Regulator circuit and semiconductor integrated circuit device
A regulator circuit includes a first transistor reducing an external supply voltage and outputting an internal active voltage to an output node; a first detector receiving a criteria level, detecting the internal active voltage based on an enable signal, controlling a gate voltage of the first transistor, and adjusting an output current thereof; a second transistor reducing the external supply voltage, and outputting an internal standby voltage corresponding to the internal active voltage to the output node; a second detector receiving a reference voltage, detecting the internal standby voltage regardless of the enable signal, controlling a gate voltage of the second transistor, and adjusting an output current thereof; a first switch controlling whether to output the reference voltage as the criteria level of the first detector; and a second switch controlling whether to output the voltage of the output node as the criteria level of the first detector.
1. A regulator circuit comprising:
a first transistor of a first conductivity type configured to reduce an external supply voltage and output an internal active voltage to an output node;
a first detector configured to receive a criteria level, detect the internal active voltage based on a state of an enable signal, control a gate voltage of the first transistor, and adjust an output current of the first transistor;
a second transistor of the first conductivity type configured to reduce the external supply voltage, and output an internal standby voltage corresponding to the internal active voltage to the output node;
a second detector configured to receive a reference voltage, detect the internal standby voltage regardless of the state of the enable signal, control a gate voltage of the second transistor, and adjust an output current of the second transistor;
a first switch configured to control whether to output the reference voltage as the criteria level of the first detector; and
a second switch configured to control whether to output the voltage of the output node as the criteria level of the first detector.
2. The regulator circuit according to claim 1 , wherein the first switch is a first CMOS transfer gate, and
the second switch is a second CMOS transfer gate.
3. The regulator circuit according to claim 1 , wherein
when the enable signal is placed in a first state,
the first detector is inactivated and the internal standby voltage from the second transistor is output to the output node, and
when the enable signal is placed in a second state,
the first detector is activated and the internal active voltage from the first transistor and the internal standby voltage from the second transistor are output to the output node.
4. The regulator circuit according to claim 3 , wherein the first detector includes:
a first terminal configured to receive the voltage of the output node; and
a second terminal configured to receive the criteria level, and wherein
when the enable signal is placed in the second state, the activated first detector compares the levels of the first terminal and the second terminal and adjusts the output amount of the first transistor.
5. The regulator circuit according to claim 3 , the regulator circuit further comprising a first switch control circuit configured to control on/off of the first switch and the second switch, wherein
when the enable signal is placed in the first state, the first switch control circuit turns off the first switch, turns on the second switch, and applies the internal standby voltage as the criteria level so as to keep a standby state, and
when the enable signal changes from the first state to the second state, the first switch control circuit turns off both of the first switch and the second switch after a specified delay, and subsequently the first switch control circuit turns on the first switch, turns off the second switch, and applies the reference voltage as the criteria level so as to activate the first detector.
6. The regulator circuit according to claim 1 , the regulator circuit further comprising:
a reference voltage generating circuit configured to generate the reference voltage; and
a reference voltage holding capacitor configured to hold the generated reference voltage.
7. The regulator circuit according to claim 1 , the regulator circuit further comprising:
an internal voltage holding capacitor that holds the voltage of the output node; and
a current load that prevents an excessive change of the potential of the output node.
8. The regulator circuit according to claim 1 , wherein
the first transistor of the first conductivity type is a first p-channel MOS transistor, and
the second transistor of the first conductivity type is a second p-channel MOS transistor.
9. A regulator circuit comprising:
a first transistor of a first conductivity type configured to reduce an external supply voltage and output an internal active voltage to an output node;
a first detector configured to receive a criteria level, detect the internal active voltage based on a state of an enable signal, control a gate voltage of the first transistor, and adjust an output current of the first transistor;
a second transistor of the first conductivity type configured to reduce the external supply voltage, and output an internal standby voltage corresponding to the internal active voltage to the output node;
a second detector configured to receive a reference voltage, detect the internal standby voltage regardless of the state of the enable signal, control a gate voltage of the second transistor, and adjust an output current of the second transistor; and
a third switch configured to control whether to output the internal standby voltage to the output node, wherein
the internal standby voltage is input as the standard potential of the first detector.
10. The regulator circuit according to claim 9 , wherein the third switch is a third CMOS transfer gate with one end connected to the output node and the other end receiving the internal standby voltage.
11. The regulator circuit according to claim 9 , wherein
when the enable signal is placed in a first state,
the first detector is inactivated and the internal standby voltage from the second transistor is output to the output node, and
when the enable signal is placed in a second state,
the first detector is activated and the internal active voltage from the first transistor is output to the output node.
12. The regulator circuit according to claim 11 , wherein the first detector includes:
a first terminal that receives the voltage of the output node; and
a second terminal that receives the internal standby voltage, and wherein
when the enable signal is placed in the second state, the activated first detector compares the levels of the first terminal and the second terminal and adjusts the output amount of the first transistor.
13. The regulator circuit according to claim 11 , the regulator circuit further comprising a second switch control circuit that controls on/off of the third switch, wherein
when the enable signal is placed in the first state, the second switch control circuit turns on the third switch and outputs the internal standby voltage to the output node so as to keep a standby state, and
when the enable signal changes from the first state to the second state, the second switch control circuit turns off the third switch after a specified delay, and subsequently the second switch control circuit isolates the internal standby voltage from the output node and applies the internal standby voltage only as the criteria level so as to activate the first detector.
14. The regulator circuit according to claim 9 , the regulator circuit further comprising:
a reference voltage generating circuit configured to generate the reference voltage; and
a reference voltage holding capacitor configured to hold the generated reference voltage.
15. The regulator circuit according to claim 9 , the regulator circuit further comprising:
an internal voltage holding capacitor that holds the voltage of the output node; and
a current load that prevents an excessive change of the potential of the output node.
16. The regulator circuit according to claim 9 , wherein
the first transistor of the first conductivity type is a first p-channel MOS transistor, and
the second transistor of the first conductivity type is a second p-channel MOS transistor.
17. A semiconductor integrated circuit device comprising:
a regulator circuit; and
an internal circuit where the voltage of the output node of the regulator circuit is used, wherein
the regulator circuit comprises:
a first transistor of a first conductivity type configured to reduce an external supply voltage and output an internal active voltage to an output node;
a first detector configured to receive a criteria level, detect the internal active voltage based on a state of an enable signal, control a gate voltage of the first transistor, and adjust an output current of the first transistor;
a second transistor of the first conductivity type configured to reduce the external supply voltage, and output an internal standby voltage corresponding to the internal active voltage to the output node;
a second detector configured to receive a reference voltage, detect the internal standby voltage regardless of the state of the enable signal, control a gate voltage of the second transistor, and adjust an output current of the second transistor;
a first switch configured to control whether to output the reference voltage as the criteria level of the first detector; and
a second switch configured to control whether to output the voltage of the output node as the criteria level of the first detector.
18. The semiconductor integrated circuit device according to claim 17 , wherein the internal circuit is a memory circuit or a logic circuit.