DC-to-DC converter with improved transient response

• US 7,031,174 B2
• Filed: 08/26/2003
• Issued: 04/18/2006
• Est. Priority Date: 10/26/2000
• Status: Expired due to Term

• Current Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Original Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Inventors: Lipcsei, Laszlo
• Primary Examiner(s): Patel, Rajnikant B.
• Application Number:
  US10/648,085
• Publication Number:
  US 20050030775A1
• Time in Patent Office: 966 Days
• Field of Search: 323/282, 323/283, 323/284, 323/285, 323/288, 323/280, 363/17, 363/97, 363/98, 363/72, 363/16, 363/132
• US Class Current: 363/98
• CPC Class Codes: H02M 1/15 using active elements
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel
• CPC Class Codes: H02M 3/1586 switched with a phase shift, i.e. interleaved

Abstract

A DC-to-DC converter includes a comparator, a driver, and a pair of switches. The comparator compares the output voltage with a reference voltage signal and generates a PWM signal. The driver drives the switches so as to force the output voltage to follow the reference signal. In a multiphase architecture, two or more such converter circuits are incorporated to minimize the output voltage ripple and further reduce the recovery time. In a two-phase architecture, two reference signals are phase-shifted by 180 degrees. In an N-phase architecture, the reference signals are phase-shifted by 360/N degrees.

Claims

1. A DC-DC converter comprising:

a comparator configured to compare a first signal representative of an output voltage of said DC-DC converter with a periodic reference signal having a DC offset determined by a DC reference voltage source and to provide an output signal that drives said output voltage of said DC-DC converter towards a pre-established value.

2. The DC-DC converter of claim 1, wherein said output signal comprises a pulse width modulated signal.

3. The DC-DC converter of claim 2, wherein a pulse width of said pulse width modulated signal changes when said output voltage is different than said pre-established value.

4. The DC-DC converter of claim 1, wherein said DC-DC further comprises a driver and a pair of switches, and wherein said driver drives said pair of switches, one high, one low which alternatively control said output voltage in response to said output signal from said comparator.

5. The DC-DC converter of claim 4, further comprising a low pass filter electrically coupled to an output of said pair of switches.

6. The DC-DC converter of claim 5, wherein each of said switches comprises a metal oxide semiconductor field effect transistor.

7. A DC to DC converter comprising:

a means for comparing a first signal representative of an output voltage of said DC-DC converter with a periodic reference signal having a DC offset determined by a DC reference voltage source and providing an output signal that drives said output voltage of said DC-DC converter towards a pre-established value.

8. The DC-DC converter of claim 7, wherein said output signal comprises a pulse width modulated signal.

9. The DC-DC converter of claim 8, wherein a pulse width of said pulse width modulated signal changes when said output voltage is different than said pre-established value.

10. A method of controlling an output voltage of a DC to DC converter, said method comprising:

comparing a first signal representative of an output voltage of said DC-DC converter with a periodic reference signal having a DC offset determined by a DC reference voltage source;

providing an output signal in response to said comparing operation; and

driving an output voltage of said DC-DC converter towards a pre-established value in response to said output signal.

11. The method of claim 10, wherein said output signal comprises a pulse width modulated signal.

12. An electronic device comprising:

a DC-DC converter, said DC-DC converter comprising;

a comparator configured to compare first signal representative of an output voltage with a periodic reference signal having a DC offset determined by a DC reference voltage source and to provide an output signal that drives an output voltage of said DC-DC converter towards a pre-established value.

13. The electronic device of claim 12, wherein said output voltage of said DC-DC converter is provided to a system load of said electronic device.

14. The electronic device of claim 13, wherein said system load comprises a microprocessor.

15. The electronic device of claim 12, wherein said output signal comprises a pulse width modulated signal.

16. The electronic device of claim 15, wherein a pulse width of said pulse width modulated signal changes when said output voltage is different than said pre-established value.

17. The electronic device of claim 12, wherein said DC-DC further comprises a driver and a pair of switches, and wherein said driver drives said pair of switches, one high, one low which alternatively control said output voltage in response to said output signal from said comparator.

18. The electronic device of claim 17, further comprising a low pass filter electrically coupled to an output of said pair of switches.

19. The DC-DC converter of claim 18, wherein each of said switches comprises a metal oxide semiconductor field effect transistor.