JPH06148264A - Measuring method for leakage current - Google Patents

Abstract

PURPOSE:To determine accepted or rejected products by a method wherein a resistance and a relay are connected in series to a power source terminal and a comparator and voltage drops by the product of a leak current and the resistance are compared to measure the leak current. CONSTITUTION:A relay 3 is turned ON to set and apply a desired voltage to a power source supply unit 5 and a time-sharing pattern is inputted into an input terminal 12 of a semiconductor IC device 2 to be measured with a driver 8. At the same time, the internal condition is outputted in time division at an output terminal 11 to complete the internal setting for the measurement of a leakage current of a static power source comparing the results. A voltage drop attributed to an operation power source current Idd flowing through the relay 3 during the setting is almost zero and the voltage at a power source terminal 10 gives a set applied voltage of a unit 5, so that sufficient supply of the power source becomes possible to enable the realization of a normal internal setting. When the internal setting is completed and a static state enters, with the turning OFF of the relay 3, a static power source leakage current Ids of the device 2 flows through a resistance 4 to generate a voltage drop RXIds. The drop voltages thus obtained are compared 6 to judge acceptable or rejected products.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring a leak current of a semiconductor integrated circuit device or the like.

[0002]

2. Description of the Related Art FIG. 2 is a diagram showing a configuration of a conventional method for measuring a quiescent power supply leakage current of a semiconductor integrated circuit device.

As shown in FIG. 2, according to the conventional measuring method, the power supply terminal VDD of the semiconductor integrated circuit device 21 to be measured is L.
The DC unit 23 of the current measuring circuit of the SI tester 22 and the power supply unit 24 are connected through the relay 25,
Further, the input terminal of the semiconductor integrated circuit device 21 under test is the driver unit 26 of the LSI tester 22, and the output terminal of the semiconductor integrated circuit device 21 under test is the LSI.
It is connected to the comparator unit 27 of the tester 22.

A conventional static power supply leak measuring method configured as described above will be described. In order to measure the static power supply leakage current of the semiconductor integrated circuit device under test 21, the relay 25 of the LSI tester 22 is first connected to the DC unit 23 side, and the semiconductor integrated circuit device under test is measured by the driver unit 26 of the LSI tester 22. A voltage of the same level as the voltage applied by the DC unit 23 or a voltage of GND level is applied to the input terminal 21 of the DC unit 23 to measure the static power supply leak current.

Further, the semiconductor integrated circuit device 21 under test is measured.
When it is necessary to set the internal state due to the configuration of the internal circuit of the driver unit 26 of the LSI tester 22,
The internal setting input information, which is time-divided in advance, is patterned and started.

After the start, the comparator unit 27 of the LSI tester 22 compares the output information of the output terminal of the semiconductor integrated circuit device 21 to be measured with the internally set output information pattern which is time-divided in advance to check whether or not it is operating normally. Check to finish setting the internal state.
At that time, the static power supply leak current is measured by the DC unit.

[0007]

However, in the above-mentioned conventional configuration, the semiconductor integrated circuit device 21 under test is measured.
If it is necessary to set the internal circuit of the LSI, it is necessary to operate the internal setting pattern. At that time, the power supply source of the semiconductor integrated circuit device under test 21 is the LSI.
The voltage is applied by the DC unit 23 of the tester 22.

The DC unit 23 of the LSI tester 22 has various measurement ranges depending on the magnitude of the current to be measured, but when measuring a minute current such as a static power supply leak current, the range close to that value is the optimum. When measuring in a large range, the accuracy is poor and accurate measurement is impossible.

As a result, when the pattern for internal setting is operated in a small measurement range to measure a minute current, it becomes an operating power supply current of the semiconductor integrated circuit device 21 to be measured, and a large current flows, so that the internal circuit operates normally. There is a problem that it is difficult to measure the leak current because the setting is not performed.

An object of the present invention is to solve the above-mentioned conventional problems, and to provide a method for measuring a leak current of a semiconductor integrated circuit device under test or the like which requires a large power supply current capacity for internal setting. That is.

[0011]

The measuring method of the present invention comprises:
The leak current of the semiconductor integrated circuit device under test is measured by connecting the resistor and the relay connected in parallel from the power supply unit of the LSI tester in series to the power supply terminal of the semiconductor integrated circuit device under test and the comparator of the LSI tester. It is a thing.

[0012]

According to the structure of the present invention, the voltage drop due to the product of the leak current and the resistance is compared with the voltage by the comparator to measure the leak current and determine whether the product is a good product or a defective product.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a method of measuring a static power supply leakage current according to an embodiment of the present invention.

In FIG. 1, 1 is an LSI tester, 2 is a semiconductor integrated circuit device under test, 3 is a relay, and 4 is a resistor. In the LSI tester, 5 is a power supply unit, 6 and 7 are comparators, 8 is a driver, and 9 is GN.
D is shown. In addition, 1 of the semiconductor integrated circuit device 2 under test is measured.
0 is a power supply terminal, 11 is an output terminal, 12 is an input terminal, 13
Indicates a GND terminal.

The method of measuring the static power supply leakage current thus configured will be described below. First, the relay 3 is turned on, and then the power supply unit 5 of the LSI tester 1 is set to a target applied voltage and applied. Here, the power supply unit 5 can supply a large current. Then LS
When the time-division pattern is input to the input terminal 12 of the semiconductor integrated circuit device 2 to be measured by the driver 8 of the I tester 1, at the same time, the internal state is time-divisionally output to the output terminal 11. While this output is being compared by the comparator 2 of the LSI tester 1, the internal setting for measuring the static power supply leakage current is completed.

Since the operating power supply current Idd flowing in this setting flows in the relay 3, the voltage drop due to this is almost zero. Therefore, the voltage applied to the power supply terminal 10 of the semiconductor integrated circuit device 2 to be measured becomes the set applied voltage of the power supply unit 5 of the LSI tester 1, and the power can be sufficiently supplied to realize the normal internal setting.

Next, the relay 3 is turned off when the internal setting is completed normally and the stationary state is entered.

When the relay 3 is turned off, the quiescent power supply leakage current Ids of the semiconductor integrated circuit device 2 under measurement flows through the resistor 4 to generate a voltage drop R × Ids. This voltage drop is LS
The comparator 1 of the I tester 1 makes a comparison to determine whether the product is a good product or a defective product.

[0020]

According to the measuring method of the present invention, the voltage drop due to the product of the resistance and the leak current flowing through the resistor connected in series to the power supply terminal of the device under test is compared by the comparator to determine the non-defective product. It is possible to realize a measuring method that determines whether the product is defective or defective.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a method for measuring a quiescent power source leakage current according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a conventional static power supply leakage current measuring method.

[Explanation of symbols]

 1 LSI tester 2 Semiconductor integrated circuit device under test 3 Relay 4 Resistance R

Claims (1)

[Claims] 1. A resistor and a relay connected in parallel from a power supply unit of an LSI tester are connected in series to a power supply terminal of a semiconductor integrated circuit device and a comparator of an LSI tester, and a product of a quiescent power supply leakage current and a main resistance. A method for measuring leak current, characterized in that the voltage drop due to voltage is compared by a comparator.