DC/DC CONVERTER WITH IMPROVED STABILITY

• US 20090027015A1
• Filed: 09/29/2008
• Published: 01/29/2009
• Est. Priority Date: 08/19/2005
• Status: Active Grant

• Current Assignee: Laszlo Lipcsei, Sorin Hornet
• Original Assignee: Laszlo Lipcsei, Sorin Hornet
• Inventors: HORNET, Sorin, LIPCSEI, Laszlo
• Granted Patent: US 7,719,247 B2
• Time in Patent Office: Days
• US Class Current: 323/233
• CPC Class Codes: H02M 1/143 using compensating arrangements for reducing noise from the supply in transmission systems H04B15/005
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

The DC/DC converter according to one embodiment includes a switch, an inductor, a capacitor, a resistor, and a voltage divider. The switch is coupled to the input voltage. The inductor is used for coupling the first switch to an output node of the DC/DC converter so as to generate the output voltage at the output node. The capacitor is coupled to the output voltage. The resistor is coupled to the capacitor in series, and is coupled to ground. The voltage divider is coupled across the capacitor so as to reduce the zero frequency of the DC/DC converter.

Claims

1-19. -19. (canceled)

20. A DC-DC converter for converting an input DC voltage to an output DC voltage, comprising:

a first switch coupled to said input voltage;

an inductor coupled to said first switch in series for generating said output DC voltage at an output node;

a capacitor coupled to said output node;

a first resistor for coupling said capacitor to ground;

a voltage divider coupled to said capacitor in parallel for generating a feedback voltage; and

a controller receiving said feedback voltage and controlling said first switch in response to said feedback voltage for controlling said output DC voltage at a predetermined voltage.

21. The DC-DC converter as claimed in claim 20, wherein said voltage divider comprises:

a second resistor; and

a third resistor coupled to said second resistor in series for generating said feedback voltage between said second resistor and said third resistor.

22. The DC-DC converter as claimed in claim 20, wherein said controller generates a first PWM signal to control said first switch.

23. The DC-DC converter as claimed in claim 20, wherein said capacitor comprises a ceramic capacitor.

24. The DC-DC converter as claimed in claim 20, further comprising:

a second switch for coupling said first switch to ground.

25. The DC-DC converter as claimed in claim 24, wherein said controller coupled to said second switch for controlling said first switch and said second switch according to said feedback voltage.

26. The DC-DC converter as claimed in claim 25, wherein said controller generates a second PWM signal to control said second switch.

27. The DC-DC converter as claimed in claim 25, wherein said second switch comprises a diode.

28. The DC-DC converter as claimed in claim 25, wherein said second switch comprises a metal-oxide semiconductor (MOS) transistor.

29. The DC-DC converter as claimed in claim 20, wherein said first switch comprises a metal-oxide semiconductor (MOS) transistor.

30. A method for converting an input DC voltage to an output DC voltage, comprising:

receiving said input DC voltage;

controlling a first switch to discontinuously couple said input DC voltage to an inductor for generating said output DC voltage;

coupling an capacitor to said inductor;

coupling said capacitor to ground through a first resistor; and

generating a feedback voltage signal in respond to said output DC voltage at a voltage divider coupled in parallel to said capacitor.

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

controlling said first switch according to said feedback voltage ripple.

32. The method as claimed in claim 30, wherein said controlling said first switch further comprises:

controlling said first switch with a PWM signal.

33. The method as claimed in claim 30, wherein said voltage divider comprises a second resistor and a third resistor coupled in series.

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

providing a discharging path by a second switch coupled to said first switch and ground.

35. The method as claimed in claim 34, further comprising:

controlling said second switch according to said feedback voltage ripple.

36. The method as claimed in claim 34, further comprising:

controlling said second switch with a PWM signal.

37. The method as claimed in claim 34, wherein said second switch comprises a diode.

38. The method as claimed in claim 34, wherein said second switch comprises a metal-oxide semiconductor (MOS) transistor.

39. The method as claimed in claim 30, wherein said capacitor comprises a ceramic capacitor.

40. The method as claimed in claim 30, wherein said first switch comprises a metal-oxide semiconductor (MOS) transistor.