SEMICONDUCTOR DEVICE

• US 20110204963A1
• Filed: 02/18/2011
• Published: 08/25/2011
• Est. Priority Date: 02/25/2010
• Status: Active Grant

• Current Assignee: Magnachip Semiconductor Limited (Magnachip Semiconductor)
• Original Assignee: Magnachip Semiconductor Limited (Magnachip Semiconductor)
• Inventors: KIM, Jung-hyun
• Granted Patent: US 8,729,956 B2
• Time in Patent Office: Days
• US Class Current: 327/536
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps

Abstract

A semiconductor device is provided, including a charge-pumping unit configured to charge-pump power voltage in every period of a pumping clock to generate pumping voltage, a first voltage level detection unit configured to detect a maximum voltage level of the generated pumping voltage, a second voltage level detection unit configured to detect a minimum voltage level of the generated pumping voltage, and a pumping clock generating unit configured to generate the pumping clock, the pumping clock having a frequency that is adjusted in response to an output signal of the first and the second voltage level detection units.

Claims

1. A semiconductor device, comprising:

a charge-pumping unit configured to charge-pump power voltage in every period of a pumping clock to generate pumping voltage;

a first voltage level detection unit configured to detect a maximum voltage level of the generated pumping voltage;

a second voltage level detection unit configured to detect a minimum voltage level of the generated pumping voltage; and

a pumping clock generating unit configured to generate the pumping clock, the pumping clock having a frequency that is adjusted in response to an output signal of the first and the second voltage level detection units.

2. The semiconductor device as claimed in claim 1, further comprising:

a driving control unit configured to control charge-pumping driving power of the charge-pumping unit in response to the output signal of the first voltage level detection unit.

3. The semiconductor device as claimed in claim 2, wherein the first voltage level detection unit comprises:

a first detection control pulse generating unit configured to toggle a first detection control pulse sequentially, the first detection control pulse having a predetermined number that is set in an expected first detection section at every predetermined number of period of the pumping clock;

a maximum reference voltage generating unit configured to generate a maximum reference voltage, the maximum reference voltage having a level that is adjusted according to a predetermined unit in response to a maximum reference level control code; and

a maximum voltage level comparing unit configured to;

compare a voltage level of the generated pumping voltage with the level of the maximum reference voltage sequentially in response to the toggling of the predetermined number of the first detection control pulse, respectively; and

determine each bit value of the maximum reference level control code sequentially in response to a result of the comparing of the voltage level of the generated pumping voltage with the level of the maximum reference voltage.

4. The semiconductor device as claimed in claim 3, wherein the second voltage level detection unit comprises:

a second detection control pulse generating unit configured to toggle a second detection control pulse sequentially, the second detection control pulse having a predetermined number that is set in an expected second detection section at every predetermined number of period of the pumping clock;

a minimum reference voltage generating unit configured to generate a minimum reference voltage, the minimum reference voltage having a level that is adjusted according to a predetermined unit in response to a minimum reference level control code; and

a minimum voltage level comparing unit configured to;

compare the voltage level of the generated pumping voltage with the level of the minimum reference voltage sequentially in response to the toggling of the predetermined number of the second detection control pulse, respectively; and

determine each bit value of the minimum reference level control code sequentially in response to a result of the comparing of the voltage level of the generated pumping voltage with the level of the minimum reference voltage.

5. The semiconductor device as claimed in claim 4, wherein the charge-pumping unit comprises:

a pumping control unit configured to respectively generate;

a plurality of first control signals and a plurality of fourth control signals in which a number of activated signals is determined in response to a driving control code in a pre-charge period of the pumping clock; and

a plurality of second control signals and a plurality of third control signals in which a number of activated signals is determined in response to a driving control code in a pumping period of the pumping clock; and

a charge pump configured to perform a charge-pumping operation in response to the plurality of first to fourth control signals.

6. The semiconductor device as claimed in claim 5, wherein the charge pump comprises:

a plurality of first switches having one end connected to power voltage in parallel and on/off controlled in response to the plurality of first control signals, respectively;

a first capacitor having one end commonly connected to an other end of the plurality of first switches;

a plurality of second switches having one end connected to the power voltage in parallel, an other end connected to an other end of the first capacitor in parallel, and on/off controlled in response to the plurality of second control signals;

a plurality of third switches having one end connected to the one end of the first capacitor in parallel, an other end connected to pumping voltage in parallel, and on/off controlled in response to the plurality of third control signals;

a second capacitor having one end connected to the pumping voltage and an other end connected to ground voltage; and

a plurality of fourth switches having one end connected to the other end of the first capacitor in parallel, an other end connected to ground voltage in parallel, and on/off controlled in response to the plurality of fourth control signals.

7. The semiconductor device as claimed in claim 5, wherein the driving control unit is further configured to perform a set operation of a value of the maximum reference level control code to determine a value of the driving control code.

8. The semiconductor device as claimed in claim 5, wherein the driving control unit is further configured to select one of a plurality of driving control codes, the selected driving control code being configured to correspond to the maximum reference level control code, the plurality of driving control codes having values that are preset in accordance with a variable value of the maximum reference level control code.

9. The semiconductor device as claimed in claim 4, wherein the pumping clock generating unit comprises:

a code operation unit configured to perform an operation set between a value of the maximum reference level control code and a value of the minimum reference level control code to generate a frequency control code; and

a pumping clock output unit configured to receive a pumping reference clock having a predetermined reference frequency to output the pumping clock of which frequency is changed based on a ratio corresponding to the frequency control code.

10. The semiconductor device as claimed in claim 4, wherein the pumping clock generating unit comprises:

a frequency control code table configured to select one of plurality of frequency control codes, the selected frequency control code being configured to correspond to the maximum and minimum reference level control codes, the plurality of frequency control codes having values that are preset in accordance with a variable value of the maximum and minimum reference level control codes; and

a pumping clock output unit configured to receive a pumping reference clock having a predetermined reference frequency to output the pumping clock of which frequency is changed according to a ratio corresponding to the selected frequency control code.

11. A semiconductor device, comprising:

a charge-pumping unit configured to charge-pump power voltage to generate pumping voltage;

a voltage level detection unit configured to detect a maximum voltage level of the generated pumping voltage; and

a driving control unit configured to control charge-pumping driving power of the charge-pumping unit in response to an output signal of the voltage level detection unit.

12. The semiconductor device as claimed in claim 11, wherein the voltage level detection unit comprises:

a detection control pulse generating unit configured to toggle a detection control pulse sequentially, the detection control pulse having a predetermined number that is set in an expected detection section at every predetermined number of period of a pumping clock;

a maximum reference voltage generating unit configured to generate maximum reference voltage having a level is adjusted in response to a maximum reference level control code; and

a maximum voltage level comparing unit configured to;

compare a voltage level of the pumping voltage with the level of the maximum reference voltage sequentially in response to the toggling of the predetermined number of the detection control pulse, respectively; and

determine each bit value of the maximum reference level control code sequentially in response to a result of the comparing of the voltage level of the pumping voltage with the level of the maximum reference voltage.

13. The semiconductor device as claimed in claim 12, wherein the charge-pumping unit comprises:

a pumping control unit configured to respectively generate;

a plurality of first control signals and a plurality of fourth control signals in which a number of activated signals is determined in response to a driving control code in a pre-charge period of the pumping clock; and

a plurality of second control signals and a plurality of third control signals in which a number of activated signals is determined in response to the driving control code in a pumping period of the pumping clock; and

a charge pump configured to perform a charge-pumping operation in response to the plurality of first to fourth control signals.

14. The semiconductor device as claimed in claim 13, wherein the charge pump comprises:

a plurality of first switches having one end connected to power voltage in parallel and on/off controlled in response to the plurality of first control signals, respectively;

a first capacitor having one end commonly connected to an other end of the plurality of first switches;

a plurality of second switches having one end connected to the power voltage in parallel, an other end connected to an other end of the first capacitor in parallel, and on/off controlled in response to the plurality of second control signals;

a plurality of third switches having one end connected to the one end of the first capacitor in parallel, an other end connected to pumping voltage in parallel, and on/off controlled in response to the plurality of third control signals;

a second capacitor having one end connected to the pumping voltage and an other end connected to ground voltage; and

a plurality of fourth switches having one end connected to the other end of the first capacitor in parallel, an other end connected to ground voltage in parallel, and on/off controlled in response to the plurality of fourth control signals.

15. The semiconductor device as claimed in claim 13, wherein the driving control unit is further configured to perform a set operation of a value of the maximum reference level control code to determine a value of the driving control code.

16. The semiconductor device as claimed in claim 13, wherein the driving control unit is further configured to select one of a plurality of driving control codes, the selected driving control code being configured to correspond to the maximum reference level control code, the plurality of driving control codes having values that are preset in accordance with a variable value of the maximum reference level control code.

17. A method for operating a semiconductor device in which pumping voltage is generated by performing charge-pumping with pumping driving power corresponding to a driving control code in every period of a pumping clock where a first display period, a first blanking period, a second display period, and a second blanking period are repeated sequentially, the method comprising:

detecting;

a difference of a maximum voltage level and a minimum voltage level of the pumping voltage in the first display period; and

a maximum voltage level of the pumping voltage in the second display period;

adjusting a frequency of the pumping clock in the first blanking period in response to the difference between a maximum voltage level and a minimum voltage level of pumping voltage which is detected through the first detection; and

determining a value of the driving control code in the second blanking period in response to a result of the detecting of the maximum voltage level.

18. The method as claimed in claim 17, wherein the adjusting of the frequency comprises:

if the difference in the voltage level between the maximum voltage level and the minimum voltage level of the pumping voltage determined through the detecting of the difference is less than a predetermined reference level difference, applying the frequency of the pumping clock slowly according to a predetermined unit in the first blanking period;

if the difference in the voltage level between the maximum voltage level and the minimum voltage level of the pumping voltage determined through the detecting of the difference is greater than the predetermined reference level difference, applying the frequency of the pumping clock fast according to the predetermined unit in the first blanking period; and

if the difference in the voltage level between the maximum voltage level and the minimum voltage level of the pumping voltage determined through the detecting of the difference is consistent with the predetermined reference level difference within a predetermined scope, maintaining the frequency of the pumping clock.

19. The method as claimed in claim 17, wherein the detection of the difference comprises:

determining;

a value of a maximum reference level control code corresponding to the maximum voltage level of the pumping voltage in an operation section of the first display period; and

a value of a minimum reference level control code corresponding to the minimum voltage level of the pumping voltage in the operation section of the first display period; and

generating a frequency control code in response to the maximum reference level control code and the minimum reference level control code in the operation section of the first display period.

20. The method as claimed in claim 19, wherein the determining of the values of the maximum and minimum reference level control codes comprises:

determining;

an each bit value of the maximum reference level control code sequentially by comparing a voltage level of the pumping voltage in every expected section of the detecting of the difference of each period with a level of a maximum reference voltage, the level of the maximum reference voltage being adjusted according to a predetermined unit based on the value of the maximum reference level control code, a period of the pumping clock being repeated for a predetermined number of times in the operation section of the first display period; and

an each bit value of the minimum reference level control code sequentially by comparing a voltage level of pumping voltage in every expected section of the detecting of the maximum voltage level of each period with a level of a minimum reference voltage, the level of the minimum reference voltage being adjusted according to a predetermined unit based on the value of the minimum reference level control code, a period of the pumping clock being repeated for a predetermined number of times in the operation section of the first display period; and

maintaining the values of the maximum and minimum reference level control codes that are determined in the operation section of the first display period in an operation section of the first blanking period.

21. The method as claimed in claim 19, wherein the generating of the frequency control code comprises:

performing an operation set between the value of the maximum reference level control code and the value of the minimum reference level control code to generate the frequency control code; and

selecting the frequency control code corresponding to the maximum and minimum reference level control codes from among a plurality of frequency control codes of which values are preset in accordance with a variable value of the maximum and minimum reference level control codes.

22. The method as claimed in claim 19, wherein the adjusting of the frequency comprises:

receiving a pumping reference clock having a reference frequency set in an operation section of the first blanking period;

adjusting a frequency of the pumping clock based on a ratio corresponding to the frequency control code; and

maintaining the adjusted frequency of the pumping clock in the first blanking period regardless of a change in the frequency control code in the operation section of the first display period.

23. The method as claimed in claim 17, wherein the determining of the value of the driving control code comprises:

if the detected maximum voltage level of the pumping voltage is less than a predetermined reference level by greater than a predetermined scope, increasing the value of the driving control code;

if the detected maximum voltage level of the pumping voltage is greater than the predetermined reference level by greater than the predetermined scope, decreasing the value of the driving control code; and

if the detected maximum voltage level of the pumping voltage is consistent with the predetermined reference level within the predetermined scope, maintaining the value of the driving control code.

24. The method as claimed in claim 23, further comprising:

if the value of the driving control code increases in an operation section of the second blanking period, generating the pumping voltage by charge-pumping power voltage with increased charge-pumping driving power;

if the value of the driving control code decreases in the operation section of the second blanking period, generating the pumping voltage by charge-pumping power voltage with decreased charge-pumping driving power;

if the value of the driving control code is maintained in the operation section of the second blanking period, generating the pumping voltage by charge-pumping power voltage with previous charge-pumping driving power; and

if the value of the driving control code is changed in an operation section of the first and the second display periods, generating the pumping voltage by charge-pumping power voltage with previous charge-pumping driving power.

25. The method as claimed in claim 23, wherein, in a power on period that is performed before an operation section of the first and the second display periods and the first and the second blanking periods:

the value of the driving control code is always fixed to a maximum value regardless of the determining of the value; and

the pumping voltage is generated by charge-pumping power voltage with maximum charge-pumping driving power accordingly.

26. The method as claimed in claim 17, wherein the detecting of the maximum voltage level comprises:

determining an each bit value of a maximum reference level control code sequentially by comparing a voltage level of the pumping voltage in every expected section of the detections of the difference and the maximum voltage level of each period with a level of a maximum reference voltage, the level of the maximum reference voltage being adjusted according to a predetermined unit based on a value of a maximum reference level control code, a period of the pumping clock being repeated for a predetermined number of times in an operation section of the second display period; and

maintaining the value of the maximum reference level control code in an operation section of the second blanking period, the value of the maximum reference level control code being determined in the operation section of the second display period.

27. The method as claimed in claim 26, wherein the determining of the value of the driving control code comprises:

generating the driving control code by performing a set operation of the value of the maximum reference level control code; and

selecting the driving control code corresponding to the maximum reference level control code from among a plurality of driving control codes having values that are preset in accordance with a variable value of the maximum reference level control code.

28. A method for operating a semiconductor device in which pumping voltage is generated by charge-pumping power voltage with pumping driving power corresponding to a driving control code in repeated display periods and blanking periods, the method comprising:

detecting a maximum voltage level of the pumping voltage in the display periods; and

determining a value of the driving control code in the blanking periods in response to the detected maximum voltage level.

29. The method as claimed in claim 28, wherein the determining of the value comprises:

if the detected maximum voltage level of the pumping voltage is less than a predetermined reference level by greater than a predetermined scope, increasing the value of the driving control code;

if the detected maximum voltage level of the pumping voltage is greater than the predetermined reference level by greater than the predetermined scope, decreasing the value of the driving control code; and

if the detected maximum voltage level of the pumping voltage is consistent with the predetermined reference level within the predetermined scope, maintaining the value of the driving control code.

30. The method as claimed in claim 29, further comprising:

if the value of the driving control code increases in an operation section of the blanking periods, generating the pumping voltage by charge-pumping power voltage with increased charge-pumping driving power;

if the value of the driving control code decreases in the operation section of the blanking periods, generating the pumping voltage by charge-pumping power voltage with decreased charge-pumping driving power;

if the value of the driving control code is maintained in the operation section of the blanking period, generating the pumping voltage by charge-pumping power voltage with previous charge-pumping driving power; and

if the value of the driving control code is changed in an operation section of the display periods, generating the pumping voltage by charge-pumping power voltage with previous charge-pumping driving power.

31. The method as claimed in claim 29, wherein, in a power on period that is entered as power is supplied and is performed before the display and blanking periods:

the value of the driving control code is always fixed to a maximum value regardless of the determining of the value; and

the pumping voltage is generated by charge-pumping power voltage with maximum charge-pumping driving power accordingly.

32. The method as claimed in claim 28, wherein the detecting of the maximum voltage level comprises:

determining an each bit value of a maximum reference level control code sequentially by comparing a voltage level of the pumping voltage in every expected section of the detecting of the maximum voltage level of each period with a level of a maximum reference voltage, the level of the maximum reference voltage being is adjusted according to a predetermined unit based on the value of a maximum reference level control code, a period of the pumping clock being repeated for a predetermined number of times in an operation section of the display periods; and

maintaining the value of the maximum reference level control code in an operation section of the blanking periods.

33. The method as claimed in claim 32, wherein the determining of the value comprises:

generating the driving control code by performing a set operation of the value of the maximum reference level control code; and

selecting the driving control code corresponding to the maximum reference level control code from among a plurality of driving control codes having values that are preset in accordance with a variable value of the maximum reference level control code.

34. A method for operating a semiconductor device in which pumping voltage is generated by charge-pumping power voltage with pumping driving power corresponding to a driving control code in repeated display periods and blanking periods, the method comprising:

detecting a maximum voltage level and a minimum voltage level of the pumping voltage in the display periods;

adjusting a frequency of the pumping clock in the blanking periods in response to a difference between the detected maximum voltage level and the detected minimum voltage level of the pumping voltage; and

determining a value of the driving control code in the blanking periods in response to the detected maximum voltage level of the pumping voltage.

35. The method as claimed in claim 34, wherein the adjusting of the frequency comprises:

if a difference in a voltage level between the detected maximum voltage level and the detected minimum voltage level of the pumping voltage is less than a predetermined reference level difference, applying the frequency of the pumping clock slowly as much as a predetermined unit in the blanking periods;

if a difference in a voltage level between the detected maximum voltage level and the detected minimum voltage level of the pumping voltage is greater than the predetermined reference level difference, applying the frequency of the pumping clock fast as much as the predetermined unit in the blanking periods; and

if a difference in a voltage level between the detected maximum voltage level and the detected minimum voltage level of the pumping voltage is consistent with the predetermined reference level difference within in a predetermined scope, maintaining the frequency of the pumping clock in the blanking periods.

36. The method as claimed in claim 34, wherein the determining of the value comprises:

if the detected maximum voltage level of the pumping voltage is less than a predetermined reference level by greater than a predetermined scope, increasing the value of the driving control code;

if the detected maximum voltage level of the pumping voltage is greater than the predetermined reference level by greater than the predetermined scope, decreasing the value of the driving control code; and

if the detected maximum voltage level of the pumping voltage is consistent with the predetermined reference level within the predetermined scope, maintaining the value of the driving control code.

37. The method as claimed in claim 34, wherein the detecting comprises determining, in an operation section of the display periods:

a value of a maximum reference level control code corresponding to the maximum voltage level of the pumping voltage; and

a value of a minimum reference level control code corresponding to the minimum voltage level of the pumping voltage.

38. The method as claimed in claim 37, wherein the adjusting of the frequency comprises:

generating a frequency control code by performing an operation set between the value of the maximum reference level control code and the value of the minimum reference level control code;

selecting the frequency control code corresponding to the maximum and minimum reference level control codes from among a plurality of frequency control codes having values that are preset in accordance with a variable value of the maximum and minimum reference level control codes;

receiving a pumping reference clock having a reference frequency set in an operation section of the blanking periods;

adjusting a frequency of the pumping clock based on a ratio corresponding to the frequency control code; and

maintaining the adjusted frequency of the pumping clock in the blanking periods regardless of a change in the frequency control code in an operation section of the display periods.

39. The method as claimed in claim 37, wherein the determining of the value of the driving control code comprises:

generating the driving control code by performing a set operation of the determined value of the maximum reference level control code; and

selecting the driving control code corresponding to the maximum reference level control code from among a plurality of driving control codes that are preset in accordance with a variable value of the maximum reference level control code.