Voltage generator circuit and method for controlling thereof

A voltage generator circuit comprising:

• a voltage generator activated by a reference voltage to generate an output voltage;
• a reference voltage clamp circuit coupled to the voltage generator for clamping the reference voltage to a predetermined clamp voltage in response to a power-down signal to deactivate the voltage generator;
• and
• a sub-threshold current reduction circuit for reducing a sub-threshold current flowing into the voltage generator when the voltage generator is deactivated,
• wherein the output signal is supplied to an internal circuit of a semiconductor device, and the sub-threshold current reduction circuit includes a balance voltage setting circuit for setting a balance voltage at which the sub-threshold current flowing into the voltage generator balances a sub-threshold current flowing into the internal circuit.

A voltage generator circuit comprising:

• a voltage generator activated by a reference voltage to generate an output voltage, wherein the voltage generator includes a transistor having a gate and a back gate;
• a reference voltage clamp circuit coupled to the voltage generator for clamping the reference voltage to a predetermined clamp voltage in response to a power-down signal to deactivate the voltage generator;
• and
• a sub-threshold current shut-off circuit for shutting off generation of a sub-threshold current of the voltage generator by controlling a voltage directly applied to the back gate of the transistor of the voltage generator, and wherein the sub-threshold current shut-off circuit sets a predetermined clamp voltage at the gate of the transistor to a voltage at which the sub-threshold current can be shut off by controlling a voltage applied to the reference voltage clamp circuit.

A semiconductor device comprising:

• a voltage generator circuit including:
• a voltage generator activated by a reference voltage to generate an output voltage;
• a reference voltage clamp circuit coupled to the voltage generator for clamping the reference voltage to a predetermined clamp voltage in response to a power-down signal to deactivate the voltage generator;
• and
• a sub-threshold current reduction circuit including a resistor coupled between the voltage generator and one of a high potential power supply and a low potential power supply, wherein a resistance value of the resistor is at least 105Ω to maintain the output voltage to a value slightly higher than the voltage of the low potential power supply so that a sub-threshold current flowing into the voltage generator is reduced when the voltage generator is deactivated;
• and
• an internal circuit coupled to the voltage generator and enabled by the output voltage.