Methods and apparatus to predictably change the output voltage of regulators

• US 6,208,127 B1
• Filed: 11/02/1999
• Issued: 03/27/2001
• Est. Priority Date: 11/02/1999
• Status: Expired due to Term

• Current Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Original Assignee: Maxim Integrated Products, Inc. (Analog Devices, Inc.)
• Inventors: Doluca, Tunç
• Primary Examiner(s): Riley, Shawn
• Application Number:
  US09/431,326
• Time in Patent Office: 511 Days
• Field of Search: 323/283, 323/351, 323/349, 323/222, 364/528.22
• US Class Current: 323/349
• CPC Class Codes: G05F 1/575 characterised by the feedback circuit

Abstract

Programmable voltage regulators that change from a first set-point voltage to a second set-point voltage at a controlled rate. The set-point signal is a multi-bit set-point signal with the rate of change in the regulator output between set-points being predetermined or externally controllable. Various embodiments are disclosed.

Claims

1. A programmable regulator comprising:

a counter having a first counter input coupled to a clock signal, and a counter output that counts toward a digital set-point;

a converter having a digital input coupled to the counter output, and an analog output that produces a signal responsive to the digital input; and

,

a regulating device receiving the analog output and providing a regulator output voltage responsive to the analog output, the regulator output voltage determined by the digital set-point with a rate of change determined by a frequency of the clock signal.

2. The programmable regulator of claim 1 wherein the counter output counts from a minimum value to a maximum value when the counter is enabled.

3. The programmable regulator of claim 1, the converter further having an analog input coupled to an analog set-point signal, and the analog output further responsive to the analog input.

4. The programmable regulator of claim 1 further comprising a digital comparator having a first comparator input, a second comparator input, and a comparator output, said first comparator input receiving a digital set-point signal, said second comparator input coupled to the counter output, and said comparator output coupled to the first counter input to enable counting in one of an up direction and a down direction responsive to a difference between the digital set-point signal and the counter output.

5. The programmable regulator of claim 1 wherein the converter is an digital to analog converter.

6. The programmable regulator of claim 1 wherein the digital to analog converter is a multiplying digital to analog converter.

7. The programmable regulator of claim 1 further comprised of an oscillator having an oscillator output coupled to the second counter input to provide the clock signal thereto.

8. The programmable regulator of claim 1 wherein the regulator device is a switching regulator device.

9. The programmable regulator of claim 1 wherein the regulating device is a step-down regulator device.

10. The programmable regulator of claim 1 wherein the regulating device is a step-up regulator device.

11. The programmable regulator of claim 1 wherein the regulating device is a linear regulator device.

12. The programmable regulator of claim 1 wherein the regulating device is an inverting regulator device.

13. A programmable regulator comprising:

a digital to analog converter receiving a digital set-point signal and providing an analog output;

an integrator integrating the analog output to produce an integrator output; and

,

a regulating device receiving the integrator output and providing a regulator output voltage responsive to the integrator output.

14. The programmable regulator of claim 13 wherein the regulating device is a switching regulator device.

15. The programmable regulator of claim 13 wherein the regulating device is a step-down regulator device.

16. The programmable regulator of claim 13 wherein the regulating device is a step-up regulator device.

17. The programmable regulator of claim 13 wherein the regulating device is a linear regulator device.

18. The programmable regulator of claim 13 wherein the regulating device is an inverting regulator device.

19. A method of controlling an output of a regulator comprising;

counting a clock signal to produce a digital count that counts toward a digital set-point;

converting the digital count to an analog signal; and

,

controlling a regulating device with the analog signal to adjust the output of the regulator to a steady state value determined by the digital set-point with a rate of change for the output determined by a frequency of the clock signal.

20. The method of claim 19 further comprising receiving an analog set-point signal, wherein the output is further controlled with the analog set-point signal, and wherein the counting is from a minimum value to a maximum value when counting is enabled.

21. The method of claim 19 further comprising;

receiving the digital set-point; and

comparing the digital set-point to the digital count and increasing or decreasing the digital count to reach the digital set-point.

22. The method of claim 19 wherein converting the digital count to the analog signal comprises converting the digital count to the analog signal with a digital to analog converter.

23. The method of claim 19 wherein converting the digital count to the analog signal comprises converting the digital count to the analog signal with a multiplying digital to analog converter.

24. The method of claim 21 wherein a difference between the digital set-point and the digital count is accumulated at the desired rate using a clocked counter.

25. The method of claim 21 wherein a difference between the digital set-point and the digital count is accumulated using a clocked up/down counter.

26. The method of claim 19 wherein controlling the regulating device with the analog signal comprises controlling a switching regulating device.

27. The method of claim 19 wherein controlling the regulating device with the analog signal comprises controlling a step-down regulating device.

28. The method of claim 19 wherein controlling the regulating device with the analog signal comprises controlling a step-up regulating device.

29. The method of claim 19 wherein controlling the regulating device with the analog signal comprises controlling a linear regulating device.

30. The method of claim 19 wherein controlling the regulating device with the analog signal comprises controlling an inverting regulating device.

31. A method of controlling a programmable regulator comprising:

providing a digital set-point signal;

converting the digital set-point signal to an analog signal;

limiting a rate of change of the analog signal; and

controlling a regulating device responsive to the analog signal.

32. The method of claim 31 wherein controlling the regulating device comprises controlling a switching regulating device.

33. The method of claim 31 wherein controlling the regulating device comprises controlling a step-down regulating device.

34. The method of claim 31 wherein controlling the regulating device comprises controlling a step-up regulating device.

35. The method of claim 31 wherein controlling the regulating device comprises controlling a linear regulating device.

36. The method of claim 31 wherein controlling the regulating device comprises controlling an inverting regulating device.

37. A method of controlling an output of a regulator comprising;

providing a digital set-point value;

comparing the digital set-point value to a digital count;

incrementing the digital count if the digital count is less than the digital set-point value;

decrementing the digital count if the digital count is more than the digital set-point value;

controlling a regulating device with the digital count to adjust the output of the regulator to a steady state value determined by the digital set-point value with a rate of change for the output determined by a rate of change for the digital count.

38. The method of claim 37 wherein controlling the regulating device further comprises converting the digital count to an analog signal with a digital to analog converter and controlling the output of the regulating device with the analog signal.

39. The method of claim 38 wherein converting the digital count to an analog signal comprises converting the digital count to an analog signal with a multiplying digital to analog converter.

40. The method of claim 37 wherein the difference between the digital set-point value and digital count is accumulated using a clocked counter.

41. The method of claim 37 wherein a difference between the digital set-point value and digital count is accumulated using a clocked up/down counter.

42. The method of claim 38 wherein controlling the regulating device with the analog signal comprises controlling a switching regulating device.

43. The method of claim 38 wherein controlling the regulating device with the analog signal comprises controlling a step-down regulating device.

44. The method of claim 38 wherein controlling the regulating device with the analog signal comprises controlling a step-up regulating device.

45. The method of claim 38 wherein controlling the regulating device with the analog signal comprises controlling a linear regulating device.

46. The method of claim 38 wherein controlling the regulating device with the analog signal comprises controlling an inverting regulating device.

47. A method of controlling a programmable regulator comprising:

providing a digital set-point signal;

converting the digital set-point signal to an analog signal;

integrating the analog signal to produce a control signal; and

,

controlling a regulating device responsive to the control signal.

48. The method of claim 47 wherein controlling the regulating device comprises controlling a switching regulating device.

49. The method of claim 47 wherein controlling the regulating device comprises controlling a step-down regulating device.

50. The method of claim 47 wherein controlling the regulating device comprises controlling a step-up regulating device.

51. The method of claim 47 wherein controlling the regulating device comprises controlling a linear regulating device.

52. The method of claim 47 wherein controlling the regulating device comprises controlling an inverting regulating device.