端とスイッチ39で接続され、更に電流バッファ
16の出力端と差動増幅器33の入力端との接続線に直列に
スイッチ41が挿入される。In this invention, the difference between the voltage applied to the terminal of the device under test and the voltage at the output terminal of the current buffer 16 is detected by the differential amplifier 33. Therefore, in this example, as the applied voltage, the output voltage of the buffer circuit 36 is supplied to one input terminal of the differential amplifier 33, and the output voltage of the current buffer 16 is supplied to the other input terminal of the differential amplifier 33. Also force lines 18a, 18b, 18c
Feedback resistor so that each resistance value of
A switch 38 is inserted in series between the 24 and the buffer circuit 36 to connect the feedback resistor 24 and the switch 38 to the current buffer.
Connected to the 16 output terminals by switch 39
A switch 41 is inserted in series with a connection line between the output end of 16 and the input end of the differential amplifier 33.
被測定IC素子21に電圧印加電流測定を行う場合は点線で
示すように、スイッチ38を閉、スイッチ39を開、スイッ
チ41を閉とし、フォース線18及びセンス線23を被測定IC
素子21の電源端子22に接続し、第１、第２接地線25、27
を被測定IC素子21の接地端子26に接続し、フォース線18
に流れる電流、つまり電源端子22の電源電流が大きい場
合はスイッチ35a〜35cをすべて閉とする。この状態で電
圧設定器12を設定して目的とする設定電圧を電源端子22
に印加し、差動増幅器33の出力電圧を測定すると、バッ
ファ回路36の出力端の電圧は電源端子22の電圧と等しい
から、差動増幅器33により、フォース線18の両端間の電
圧、つまり、フォース線18におけるフォース電流が流れ
ることにもとずくフォース線18の抵抗による降下電圧が
検出される。従って差動増幅器33の検出電圧をフォース
線18の抵抗値で割算すればフォース線電流が得られる。
フォース線18を流れる電流が小さい場合は、フォース線
18a〜18cをすべて並列接続すると、その並列抵抗値が小
さく、フォース線での降下電圧も小さくなり、電圧の測
定がやりにくくなるから、スイッチ35a〜35bの１つまた
は２つを開として、２本又は１本のフォース線を利用す
ればよい。When measuring the voltage applied current to the IC device under test 21, as shown by the dotted line, the switch 38 is closed, the switch 39 is opened, the switch 41 is closed, and the force line 18 and the sense line 23 are connected to the IC under test.
It is connected to the power supply terminal 22 of the element 21, and the first and second ground lines 25, 27
To the ground terminal 26 of the IC element under test 21, and connect the force wire 18
When the current flowing through the power supply terminal 22, that is, the power supply current of the power supply terminal 22 is large, all the switches 35a to 35c are closed. In this state, set the voltage setter 12 and set the target set voltage to the power supply terminal 22.
When the output voltage of the differential amplifier 33 is measured, the voltage at the output end of the buffer circuit 36 is equal to the voltage at the power supply terminal 22, so the differential amplifier 33 causes the voltage across the force line 18, that is, The voltage drop due to the resistance of the force line 18 is detected due to the flow of the force current in the force line 18. Therefore, the force line current can be obtained by dividing the detection voltage of the differential amplifier 33 by the resistance value of the force line 18.
If the current flowing through the force wire 18 is small,
If all 18a to 18c are connected in parallel, the parallel resistance value will be small and the voltage drop on the force line will be small, making it difficult to measure the voltage. Therefore, open one or two of the switches 35a to 35b to open 2 One or one force line may be used.
このようにこの考案ではフォース線18を電流検出抵抗器
として兼用しており、従ってフォース線18の抵抗値を知
っておく必要がある。フォース線18の抵抗値を測定する
場合は、実線で示すようにスイッチ38を開、スイッチ39
を閉、スイッチ41を開とし、被測定IC素子21を搭載する
パフォーマンスボードの代りに、基準抵抗器42を搭載し
た診断用パフォーマンスボード43を使用し、その基準抵
抗器42の一端にフォース線18とセンス線23とを接続し、
他端に第１、第２接続線25、27を接続すると共に接地す
る。As described above, in the present invention, the force wire 18 is also used as the current detection resistor, and therefore it is necessary to know the resistance value of the force wire 18. When measuring the resistance value of the force wire 18, open the switch 38 and switch 39 as shown by the solid line.
Closed, switch 41 opened, the performance board for diagnostics with reference resistor 42 is used in place of the performance board with IC device under test 21, and the force wire 18 is attached to one end of the reference resistor 42. And the sense line 23,
The first and second connection lines 25 and 27 are connected to the other end and grounded.
先ずスイッチ35aを閉とし、スイッチ35b、35cを開と
し、電圧設定器12より電圧VBを出力して電流バッファ16
の出力端の電圧をVBに設定し、この時の基準抵抗器42の
フォース線18との接続点の電圧VOを、バッファ回路36、
差動増幅器33を通じてAD変換器34で測定する。この時差
動増幅器33は単なるバッファとして作用する。その後、
スイッチ41を閉として、電流バッファ16の出力電圧VBと
バッファ回路36の出力電圧VS、つまり電圧VOとの差VB−
VOを差動増幅器33で検出してAD変換器34で測定する。フ
ォース線18aの抵抗をRf1とし、基準抵抗器42の抵抗値R
ref（既知）とすると、フォース線18aをながれる電流と
基準抵抗器42を流れる電流とが等しいから次式が成立
つ。First, the switch 35a is closed, the switches 35b and 35c are opened, the voltage V B is output from the voltage setter 12, and the current buffer 16 is output.
The voltage at the output terminal of V is set to V B , and the voltage V O at the connection point between the reference resistor 42 and the force line 18 at this time is set to the buffer circuit 36,
It is measured by the AD converter 34 through the differential amplifier 33. At this time, the differential amplifier 33 acts as a simple buffer. afterwards,
By closing the switch 41, the difference V B − between the output voltage V B of the current buffer 16 and the output voltage V S of the buffer circuit 36, that is, the voltage V O −
V O is detected by the differential amplifier 33 and measured by the AD converter 34. The resistance of the force wire 18a is R f1, and the resistance value of the reference resistor 42 is R
If ref (known) is used, the following equation is established because the current flowing through the force line 18a is equal to the current flowing through the reference resistor 42.
従って となる。 Therefore Becomes
同様にしてスイッチ35bを閉、スイッチ35a、35cを開と
して、その時のVOとVB−VOとを求めてフォース線18bの
抵抗値Rf2を求め、同様にしてフォース線18cの抵抗値R
f3、スイッチ35a、35bを閉とし、35cを開としてフォー
ス線18a、18bを並列接続した時のフォース線の抵抗Rs1/
/Rs2、スイッチ35a、35b、35cを共に閉として、フォー
ス線18a、18b、18cの並列抵抗Rf1//Rf2//Rf3を求める。
これら各場合のフォース線の抵抗値をメモリに記憶して
おき、被測定IC素子21に対する電圧印加電流測定時に、
使用したフォース線の状態に応じて対応するそのフォー
ス線の抵抗値を用いて測定したフォース線の降下電圧か
らフォース線電流値を求める。Similarly, the switch 35b is closed and the switches 35a and 35c are opened, V O and V B −V O at that time are obtained to obtain the resistance value R f2 of the force line 18b, and similarly, the resistance value of the force line 18c is obtained. R
Resistance of the force line when f3 and switches 35a and 35b are closed and 35c is opened and force lines 18a and 18b are connected in parallel R s1 /
/ R s2 and switches 35a, 35b, 35c are all closed, and the parallel resistance R f1 // R f2 // R f3 of the force lines 18a, 18b, 18c is obtained.
The resistance value of the force wire in each of these cases is stored in a memory, and when measuring the voltage applied current to the IC element under test 21,
The force line current value is obtained from the voltage drop of the force line measured using the resistance value of the force line corresponding to the state of the force line used.
上述では、フォース線を３本使用したが、その数は任意
に選ぶことができる。IC素子の電源電流の測定のみなら
ず、一般に、被測定物の端子に電圧を印加し、その端子
に流れる電流を測定する場合に、その電流が比較的大き
く、かつ、フォース線が比較的長い場合には、この考案
を適用できる。In the above description, three force lines are used, but the number can be arbitrarily selected. In general, when a voltage is applied to the terminal of the DUT and the current flowing through the terminal is measured, not only the power supply current of the IC element is measured, but the current is relatively large and the force line is relatively long. In some cases, this invention can be applied.
「考案の効果」 以上述べたようにこの考案によればフォース線を電流検
出抵抗器として兼用するため、特にフォース線電流が大
きい場合に多くの電流検出抵抗器を使用する必要がな
く、部品点数が少なく、かつ安価に作ることができる。“Effect of device” As described above, according to this device, since the force wire is also used as the current detection resistor, it is not necessary to use many current detection resistors especially when the force wire current is large, and the number of parts is reduced. There are few and can be made at low cost.
第１図はこの考案の実施例を示す接続図、第２図は従来
の電圧印加電流測定器を示す接続図である。FIG. 1 is a connection diagram showing an embodiment of the present invention, and FIG. 2 is a connection diagram showing a conventional voltage applied current measuring device.
Claims (1)
し、その反転増幅器の出力を電流バッファへ供給し、そ
の電流バッファの出力側をフォース線を通じて被測定物
の端子に接続し、その端子をセンス線を通じ、更に帰還
抵抗器を通じて上記反転増幅器の反転入力端に接続して
上記電圧設定器の出力電圧を上記端子に印加し、その時
上記フォース線に流れる電流を測定する電圧印加電流測
定器において、 上記端子と上記電流バッファの出力端との間の電圧差を
検出する差動増幅器を備え、その差動増幅器の出力電圧
と上記フォース線の抵抗値とからそのフォース線を流れ
る電流を求めるようにしたことを特徴とする電圧印加電
流測定器。1. An output voltage of a voltage setting device is supplied to an inverting amplifier, an output of the inverting amplifier is supplied to a current buffer, and an output side of the current buffer is connected to a terminal of a device under test through a force wire, A terminal is connected to the inverting input terminal of the inverting amplifier through a sense line and a feedback resistor, and the output voltage of the voltage setting device is applied to the terminal. At that time, the current flowing through the force line is measured. A differential amplifier that detects a voltage difference between the terminal and the output terminal of the current buffer, and detects a current flowing through the force line from the output voltage of the differential amplifier and the resistance value of the force line. A voltage-applied current measuring device characterized in that it is obtained.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12736489U JPH0752622Y2 (en) | 1989-10-31 | 1989-10-31 | Voltage applied current measuring instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12736489U JPH0752622Y2 (en) | 1989-10-31 | 1989-10-31 | Voltage applied current measuring instrument |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0365977U JPH0365977U (en) | 1991-06-26 |
| JPH0752622Y2 true JPH0752622Y2 (en) | 1995-11-29 |
Family
ID=31675123
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12736489U Expired - Fee Related JPH0752622Y2 (en) | 1989-10-31 | 1989-10-31 | Voltage applied current measuring instrument |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0752622Y2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4573094B2 (en) * | 2004-01-19 | 2010-11-04 | 株式会社シマノ | Leisure pants |
| US7403030B2 (en) * | 2004-12-17 | 2008-07-22 | Teradyne, Inc. | Using parametric measurement units as a source of power for a device under test |
| US7271610B2 (en) * | 2004-12-17 | 2007-09-18 | Teradyne, Inc. | Using a parametric measurement unit to sense a voltage at a device under test |
-
1989
- 1989-10-31 JP JP12736489U patent/JPH0752622Y2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0365977U (en) | 1991-06-26 |
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| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |