Semiconductor device having internal voltage generating circuit
A semiconductor device including a first internal voltage generating circuit that includes a capacitor including a first electrode and a second electrode, and the first internal voltage generating circuit to generate an internal voltage by charging the capacitor to a first voltage and applying a second voltage to the first electrode of the capacitor to generate a third voltage that is greater than the first and the second voltages on the second electrode in absolute value, and a control circuit to perform a control by applying a fourth voltage that is less than the first voltage to the capacitor when the first internal voltage generating circuit is in a standby state.
1. A semiconductor device comprising:
a first power supply line configured to supply a first voltage;
a second power supply line configured to supply a second voltage;
a control circuit configured to supply at least a first control signal;
an internal voltage generating circuit comprising:
a first capacitor having a first electrode and a second electrode;
a second capacitor having a third electrode and a fourth electrode;
a first switch configured to connect the second electrode to the first power supply line;
a second switch configured to connect the second electrode to the third electrode;
a third switch configured to connect the third electrode to the second power supply line; and
a fourth switch configured to connect the fourth electrode to the first power supply line;
wherein the first electrode is connected to the first control signal; and
wherein the control circuit is configured to:
when the internal voltage generating circuit performs a charge operation, set the first control signal to a first logic level, control the first switch to a conductive state to connect the second electrode to the first power supply line, control the second switch to a non-conductive state so that the second electrode is disconnected from the third electrode, control the third switch to a conductive state to connect the third electrode to the second power supply line, and control the fourth switch to a conductive state to connect the fourth electrode to the first power supply line; and
when the internal voltage generating circuit performs a discharge operation, set the first control signal to a second logic level, control the first switch to a non-conductive state to disconnect the second electrode from the first power supply line, control the second switch to a conductive state so that the second electrode is connected to the third electrode, control the third switch to a non-conductive state to disconnect the third electrode from the second power supply line, and control the fourth switch to a non-conductive state to disconnect the fourth electrode from the first power supply line.
2. The semiconductor device as claimed in claim 1 , wherein the second logic level is greater than the first logic level.
3. The semiconductor device as claimed in claim 1 , wherein the first voltage is greater than the second voltage.
4. The semiconductor device as claimed in claim 3 , wherein the second voltage is a ground.
5. The semiconductor device as claimed in claim 1 , wherein, during the charge operation, each of the first and second capacitors are charged to substantially to the first voltage.
6. The semiconductor device as claimed in claim 5 , wherein, during the discharge operation, a first internal node between the fourth electrode and the fourth switch has a third voltage approximately greater than the first voltage by a first magnitude.
7. The semiconductor device as claimed in claim 6 , wherein, during the discharge operation, a second internal node between the second and third electrodes has a fourth voltage greater than the first voltage by a second magnitude.
8. The semiconductor device as claimed in claim 7 , wherein the first magnitude is greater than the second magnitude.
9. The semiconductor device as claimed in claim 8 , wherein the first magnitude is approximately three and the second magnitude is approximately two.
10. The semiconductor device as claimed in claim 1 , wherein the internal voltage generating circuit alternates between the charge operation and the discharge operation.
11. The semiconductor device as claimed in claim 1 , wherein the control circuit is further configured to, when the internal voltage generating circuit is in a standby state, control the first switch to a conductive state to connect the second electrode to the first power supply line, control the second switch to a conductive state so that the second electrode is connected to the third electrode, control the third switch to a non-conductive state to disconnect the third electrode from the second power supply line, and control the fourth switch to a conductive state to connect the fourth electrode to the first power supply line.
12. The semiconductor device as claimed in claim 11 , wherein the control circuit is further configured to, when the internal voltage generating circuit is in a standby state, set the first control signal to the first logic level.
13. The semiconductor device as claimed in claim 11 , wherein the control circuit is further configured to, when the internal voltage generating circuit is in a standby state, set the first control signal to the second logic level.