Semiconductor integrated circuit

A semiconductor integrated circuit, adapted for receiving a chip selection signal, comprising:

• an internal circuit having a node;
• first means for receiving a supply voltage;
• second means for receiving a second voltage;
• voltage detecting means for detecting a value of the supply voltage to generate a control signal;
• first voltage stepdown means for operating in one of
• a first mode for stepping down the supply voltage to apply a voltage to the node while conducting a first amount of current through the second receiving means, and
• a second mode while conducting an amount of current less than the first amount of current through the second receiving means, the first voltage step down means operating in either the first mode or in the second mode in response to the control signal and the chip selection signal;
• second voltage stepdown means for operating in one of
• a first mode for stepping down the supply voltage to apply a voltage to the node while conducting a first amount of current through the second receiving means, and
• a second mode while conducting an amount of current less than the first amount of current through the second receiving means, the second voltage step down means operating in either the first mode or in the second mode in response to the control signal;
• and
• means, coupled between the first receiving means and the node and responsive to the voltage detecting means, for selectively applying a voltage to the node at times when the first and second voltage stepdown means are both operating in the second mode.

A semiconductor integrated circuit, adapted for receiving a chip selection signal, comprising:

• an internal circuit having a node;
• first means for receiving a power supply voltage;
• second means for receiving a reference voltage;
• voltage detecting means for detecting a value of the supply voltage to generate a first control signal to indicate whether the value of the supply voltage is less than a first predetermined value and a second control signal to indicate whether the value of the supply voltage is less than a second predetermined value;
• first voltage stepdown means for operating in one of
• a first mode for stepping down the supply voltage to apply a voltage to the node while conducting a first amount of current through the second receiving means, and
• a second mode while conducting an amount of current less than the first amount of current through the second receiving means, the first voltage stepdown means operating in either the first mode or in the second mode in response to the first control signal and the chip selection signal;
• second voltage stepdown means for operating in one of
• a first mode for stepping down the supply voltage to apply a voltage to the node while conducting a first amount of current through the second receiving means, and
• a second mode while conducting an amount of current less than the first amount of current through the second receiving means, the second voltage stepdown means operating in either the first mode or in the second mode in response to the first control signal;
• and
• means, coupled between the first receiving means and the node and responsive to the second control signal, for selectively applying a voltage to the node in response to the second control signal.

A method of operating a semiconductor integrated circuit device having first means for receiving a supply voltage, second means for receiving a second voltage, a first circuit having a node, a second circuit capable of being activated to regulate a voltage applied to the node while conducting a first amount of current through the second means and capable of being deactivated to conduct an amount of current less than the first amount through the second means, and a switch coupled between the first means and the node, the method comprising the steps of:

• activating the second circuit;
• detecting a value of the supply voltage;
• deactivating the second circuit at times when the detecting step detects that the value of the supply voltage is less than a first predetermined value;
• and
• closing the switch at times when the detecting step detects that the value of the supply voltage is less than a second predetermined value.

A method of operating a semiconductor integrated circuit device, adapted to receive a selection signal, having first means for receiving a supply voltage, second means for receiving a second voltage, a first circuit having a node, a second circuit capable of being activated to regulate a voltage applied to the node while conducting an amount of current through the second means and capable of being deactivated to conduct another amount of current, less than the amount conducted by the second circuit when the second circuit is activated, through the second means, a third circuit capable of being activated to regulate a voltage applied to the node while conducting an amount of current through the second means and capable of being deactivated to conduct another amount of current, less than the amount conducted by the third circuit when the third circuit is activated, through the second means, and a switch coupled between the first means and the node, the method comprising the steps of:

• activating the second circuit in response to the selection signal;
• activating the third circuit;
• detecting a value of the supply voltage;
• deactivating the second circuit in response to the selection signal;
• deactivating the second and third circuits at times when the detecting step detects that the value of the supply voltage is less than a first predetermined value;
• and
• closing the switch at times when the detecting step detects that the value of the supply voltage is less than a second predetermined value.

A semiconductor integrated circuit device comprising:

• first means for receiving a supply voltage;
• second means for receiving a second voltage;
• a first circuit having a node;
• a second circuit capable of being activated to regulate a voltage applied to the node while conducting a first amount of current through the second means and capable of being deactivated to conduct an amount of current less than the first amount through the second means;
• means for deactivating the second circuit at times when the value of the supply voltage is less than a first predetermined value;
• and
• means for making an electrical connection between the first means and the node at times when the second circuit is deactivated.

A semiconductor integrated circuit device, adapted to receive a selection signal, comprising:

• first means for receiving a supply voltage;
• second means for receiving a second voltage;
• a first circuit having a node;
• a second circuit capable of being activated to regulate a voltage applied to the node while conducting an amount of current through the second means and capable of being deactivated to conduct another amount of current, less than the amount conducted by the second circuit when the second circuit is activated, through the second means, the second circuit being deactivated in response to the selection signal;
• a third circuit capable of being activated to regulate a voltage applied to the node while conducting an amount of current through the second means and capable of being deactivated to conduct another amount of current, less than the amount conducted by the third circuit when the third circuit is activated, through the second means;
• means for deactivating the second and third circuits at times when the value of the supply voltage is less than a first predetermined value;
• and
• means for making an electrical connection between the first means and the node at times when the second and third circuits are both deactivated.