INTERNAL VOLTAGE SUPPLYING DEVICE

• US 20100320988A1
• Filed: 09/02/2010
• Published: 12/23/2010
• Est. Priority Date: 09/29/2005
• Status: Active Grant

• Current Assignee: Chang-Ho Do
• Original Assignee: Chang-Ho Do
• Inventors: Do, Chang-Ho
• Granted Patent: US 8,183,912 B2
• Time in Patent Office: Days
• US Class Current: 323/284
• CPC Class Codes: G11C 5/143 Detection of memory cassette insertion or removal; Continuity checks of supply or ground lines; Detection of supply variations, interruptions or levels G11C5/148 takes precedence; Switching between alternative supplies G11C5/141 takes precedence
• CPC Class Codes: G11C 5/145 Applications of charge pumps; Boosted voltage circuits; Clamp circuits therefor G11C5/141 takes precedence

Abstract

An internal voltage supplying device. A reference voltage generator generates a first feedback voltage having a predetermined voltage ratio with respect to a core voltage. An adjusting mechanism adjusts the voltage ratio, and a voltage generator supplies a high voltage having a level higher than a level of the core voltage by the level of a threshold voltage or higher and maintains the level of the high voltage in accordance with the first feedback voltage.

Claims

1. An internal voltage supplying device, comprising:

a reference voltage generating means for generating a first feedback voltage having a predetermined voltage ratio with respect to a core voltage;

an adjusting means for adjusting the voltage ratio; and

a voltage generating means for supplying a high voltage having a level higher than a level of the core voltage by the level of a threshold voltage or higher and for maintaining said level of the high voltage in accordance with the first feedback voltage.

2. The internal voltage supplying device of claim 1, wherein the reference voltage generating means comprises:

a dividing unit to divide the core voltage into various levels and to output a plurality of dividing voltages; and

a selection unit to select one of the dividing voltages, as controlled by the adjusting means, and to output the selected dividing voltage as the first feedback voltage.

3. The internal voltage supplying device of claim 2, wherein the dividing unit comprises a plurality of resistors coupled in series and is to output voltages caught on each connect node of the resistors as the dividing voltages.

4. The internal voltage supplying device of claim 3, further comprising a plurality of capacitors coupled to connect nodes of the resistors, respectively.

5. The internal voltage supplying device of claim 3, wherein the adjusting means comprises a decoder to decode a test mode signal and output the decoded test mode signal as a selection signal.

6. The internal voltage supplying device of claim 3, wherein the adjusting means comprises:

a plurality of fuse option units, each fuse option unit comprising a fuse; and

a decoder to decode a signal corresponding to blowing states of the fuses of the fuse option units and to output the decoded signal as a selection signal.

7. The internal voltage supplying device of claim 3, wherein the adjusting means comprises:

a setup unit to sense setups of a plurality of fuse option units and test mode signals, and to output a plurality of setup signals; and

a decoder to decode the setup signals to output a selection signal.

8. The internal voltage supplying device of claim 7, wherein the setup unit comprises:

NOR gates each having an output signal of a respective fuse option unit and a respective test mode signal as inputs; and

inverters to invert output signals of the NOR gates to output the setup signals.

9. The internal voltage supplying device of claim 8, wherein the voltage generating means comprises:

a level sensing unit to sense a level of the high voltage with respect to the first feedback voltage to output a level signal;

an oscillation signal generating unit to generate an oscillation signal in response to the level signal; and

a pumping unit pumping to charge during an activation interval of the oscillation signal to output a high voltage.

10. The internal voltage supplying device of claim 9, wherein the level sensing unit comprises:

a feedback unit to divide the high voltage to output a second feedback voltage;

a comparator to compare a level of the second feedback voltage with respect to the first feedback voltage; and

a buffer to buffer an output signal of the comparator to output the level signal.

11. The internal voltage supplying device of claim 10, wherein the comparator comprises a differential amplifier having the second feedback voltage and the first feedback voltage as differential inputs.

12. The internal voltage supplying device of claim 11, wherein the feedback unit comprises first and second resistors coupled in series and is to output a voltage caught on a connect node of the first and second resistors as the second feedback voltage.

13. The internal voltage supplying device of claim 12, wherein the resistors comprise a passive device.

14. The internal voltage supplying device of claim 12, wherein the resistors comprise a transistor.

15. A method for operating an internal voltage supplying device, comprising:

generating a first feedback voltage having a predetermined voltage ratio with respect to a core voltage;

generating a second feedback voltage having a predetermined voltage ratio with respect to a high voltage; and

generating the high voltage having a level raised higher than a level of the core voltage by the level of a threshold voltage or higher, while maintaining a level of the second feedback voltage to correspond to the first feedback voltage, wherein the core voltage is used for storing data of a logic level in a cell, and the high voltage is used for activating the cell to allow the data to be transferred.

16. The method of claim 15, wherein the maintaining of the level of the second feedback voltage to correspond to the first feedback voltage comprises:

comparing the level of the second feedback voltage with the first feedback voltage; and

performing a charge pumping to raise the level of the second feedback voltage when the second feedback voltage is lower than the first feedback voltage.

17. The method of claim 16, wherein the predetermined voltage ratios are controlled by test mode signals or fuse option units.