US 5,694,364 AGranted

Semiconductor integrated circuit device having a test mode for reliability evaluation

AssigneeMitsubishi Denki Kabushiki Kaisha

InventorsFukashi Morishita, Masaki Tsukude, Kazutami Arimoto

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Abstract

In the normal mode, a first voltage-down converter down-converts an external power supply voltage to provide a large, first internal power supply voltage to the peripheral circuitry via a first internal power supply voltage supplying line, and a second voltage-down converter down-converts the external power supply voltage to provide a smaller, second internal power supply voltage to a memory cell array via a second internal power supply voltage supplying line. This allows fast operation and reduction in power consumption. In conducting a burn-in test, an external power supply voltage supplying line is connected to the first and second internal power supply voltage supplying lines. Thus, the first and second internal power supply voltage supplying lines directly receive the external power supply voltage. This allows an effective burn-in test. In a burn-in test, the first and second voltage-down converters are inactivated.

Claims15

Dependent claims

A semiconductor integrated circuit device having a test mode for reliability evaluation and a normal mode, said semiconductor integrated circuit device comprising:

first internal power supply voltage generating means for generating a first internal power supply voltage to be supplied on a first internal power supply voltage supplying line according to an external power supply voltage supplied from an external power supply voltage supplying line;
second internal power supply voltage generating means for generating a second internal power supply voltage to be supplied on a second internal power supply voltage supplying line according to said external power supply voltage;
first connecting means provided between said external power supply voltage supplying line and said first internal power supply voltage supplying line;
and
second connecting means provided between said external power supply voltage supplying line and said second internal power supply voltage supplying line;
wherein
said first and second internal power supply voltage generating means are inactivated in said test mode and are activated in said normal mode,
said first connecting means connects said external power supply voltage supplying line to said first internal power supply voltage supplying line in said test mode and disconnects said external power supply voltage supplying line from said first internal power supply voltage supplying line in said normal mode, and
said second connecting means connects said external power supply voltage supplying line to said second internal power supply voltage supplying line in said test mode and disconnects said external power supply voltage supplying line from said second internal power supply voltage supplying line in said normal mode.

6 more elements

A semiconductor integrated circuit device having a test mode for reliability evaluation and a normal mode, said semiconductor integrated circuit device comprising:

first internal power supply voltage generating means for generating a first internal power supply voltage to be supplied on a first internal power supply voltage supplying line according to a first external power supply voltage supplied from a first external power supply voltage supplying line;
second internal power supply voltage generating means for generating a second internal power supply voltage to be supplied on a second internal power supply voltage supplying line according to said first external power supply voltage supplied from a second external power supply voltage supplying line;
first connecting means provided between said first external power supply voltage supplying line and said first internal power supply voltage supplying line;
and
second connecting means provided between said second external power supply voltage supplying line and said second internal power supply voltage supplying line;
wherein
said first and second internal power supply voltage generating means are inactivated in said test mode and are activated in said normal mode;
said first connecting means connects said first external power supply voltage supplying line to said first internal power supply voltage supplying line in said test mode and disconnects said first external power supply voltage supplying line from said first internal power supply voltage supplying line in said normal mode;
said second connecting means connects said second external power supply voltage supplying line to said second internal power supply voltage supplying line in said test mode, and disconnects said second external power supply voltage supplying line form said second internal power supply voltage supplying line in said normal mode;
in said test mode, said first external power supply voltage supplying line receives a second external power supply voltage and said second external power supply voltage supplying line receives a third external power supply voltage having a level different from that of said second external power supply voltage;
and
in said normal mode, said first and second external power supply voltage supplying lines receive said first external power supply voltage.

9 more elements

A semiconductor integrated circuit device having a test mode for reliability evaluation and a normal mode, said semiconductor integrated circuit device comprising:

first internal power supply voltage generating means for generating a first internal power supply voltage to be supplied on a first internal power supply voltage supplying line according to an external power supply voltage supplied from an external power supply voltage supplying line;
second internal power supply voltage generating means for generating a second internal power supply voltage to be supplied on a second internal power supply voltage supplying line according to said external power supply voltage;
first connecting means provided between said external power supply voltage supplying line and said first internal power supply voltage supplying line;
second connecting means provided between said external power supply voltage supplying line and an intermediate node;
and
down-converting means provided between said intermediate node and said second internal power supply voltage supplying line;
wherein
said first and second internal power supply voltage generating means are inactivated in said test mode and are activated in said normal mode;
said first connecting means connects said external power supply voltage supplying line to said first internal power supply voltage supplying line in said test mode and disconnects said external power supply voltage supplying line from said first internal power supply voltage supplying line in said normal mode;
said second connecting means connects said external power supply voltage supplying line to said intermediate mode in said test mode and disconnects said external power supply voltage supplying line from said intermediate node in said normal mode;
and
said down-converting means supplies a voltage down-converted from said external power supply voltage to said second internal power supply voltage supplying line in said test mode.

9 more elements

A semiconductor integrated circuit device having a test mode for reliability evaluation and a normal mode, said semiconductor integrated circuit device comprising:

a plurality of memory cells arranged in a matrix of rows and columns;
a plurality of word lines each arranged corresponding to each of the rows and each having corresponding said memory cells connected thereto;
a plurality of driver means each provided corresponding to each of the word lines;
test voltage supplying means for supplying a first test voltage according to an external power supply voltage to each of said driver means via a voltage supplying line in said test mode;
and
boosted voltage generating means for generating a boosted voltage and supplying said boosted voltage to said driver means in said normal mode;
wherein
in said normal mode, said driver means corresponding to a selected said word line applies a voltage to the corresponding said word line according to said boosted voltage, and
in said test mode, each said driver means applies a voltage to a corresponding said word line according to said first test voltage, and wherein
said test voltage supplying means includes current limiting means for limiting a current flowing into said voltage supplying line.

7 more elements

Dependencies are inferred from the claim text.