JP2001091593A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device in which the electrical characteristics can be measured accurately by measuring the power supply voltage in the semiconductor device. SOLUTION: The semiconductor device comprises a core block 11 arranged to realize a set function, power supply pins 13 connected with the core block 11 and supplying a power supply voltage thereto, a reference pin 14 being supplied with a voltage for evaluating the power supply voltage supplied to the power supply pins 13, and a comparison circuit 12. The comparison circuit 12 has a first terminal for connecting interconnection between the power supply pins 13 and the core block 11, and a second terminal for connecting the reference pin 14. The comparison circuit 12 compares an input voltage to the first terminal with an input voltage to the second terminal and outputs a signal depending on the comparison results.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device, and more particularly to measurement of electrical characteristics of a semiconductor device.

[0002]

2. Description of the Related Art At present, electrical characteristics of a semiconductor device formed on a wafer are measured using a probing card. In measurement using a probing card, a probe for probing is brought into contact with a power supply pin provided on a semiconductor device, and a power supply voltage is supplied into the semiconductor device.

[0003]

However, when the probe is operated at a high frequency using a probing card for measurement, the contact resistance of the probe tip for probing increases, and the power supply voltage supplied to the inside of the semiconductor device is reduced. In some cases. This is due to the increase in the number of probings and the progress of abrasion of the needle tip.
This is because the contact resistance of the needle tip increases. Therefore, there is a problem that an appropriate power supply voltage is not supplied to the inside of the semiconductor device, and the electrical characteristics of the semiconductor device cannot be measured accurately.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a semiconductor device capable of accurately measuring electric characteristics of a semiconductor device by enabling a power supply voltage inside the semiconductor device to be measured. Aim.

[0005]

In order to achieve the above object, a semiconductor device according to the present invention is provided with a circuit block configured to realize a set function and a circuit block connected to the circuit block. A power supply pin provided for supplying a power supply voltage to the block, a reference pin supplied with a voltage for evaluating the power supply voltage supplied to the power supply pin, and connection between the power supply pin and the circuit block A first terminal is connected to the wiring, and a second terminal is connected to the reference pin.
A connection circuit connected to the first terminal and comparing the voltage input to the first terminal with the voltage input to the second terminal, and outputting a signal according to the comparison result. And

In order to achieve the above object, a semiconductor device according to the present invention provides a plurality of circuit blocks configured to realize a set function, and supplies a power supply voltage to the plurality of circuit blocks. A power supply pin provided for a plurality of wirings connecting between the power supply pin and the plurality of circuit blocks, a reference pin supplied with a voltage for evaluating the power supply voltage supplied to the power supply pin,
A first terminal connected to each of the plurality of wirings, a second terminal connected to each of the reference pins,
A plurality of comparison circuits for comparing a voltage input to a terminal with a voltage input to the second terminal and outputting signals corresponding to the comparison result, and receiving signals output from the plurality of comparison circuits. And a block selector for outputting these signals in correspondence with the circuit blocks.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] In the first embodiment, when the electrical characteristics of a semiconductor device are measured using a probing card, accurate measurement cannot be performed due to an increase in contact resistance of a probe tip. This is to eliminate the problem.

FIG. 1 is a block diagram showing an electrical configuration of a semiconductor device according to a first embodiment of the present invention.

As shown in FIG. 1, a power supply pin 13 is connected to first input portions of the core block 11 and the comparison circuit 12. The reference pin 14 is connected to a second input section of the comparison circuit 12. Further, a determination pin 15 is connected to an output section of the comparison circuit 12.

The core block 11 is an aggregate of one or a plurality of circuit blocks for realizing the function of the semiconductor device, and includes a circuit block such as an FPU, an ALU, and a memory. A power supply voltage Vcc is externally applied to the power supply pin 13.
Is supplied. The reference pin 14 is externally supplied with Vcc as a reference voltage. Comparison circuit 1
2 compares the voltage input to the first input unit and the voltage input to the second input unit, and outputs a signal corresponding to the comparison result to the determination pin 15.

The semiconductor device thus configured is operated at a high frequency using a probing card,
The case where the electrical characteristics are measured will be described. In the probing card, a power supply for supplying the power supply voltage Vcc to the power supply pin 13 and a power supply for supplying the power supply voltage Vcc to the reference pin 14 are different from each other.

In the measurement using a probing card, a power supply voltage Vcc is supplied by bringing a needle tip into contact with a power supply pin 13,
The measurement of the electrical characteristics is performed. In such a measurement, dirt such as shavings easily adheres to the needle tip depending on the number of times of probing and the degree of wear of the needle tip. For this reason, the contact resistance of the probe tip to be probed becomes large and cannot be ignored in measurement.

Here, assuming that the contact resistance of the needle tip is R and the current flowing through the core block 11 is I, the core block 1
The power supply voltage supplied to 1 can be represented by Vcc-IR. This Vcc-IR is also supplied to the first input of the comparison circuit 12.

On the other hand, a constant voltage Vcc is supplied from a reference pin 14 to a second input section of the comparison circuit 12. This is because the second input section has a high impedance (HiZ) with respect to the reference pin 14, so that no current flows and no voltage drop IR occurs.

In the comparison circuit 12, the voltages supplied to the first input section and the second input section are compared. By this comparison,
When the difference between the voltage Vcc-IR of the first input section and the voltage Vcc of the second input section is larger than a predetermined voltage, the output section determines whether the determination pin 1
5 outputs “H” (or “L”). Also, Vcc
When the difference between -IR and Vcc is within a predetermined voltage, "L" (or "H") is output from the output unit to the determination pin 15.

Based on the signal output to the determination pin 15, it is possible to determine whether or not the performance of the probing card has deteriorated due to an increase in the contact resistance of the stylus. According to this embodiment, as described above, the power supply voltage inside the semiconductor device can be measured by utilizing the determination result and performing measurement using a probing card having no performance degradation. The electrical characteristics of the device can be accurately measured.

[Second Embodiment] In the second embodiment, in a semiconductor device, a voltage drop state can be grasped for each circuit block such as an FPU, an ALU, and a memory. Here, the circuit blocks of the FPU, the ALU, and the memory will be described as examples.

FIG. 2 is a block diagram showing an electrical configuration of a semiconductor device according to a second embodiment of the present invention.

As shown in FIG. 2, a circuit block F
A power supply pin 24 is connected to the PU 21, the ALU 22, and the memory 23. A connection point between the power supply pin 24 and the FPU 21 is connected to a first input unit of the comparison circuit 21A, and a connection point between the power supply pin 24 and the ALU 22 is connected to the comparison circuit 22A.
Are connected to the first input section of Similarly, power supply pin 24
The connection point between the memory and the memory 23 is connected to the first input section of the comparison circuit 23A.

Further, the comparison circuit 21A and the comparison circuit 22
A, a reference pin 25 is connected to each second input section of the comparison circuit 23A. Comparison circuit 21A,
Output units 22A and 23A are connected to a block selector 26, respectively, and a determination pin 27 is connected to the output unit of the block selector 26.

The power supply pin 24 has a power supply voltage Vcc
Is supplied. A constant voltage Vcc is externally supplied to the reference pin 25 as a reference voltage. The comparison circuit 21A, the comparison circuit 22A, and the comparison circuit 23A compare the voltages input to the first input unit and the second input unit, and output a signal corresponding to the comparison result to the block selector 2A.
6 is output. The block selector 26 receives signals according to the comparison result, converts these signals into serial signals, and outputs the serial signals to the determination pin 27.

Next, the operation of the semiconductor device thus configured will be described.

The semiconductor device is operated at a high frequency using a probing card, and the voltage drop state of the power supply voltage Vcc due to wiring or the like is measured for each circuit block. In the probing card, a power supply for supplying Vcc to the power supply pin 24 and a power supply for supplying Vcc to the reference pin 25 are used separately.

In the measurement using the probing card, the tip of the probe is brought into contact with the power supply pin 24 to supply the power supply voltage Vcc.
The measurement of the electrical characteristics is performed. Since each circuit block has a different circuit configuration in the block, the value of the flowing current is different. Therefore, the power supply voltage supplied to each circuit block is also different.

Here, all the resistors including the wiring and the like to the FPU 21 are R1, and the current flowing through the FPU 21 is I1.
Let it be 1. Then, the power supply voltage supplied to the FPU 21 can be represented by Vcc-I1 * R1. This Vcc-I1
× R1 is supplied to the first input unit of the comparison circuit 21A.

On the other hand, the second input section of the comparison circuit 21A has:
A constant voltage Vcc is supplied from the reference pin 25. This is because the second input section has a high impedance (HiZ) with respect to the reference pin 25, so that no current flows and no voltage drop IR occurs.

In the comparison circuit 21A, the voltages supplied to the first input section and the second input section are compared. By this comparison, when the difference between the voltage Vcc-I1 × R1 of the first input unit and the voltage Vcc of the second input unit is larger than a predetermined voltage, "H" (or "L") is output from the output unit to the block selector 26. Is output. When the difference between Vcc−I1 × R1 and Vcc is within a predetermined voltage, “L” (or “H”) is output from the output unit to the block selector 26.

Further, all the resistors including the wiring and the like for the ALU 22 are represented by R2, and the current flowing through the ALU 22 is represented by I2
And Then, the power supply voltage supplied to the ALU 22 becomes V
It can be represented by cc−I2 × R2. This Vcc-I2 ×
R2 is supplied to a first input of the comparison circuit 22A.

On the other hand, the second input section of the comparison circuit 22A has:
A constant voltage Vcc is supplied from the reference pin 25. The comparison circuit 22A compares the voltages supplied to the first input unit and the second input unit. By this comparison, when the difference between the voltage Vcc-I2 × R2 of the first input unit and the voltage Vcc of the second input unit is larger than a predetermined voltage, "H" (or "L") is output from the output unit to the block selector 26. Is output. Also, V
When the difference between cc−I2 × R2 and Vcc is within a predetermined voltage, “L” (or “H”) is output from the output unit to the block selector 26.

Similarly, all resistors including wiring and the like for the memory 23 are R3, and the current flowing through the memory 23 is I3. Then, the power supplied to the memory 23 can be represented by Vcc-I3 × R3. This Vcc-I
3 × R3 is supplied to a first input unit of the comparison circuit 23A.

On the other hand, the second input section of the comparison circuit 23A has:
A constant voltage Vcc is supplied from the reference pin 25. The comparison circuit 23A compares the voltages supplied to the first input unit and the second input unit. According to this comparison, when the difference between the voltage Vcc-I3 × R3 of the first input unit and the voltage Vcc of the second input unit is larger than a predetermined voltage, "H" (or "L") is output from the output unit to the block selector 26. Is output. Also, V
When the difference between cc−I3 × R3 and Vcc is within a predetermined voltage, “L” (or “H”) is output from the output unit to the block selector 26.

The block selector 26 includes a comparator 21
A signal "H" or "L" indicating the comparison result is received from the output units of A, 22A and 23A. The signal indicating the comparison result is converted into a serial signal by the block selector 26 and output to the determination pin 27.

It is possible to determine whether or not the voltage drop of the power supply voltage Vcc is larger than a predetermined voltage for each circuit block such as an FPU, an ALU, and a memory during measurement of a semiconductor device by a signal output to the determination pin 27. it can.

As described above, according to this embodiment, the power supply voltage inside the semiconductor device can be measured, so that the electrical characteristics of the semiconductor device can be accurately measured.

[Third Embodiment] In the third embodiment, a voltage actually applied to a core block including an FPU, an ALU, a memory and the like in a semiconductor device is measured.

FIG. 3 is a block diagram showing an electrical configuration of a semiconductor device according to a third embodiment of the present invention.

As shown in FIG. 3, the circuit core block 31
The power supply pin 33 is connected to a first input section of the comparison circuit 32. An arbitrary setting pin 34 is connected to a second input section of the comparison circuit 32. Further, a determination pin 35 is connected to an output section of the comparison circuit 32.

The circuit core block 31 is an aggregate of one or a plurality of circuit blocks for realizing the function of the semiconductor device, and includes circuit blocks such as an FPU, an ALU, and a memory. The power supply pin 33 is supplied with a power supply voltage Vcc from outside. A voltage set arbitrarily from the outside is supplied to the arbitrary setting pin 34. The comparison circuit 32 compares the voltages input to the first input section and the second input section, and outputs a signal corresponding to the comparison result to the determination pin 35.

Next, the operation of the semiconductor device thus configured will be described.

The semiconductor device is operated at a high frequency using a probing card, and a power supply voltage V
The voltage actually applied to the core block is measured by the voltage drop of cc. In the probing card, a power supply for supplying Vcc to the power supply pin 33 and a power supply for supplying an arbitrary voltage Vo to the reference pin 34 are used separately.

In the measurement using the probing card, the power supply voltage Vcc is supplied by bringing the tip of the probe into contact with the power supply pin 33. Here, it is assumed that all resistances including wiring and the like for the core block 31 are R, and a current flowing through the core block 31 is I. Then, the power supply voltage supplied to the core block 31 can be represented by Vcc-IR. This Vcc-IR
Is supplied to the first input unit of the comparison circuit 32.

On the other hand, the second input section of the comparison circuit 32 is supplied with an arbitrary voltage Vo from an arbitrary setting pin 34 without causing a voltage drop. This is because the second input section has a high impedance (HiZ) with respect to the arbitrary setting pin 34, so that no current flows and no voltage drop IR occurs.

The comparison circuit 32 compares the voltages supplied to the first input section and the second input section. By this comparison,
The voltage Vcc-IR at the first input and the arbitrary voltage V at the second input
When the difference from o is larger than the predetermined voltage, “H” (or “L”) is output from the output unit to the determination pin 35. Also,
When the difference between Vcc-IR and Vo is within a predetermined voltage, “L” (or “H”) is output from the output unit to the determination pin 35.

When the difference between the voltage Vcc-IR and the arbitrary voltage Vo is larger than a predetermined voltage (when "H" is output),
The arbitrary voltage Vo is changed, and comparison and determination are executed again. This comparison and determination and the change of the arbitrary voltage Vo are repeated, and when the difference between Vcc-IR and Vo is within a predetermined voltage (when “L” is output), the arbitrary voltage Vo at this time is set to the core. This is the voltage actually applied to the block 31.

By performing the above-described measurement in the semiconductor device, the voltage actually applied to the core block including the FPU, the ALU, the memory, and the like can be measured.

As described above, according to this embodiment, the electric characteristics of the semiconductor device can be accurately measured by making the power supply voltage inside the semiconductor device measurable.

[0048]

As described above, according to the present invention, the power supply voltage inside the semiconductor device can be measured,
It is possible to provide a semiconductor device capable of accurately measuring electric characteristics of the semiconductor device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an electrical configuration of a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing an electrical configuration of a semiconductor device according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing an electrical configuration of a semiconductor device according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Core block 12 ... Comparison circuit 13 ... Power supply pin 14 ... Reference pin 15 ... Judgment pin 21 ... FPU 22 ... ALU 23 ... Memory 21A, 22A, 23A ... Comparison circuit 24 ... Power supply pin 25 ... Reference pin 26 ... Block selector 27 ... Judgment pin 31 ... Core block 32 ... Comparison circuit 33 ... Power supply pin 34 ... Arbitrary setting pin 35 ... Judgment pin

Continued on the front page F term (reference) 2G032 AA00 AC03 AD01 AK11 5F038 DF04 DF05 DT12 DT15 DT19 EZ20

Claims (2)

[Claims] A circuit block configured to realize a set function; a power supply pin connected to the circuit block and provided to supply a power supply voltage to the circuit block; and a power supply pin connected to the power supply pin. A first terminal is connected to a reference pin to which a voltage for evaluating the power supply voltage is supplied, and a wiring connecting between the power supply pin and the circuit block, and a second terminal is connected to the reference pin. The voltage input to the first terminal and the second
A comparison circuit that compares a voltage input to a terminal and outputs a signal corresponding to the comparison result. 2. A plurality of circuit blocks configured to realize a set function, a power pin provided to supply a power voltage to the plurality of circuit blocks, the power pin and the plurality of circuit blocks And a reference pin to which a voltage for evaluating the power supply voltage supplied to the power supply pin is supplied, a first terminal is connected to each of the plurality of wirings, and a second terminal Are respectively connected to the reference pins, and the first
A plurality of comparison circuits that compare a voltage input to a terminal with a voltage input to the second terminal and output signals according to the comparison result; and receive signals output from the plurality of comparison circuits. And a block selector for outputting these signals in correspondence with the circuit blocks.