JPH11353036A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To highly accurately supply an internal power source voltage when tested and to suppress stress, which is applied to the internal circuit of a semiconductor device, equally with the time of ordinary operation. SOLUTION: By inserting an integration circuit 6 on an input path from an external terminal 1, even when an input voltage EVPI to be applied to the external terminal 1 at the time of testing the internal circuit of the semiconductor device has a steep waveform, the output of the integration circuit 6 becomes a dull waveform. Then, since the stress equal with the time of ordinary operation can be realized for the internal circuit of the semiconductor device and the input voltage EVPI of a fixed voltage value is highly accurately selected at the time of testing the internal circuit of the semiconductor device, the high- accuracy internal power source voltage can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device having an internal voltage generating circuit.

[0002]

2. Description of the Related Art A conventional semiconductor device will be described with reference to the drawings. FIG. 4 is a block diagram of a conventional semiconductor device.

In FIG. 4, reference numeral 1 denotes an external terminal connected to an external voltage applying device (not shown) for generating a DC voltage having a high accuracy and a constant voltage value, and 2 denotes a power supply device for a semiconductor device 5 (not shown). And an internal voltage generating circuit 3 for generating an internal voltage VG for the semiconductor device 5 from a power supply voltage VDD supplied via the external power supply terminal 2. One of the internal voltage VG generated by the internal voltage generating circuit 3 and the external input voltage EVPI having a constant voltage value applied via the external terminal 1 is selected by the selection circuit 4.
And output as the internal power supply voltage VPI.

The operation of the above configuration will be described. During the normal operation of the semiconductor device 5, the power supply voltage VDD is supplied to the external power supply terminal 2, and the output voltage VG of the internal voltage generation circuit 3 is selected by the selection circuit 4 and used as the internal power supply voltage VPI. However, the voltage value of the internal power supply voltage VPI does not become a constant value due to power supply voltage characteristics and temperature characteristics of the internal voltage generation circuit 3, production variations of the semiconductor device 5, and the like. Therefore, when testing the internal circuit of the semiconductor device, the selection circuit 4 selects the input voltage EVPI of a high-precision constant voltage input from the external terminal 1 and uses it as the internal power supply voltage VPI.

As described above, a highly accurate test can be performed by using the internal power supply voltage VPI as the high-precision input voltage EVPI supplied from the outside and having a constant voltage value.
FIG. 5 is a block diagram of the internal voltage generation circuit 3.

The internal voltage generation circuit 3 includes a reference voltage generation circuit 13 for generating an internal power supply voltage set value VK, and an internal power supply voltage set value VK generated by the reference voltage generation circuit 13.
A voltage comparison circuit 16 for outputting a result of voltage comparison with the internal power supply voltage VG output to the selection circuit 4;
And a voltage generation circuit 17 for generating an internal power supply voltage VG according to the output from the power supply.

With the above configuration, the internal power supply voltage set value VK generated by the reference voltage generation circuit 13 and the internal power supply voltage VG are compared by the voltage comparison circuit 16, and the voltage comparison between the internal power supply voltage VG and the internal power supply voltage set value is performed. The result is output to the voltage generation circuit 17, and the voltage generation circuit 17 raises or lowers the output voltage (internal power supply voltage VG) according to the input voltage comparison result. As a result, the internal power supply voltage VG is
Coincides with the set value of the internal power supply voltage at which the error occurs.

The reason why the output voltage VG generated by the internal voltage generating circuit 3 does not become a constant value is mainly because the output value of the reference voltage generating circuit 13 varies.

[0009]

In a conventional semiconductor device, the power supply voltage VDD is supplied to the external power supply terminal 2 during normal operation, whereby the internal voltage generating circuit 3 operates and a voltage is output. As shown in FIG.
The rise of the internal power supply voltage VPI with respect to the input of D has a dull waveform. However, when the input voltage EVPI of the external terminal 1 is set to the internal power supply voltage VPI during the test, FIG.
As shown in (b), since the input voltage EVPI of the external terminal 1 has a steep waveform supplied from the external voltage applying device, the rise of the internal power supply voltage VPI also becomes steep. If the rise of the internal power supply voltage VPI is steep unlike the normal operation, an excessive stress is applied to the internal circuit of the semiconductor device as compared with the normal operation, and there is a problem that a correct test cannot be performed. .

[0010] It is an object of the present invention to provide a semiconductor device capable of supplying an internal power supply voltage with high accuracy during a test and suppressing a stress applied to an internal circuit of the semiconductor device to the same level as in a normal operation. I do.

[0011]

In a semiconductor device according to the present invention, an integrating circuit is inserted on an input path from an external terminal.

According to the present invention, it is possible to obtain a semiconductor device capable of supplying a highly accurate internal power supply voltage during a test and suppressing a stress applied to an internal circuit of the semiconductor device to the same level as in a normal operation.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION
A semiconductor device having an internal voltage generation circuit, comprising: an external terminal connected to an external voltage application device that generates a voltage having a constant voltage value; and an integration circuit that integrates an external input voltage applied via the external terminal. A selection circuit that selects one of the output voltage of the integration circuit and the output voltage of the internal voltage generation circuit and outputs the selected output voltage as an internal power supply voltage. Even if the input voltage has a steep waveform, the output of the integrator circuit becomes a dull waveform, so that the same stress can be realized in the internal circuit of the semiconductor device as in the normal operation, and the internal circuit of the constant voltage value with high accuracy can be realized. It has the effect of being able to supply power supply voltage.

According to a second aspect of the present invention, there is provided an external terminal connected to an external voltage applying device for generating a voltage having a constant voltage value,
A reference voltage generation circuit, a selection circuit that selects and outputs one of an output reference voltage of the reference voltage generation circuit and an external reference voltage having a constant voltage value applied through the external terminal, and an output voltage of the selection circuit. A voltage comparison circuit that outputs a voltage comparison result between the internal power supply voltage and the internal power supply voltage, and a voltage generation circuit that generates the internal power supply voltage in accordance with the output of the voltage comparison circuit. By selecting an external reference voltage having a high-precision constant voltage value applied from the outside as a reference voltage, the reference voltage becomes a constant value, so that the internal power supply voltage can be kept constant. This has the effect that no stress different from that during operation is applied.

An embodiment of the present invention will be described below with reference to the drawings. The same components as those of the conventional example shown in FIGS. 4 and 5 are denoted by the same reference numerals, and description thereof is omitted. (First Embodiment) FIG. 1 is a block diagram of a semiconductor device according to a first embodiment.

In the first embodiment, the external terminal 1 is connected to an integrating circuit 6 for integrating an external input voltage having a constant voltage value with high precision applied through the external terminal 1. One of output voltage VS of integrating circuit 6 and output voltage VG of internal voltage generating circuit 3 is selected, and internal power supply voltage VP
It is output as I.

The operation of the above configuration will be described. During normal operation of the semiconductor device 5, the power supply voltage VDD is supplied to the external power supply terminal 2, and the output voltage VG of the internal voltage generation circuit 3 is selected by the selection circuit 4 and used as the internal power supply voltage VPI.
However, the voltage value of the internal power supply voltage VPI does not become a constant value due to power supply voltage characteristics and temperature characteristics of the internal voltage generation circuit 3, production variations of the semiconductor device 5, and the like. Therefore, when testing the internal circuit of the semiconductor device, the integration circuit 6 integrates the input voltage EVPI of a high-precision constant voltage applied to the external terminal 1, selects the output voltage VS by the selection circuit 4, and sets the output voltage VS as the internal power supply voltage VPI. use.

As described above, when the internal circuit of the semiconductor device is tested, a highly accurate input voltage EVPI supplied from the outside and having a constant voltage value becomes the internal power supply voltage VPI. Even if the input voltage EVPI supplied to 1 has a steep waveform, the output voltage VS (internal power supply voltage VPI) of the integration circuit 6 becomes blunt, as shown in FIG. The same stress as in normal operation can be realized for the circuit.

Second Embodiment FIG. 3 is a block diagram of a semiconductor device according to a second embodiment. Instead of the conventional internal voltage generating circuit 3, a reference voltage generating circuit 13 for generating a reference voltage as an internal power supply voltage set value is provided.
The output voltage (internal power supply voltage setting value) VK of this reference voltage generating circuit 13 and the external input voltage (internal power supply voltage setting value input from outside) of a high-precision constant voltage value applied via external terminal 1 EXT Is selected and output.

A voltage comparison circuit 16 for outputting a voltage comparison result between the output voltage of the selection circuit 4 (the set value of the selected internal power supply voltage) and the internal power supply voltage VPI, and a voltage comparison circuit 16
Is provided with a voltage generating circuit 17 for generating an internal power supply voltage VPI in accordance with the output of.

The operation of the above configuration will be described. During normal operation, the internal power supply voltage set value VK output from the reference voltage generation circuit 13 is output from the selection circuit 14, and the internal power supply voltage set value and the internal power supply voltage VPI are compared by the voltage comparison circuit 16, and the internal power supply voltage VPI is The result of the voltage comparison with the set value of the internal power supply voltage is output to the voltage generation circuit 17, and the voltage generation circuit 17
Raises or lowers the output voltage (internal power supply voltage VPI) according to the input voltage comparison result. As a result, internal power supply voltage VPI matches the internal power supply voltage set value output by reference voltage generation circuit 13.

During the test of the internal circuit of the semiconductor device, the internal power supply voltage set value EXT of a high-precision constant voltage value from the external terminal 1 is output from the selection circuit 4, and the internal power supply voltage VPI
Is compared by the voltage comparison circuit 16, and the result of the voltage comparison between the internal power supply voltage VPI and the internal power supply voltage set value EXT is output to the voltage generation circuit 17. The voltage generation circuit 17 outputs the output voltage ( The internal power supply voltage VPI is increased or decreased. As a result, the internal power supply voltage VPI matches the internal power supply voltage set value EXT of a constant voltage value with high accuracy from the external terminal 1.

As described above, when the internal circuit of the semiconductor device is tested, the internal power supply voltage set value EXT having a high precision and constant voltage supplied from the outside becomes the reference voltage of the internal power supply voltage VPI, so that the reference voltage becomes constant. Thus, the internal power supply voltage VPI can be set to a high-precision constant voltage value, so that a high-precision test can be performed. Further, even if the internal power supply voltage set value EXT supplied to the external terminal 1 has a steep waveform, no stress different from that in the normal operation is applied to the internal circuit of the semiconductor device, and the internal circuit of the semiconductor device is not applied to the internal circuit. Can achieve the same stress as in normal operation.

[0024]

As described above, according to the present invention, even when a steep waveform is input to the external terminal, the same stress as in the normal operation can be realized in the internal circuit of the semiconductor device, and the internal power supply with high accuracy can be realized. An advantageous effect that voltage supply can be realized is obtained.

[Brief description of the drawings]

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

FIG. 2 is a generation waveform diagram of an internal power supply voltage due to an external terminal voltage input of the semiconductor device.

FIG. 3 is a block diagram of a semiconductor device according to a second embodiment of the present invention.

FIG. 4 is a block diagram of a conventional semiconductor device.

FIG. 5 is a block diagram of an internal voltage generation circuit of a conventional semiconductor device.

FIG. 6 is a diagram showing a waveform of an internal power supply voltage generated by an internal voltage generation circuit of a conventional semiconductor device and a waveform of an internal power supply voltage generated by input of an external terminal voltage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 External terminal 2 External power supply terminal 3 Internal voltage generation circuit 4 Selection circuit 5 Semiconductor device 6 Integrator circuit 13 Reference voltage generation circuit 16 Voltage comparison circuit 17 Voltage generation circuit EVPI Input voltage from external voltage application device EXT Internal power supply voltage set value ( Reference voltage) VG Output voltage of internal voltage generation circuit VK Internal power supply voltage set value (reference voltage) VPI Internal power supply voltage VS Output voltage of integration circuit

Claims (2)

[Claims] 1. A semiconductor device having an internal voltage generating circuit, comprising: an external terminal connected to an external voltage applying device for generating a voltage having a constant voltage value; and an external input voltage applied via the external terminal. A semiconductor device comprising: an integration circuit for integrating; and a selection circuit for selecting one of an output voltage of the integration circuit and an output voltage of the internal voltage generation circuit and outputting the selected voltage as an internal power supply voltage. 2. An external terminal connected to an external voltage applying device for generating a voltage having a constant voltage value, a reference voltage generating circuit, an output reference voltage of the reference voltage generating circuit, and an external terminal. A selection circuit that selects and outputs one of the external reference voltages, a voltage comparison circuit that outputs a voltage comparison result between an output voltage of the selection circuit and an internal power supply voltage, and an internal power supply that responds to an output of the voltage comparison circuit A semiconductor device comprising a voltage generating circuit for generating a voltage.