JP3106486B2 - Measurement equipment for semiconductor integrated circuits - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring device for a semiconductor integrated circuit, and more particularly to a power supply circuit of a built-in comparator circuit.

[Conventional technology]

Conventionally, this type of semiconductor integrated circuit (hereinafter referred to as IC)
As shown in FIG. ₂ , the output voltage B ₁ , B ₂ , of the power supply circuit 21 of the IC dedicated test apparatus 3 is connected to the power supply terminals V ₁ , V ₂ , V ₃ , V ₄ of the device under test IC ₁ as shown in FIG. B _3, B ₄ of the voltage is applied, the output terminals S _1, S ₂ ~S IC dedicated testing device a voltage output from the _n 3 of the measured IC ₁
Connect was measured of the comparator circuit C _1, C ₂ ~C _n.

The configuration of the IC dedicated test apparatus 3 is a power supply circuit 21 for the IC _{1 to} be measured.
When the comparator circuit C _1, C ₂ ~C _n, the power supply circuit D ₁ to set the comparison voltage Ref _1, Ref ₂ ~Ref _n of comparator circuit, D ₂ ~
D _n and a power supply 22.

Power circuit 21, D _1, D ₂ output voltage of _{~D n B 1 ~B 4, VO} 1, VO 2 ~VO
_n is the voltage data 1, voltage data E ₁ , E ₂ to
Set in E _n, also the power supply 22 is a comparator circuit C _1, C ₂ ~C
_n and the power supply circuit D _1, a power source of D ₂ to D _n.

An example of the voltage waveform outputted from the output terminal S _1, S ₂ ~S _n of the measured IC ₁ shown in FIG. 3.

The method of measuring the voltage values of the output terminals S _1, S ₂ ~S _n of the measured IC with IC dedicated test apparatus 3 shown below. To measure the voltage of the output terminal S _{1 of the} IC under test S ₁ = 10 V, the output voltage VO ₁ of the power supply circuit D ₁ is set to 11 V. This voltage of VO ₁ = 11 V is input as the comparison voltage Ref ₁ of the comparator circuit C1. Comparator circuit C ₁ compares the magnitude of the output terminal S ₁ = 10V of Ref ₁ = 11V and the measured IC _1. The determination result of the comparator circuit C ₁ becomes smaller than the comparison voltage Ref _1. Since the determination result of the comparator circuit C ₁ becomes small, in turn, the output voltage of the power supply circuit D ₁
VO ₁ = 9V. As before, the magnitude of this VO ₁ = the voltage of 9V at the comparator circuit compares the voltage Ref ₁ and inputted to the comparator circuit C ₁ of C _1, Ref ₁ = 9V output terminal S ₁ = 10V of the measured IC ₁ when comparing the judgment result of the comparator circuit C ₁ is larger than the comparison voltage Ref _1. As described above, the comparator circuit C ₁ is changed by changing the comparison voltage Ref ₁ of the comparator circuit.
Measures the voltage value of the output terminal S ₁ of the measured IC ₁ from the result of the determination.

The measurement is performed in the same manner for other output voltage values of 20V, 30V, and 40V. V _SS power supply circuit _{21, D 1, D 2 ~D} n has a all common to the GND potential.

Comparator circuit C ₁ of the current IC dedicated test device, C ₂ -C _n
And the voltage range of the power supply circuit _{21, D 1, D 2 ~D} n is about 0 to 20V, IC dedicated output voltage of 30V or 40V from the output terminal S _1, S ₂ ~S _n of the measured IC ₁ When the measurement is to be performed by the comparator circuit of the test apparatus 3, the comparator circuits C ₁ and C _2
If the operating voltage range of ~ Cn is 20V and the input voltages are 30V and 40V, comparison becomes impossible.

[Problems to be solved by the invention]

At present, liquid crystal driving ICs are required to have a higher voltage for driving the liquid crystal and an increase in the number of terminals for driving the liquid crystal.Therefore, a dedicated IC testing device having a large number of comparator circuits and power supply circuits capable of simultaneously measuring a high voltage is required. I need. However, in the above-described conventional measuring apparatus, only the comparator circuit and the power supply circuit whose limits are about 0 to 22 V are built in.
There is a problem that measurement of a high-voltage liquid crystal driving IC requiring a voltage of 50 V or the like cannot be performed by a conventional IC-dedicated test apparatus.

In addition, providing a high-voltage comparator circuit and a power supply circuit at each measurement terminal as a new measurement device is an extremely expensive IC considering the increase in the number of output terminals of the liquid crystal drive IC.
There was a problem that it became a dedicated test device.

An object of the present invention is to provide a measuring device for a semiconductor integrated circuit which can measure a high voltage liquid crystal driving IC.

[Means for solving the problem]

In order to achieve the above object, a semiconductor integrated circuit measurement device according to the present invention is a semiconductor integrated circuit measurement device including a voltage power supply circuit, a comparator circuit, and a comparison voltage generation power supply circuit of the comparator circuit. The power supply potential of the comparator circuit and the power supply potential of the comparison voltage generation power supply circuit of the comparator circuit are varied by the voltage power supply circuit.

[Action]

The power supply (V _DD and V _SS ) potentials of the comparator circuit built in the IC dedicated test apparatus and the power supply potential of the comparison voltage generating power supply circuit of the comparator are changed by the voltage power supply circuit of the IC dedicated test apparatus.

〔Example〕

 Next, the present invention will be described with reference to the drawings.

 FIG. 1 is a block diagram showing one embodiment of the present invention.

In the figure, output voltages B ₁ , B ₂ , B ₃ , B ₄ of the voltage power supply circuit 21 of the IC dedicated test apparatus 3 are input terminals V ₁ , V ₂ , V ₃ , V _{3 of} the IC _{1 to} be measured.
Connected to ₄ . In addition, output terminals S ₁ and S _{2 of} IC _{1 to} be measured
SS _n are the comparator circuits C ₁ , C ₂ CC of the IC dedicated test apparatus 3.
Connected to _n .

Configuration of IC dedicated test device 3 includes a voltage supply circuit 21, a comparator circuit C _1, C ₂ ~C _n and a power supply circuit D ₁ of the order to set the comparison voltage _{Ref 1, Ref 2 ~Ref n,} D 2 ~ It is constituted by a D _n.

The voltage power supply circuit 21 of the IC-dedicated test apparatus 3 is a power supply circuit capable of setting a voltage substantially equal to the liquid crystal drive voltage.
The power supply circuit D _1, D ₂ ~D _n is a power circuit capable of setting 0 to 20V. Output voltage of voltage power supply circuit 21 of IC-dedicated test equipment 3
B _{1 to} B ₆ can be set by the voltage data 1 of the IC dedicated test apparatus. Similarly the power supply circuit D _1, D ₂ ~D _n of the output voltage V
O _1, VO ₂ ~VO voltage data E ₁ of _n also IC dedicated testing device 3, E ₂ to E _n
Can be set. The power supply V _DD , V _SS potentials of the comparator circuits C ₁ , C _{2 to} C _n of the IC dedicated test apparatus 3 can be set by the output voltages B ₅ , B ₆ of the voltage power supply circuit 21 of the IC dedicated test device. In addition, the power supply circuits D ₁ , D ₂
To D _n of the power supply V _DD, V _SS potential can also be set by the output voltage B _5, B ₆ of the IC dedicated test apparatus 3 of the voltage supply circuit 21.

Each voltage of the output terminal S _1, S ₂ ~S _n of the measured IC ₁ of this embodiment
The method for measuring with an IC dedicated test device is shown below.

The output of the voltage power supply circuit 21 of the IC dedicated test apparatus 3 is B ₁ = 10
_{V, B 2 = 20V, B} 3 = 30V, set B ₄ = 40V, V ₁ to be measured IC _{1
= 10V, V 2 = 20V,} V 3 = 30V, the case of applying V ₄ = 40V, the output terminal S _1, S ₂ ~S _n of the measured IC ₁ ', the voltage of 10V~40V occurs. In this case, for example, S ₁ to the output terminal of the measured IC ₁
= 40V, S ₂ = 10V, and S _n = 10V are output, and to measure S ₁ = 40V, first, the output voltage B ₅ of the voltage power supply circuit 21 = 50V,
When B ₆ is set to 30 V, the power supply of the comparator circuits C ₁ , C _{2 to} C _n is V _DD = 50 V, V _SS 30 V, and the power supply of the power supply circuits D ₁ , D _{2 to} D _n is V
_DD = 50V and VSS = 30V. Next, when the voltage data of the power supply circuit D ₁ is set to 11V, since V _SS potential of the power supply circuit D ₁ is 30 V, 41V is output to the output voltage VO ₁ of the power supply circuit D _1. Comparison voltage of VO ₁ = a voltage of 41V comparator circuit C ₁ RefV
Enter ₁ Comparator circuit C ₁ compares the magnitude of the Ref ₁ = 40V and the output terminal S ₁ = 40V of the measured IC _1. The determination result of the comparator circuit C ₁ becomes smaller than the comparison voltage Ref _1.
Since the determination result of the comparator circuit C ₁ becomes small, the future, setting the voltage data of the power supply circuit D ₁ to 9V. Power circuit
39V is output to the voltage VO ₁ of D _1. VO ₁ = 3 as before
Ref ₁ = 39V and the output terminal of the measured IC ₁ by the comparator circuit C ₁ apply voltage of 9V in comparison voltage Ref ₁ of the comparator circuit C ₁
Compare the magnitude with S ₁ = 40V. For now, the judgment result of the comparator circuit C ₁ is larger than the reference voltage Ref _1.
By changing the output voltage VO ₁ of the power supply circuit D ₁ as described above, S ₁
Measure the voltage value of

Although an example of a measurement of the output terminal S ₁ = 40V of the measured IC _1,
Other voltage 30 V, 20V, similarly in the case of 10V, suit the comparison voltage to the value of each output by changing the output voltage of B _5, B _6.

Shows the relationship between the output voltage B ₁ .about.B ₆ and a power supply circuit D _1, D ₂ ~D _n of the output voltage of the output voltage and the voltage supply circuit 21 of the measured IC in Figure 4.

〔The invention's effect〕

As described above, the measuring apparatus of the present invention uses the power supply potential (VDD and V _SS ) of the comparator circuit of the IC dedicated test apparatus and the power supply potential of the comparison voltage generating power supply circuit of the comparator circuit as the voltage power supply circuit of the IC dedicated test apparatus. Has the effect that the comparator circuit and the power supply circuit for comparator comparison voltage can easily be measured in the conventional voltage range.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional example, and FIG. 3 is an output terminal of an IC to be measured.
S _1, S ₂ ~S _n diagram showing an example of an output voltage waveform of Figure 4 is the output voltage B ₁ .about.B ₆ and a power supply circuit of the output voltage and the voltage supply circuit 21 of the measured IC in the embodiment of the present invention D _1, a diagram illustrating the relationship between the output voltage of the D ₂ to D _n. 1 ...... the measured IC, 3 ...... IC dedicated testing device _{V 1, V 2, V 3} , V 4 ...... input terminal S ₁ of the measured IC, S ₂ to S _n ...... output terminal D of the measured IC ₁ , D _{2 to} D _n … Comparative voltage power supply circuit of IC dedicated test equipment C ₁ , C _{2 to} C _n … Comparator circuit of IC dedicated test equipment 21 …… Voltage power supply circuit of IC dedicated test equipment

Claims (1)

(57) [Claims] 1. An apparatus for measuring a semiconductor integrated circuit comprising a voltage power supply circuit, a comparator circuit, and a power supply circuit for generating a comparison voltage of the comparator circuit, wherein a power supply potential of the comparator circuit and a comparison voltage generation of the comparator circuit are generated. A power supply potential of a power supply circuit is varied by the voltage power supply circuit.