Spike control apparatus for DC-DC converter

• US 6,909,619 B2
• Filed: 01/29/2001
• Issued: 06/21/2005
• Est. Priority Date: 07/03/2000
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Matsuda, Kouichi, Saeki, Mitsuo, Nakazawa, Shigeaki
• Primary Examiner(s): STERRETT, JEFFREY L
• Application Number:
  US09/770,238
• Publication Number:
  US 20020001206A1
• Time in Patent Office: 1,604 Days
• Field of Search: 363/50, 363/55, 363/56, 363/56.04, 363/56.07, 363/124
• US Class Current: 363/50
• CPC Class Codes: H02M 1/38 Means for preventing simultaneous conduction of switches
• 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

There are disclosed a synchronous rectifying type of DC—DC converter, a DC—DC converter control circuit constituting such a type of DC—DC converter, a monitor circuit for monitoring an operation of a DC—DC converter, and an electronic equipment having a DC—DC converter, considering a conduction current. A DC—DC converter has a main switch and a synchronous rectifying switch, in which said main switch and said synchronous rectifying switch are alternately turned on so that a voltage of a DC electric power is transformed and outputted. A state that said main switch and said synchronous rectifying switch are simultaneously turned on is detected.

Claims

1. A switching regulator, comprising:

a main switch;

a synchronous switch, where the main switch and the synchronous switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a detection circuit that detects when the main switch and the synchronous switch are simultaneously turned on,

wherein the detection circuit monitors a driving signal that drives at least one of the main switch and the synchronous switch, and detects a voltage across one of the main switch and the synchronous switch to detect a state in which the main switch and the synchronous switch are simultaneously turned on.

2. A switching regulator according to claim 1, wherein the switching regulator further comprises a display unit that displays when the main switch and the synchronous switch are simultaneously turned on.

3. A switching regulator according to claim 1, wherein the switching regulator further comprises an operation stop circuit that stops a conversion operation of the switching regulator in a case where the main switch and the synchronous switch are simultaneously turned on.

4. A switching regulator according to claim 1, wherein the detection circuit monitors at least one of the main switch and the synchronous switch.

5. A switching regulator according to claim 1, wherein the detection circuit monitors a direction of a current conducting through the synchronous switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

6. A switching regulator according to claim 1, wherein the detection circuit monitors a magnitude of a current conducting through the main switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

7. A switching regulator, comprising:

a first switch;

an inductor which is connected in series with the first switch;

a second switch disposed between a connecting point of the first switch with the inductor and a ground point, in which the first switch and the second switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a detection circuit that detects a state that the first switch and the second switch are simultaneously turned on,

wherein the detection circuit monitors a driving signal that drives at least one of the first switch and the second switch, and detects a voltage across one of the first switch and the second switch to detect the state in which the first switch and the second switch are simultaneously turned on.

8. A switching regulator, comprising:

a main switch;

a synchronous switch where the main switch and the synchronous switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a switching control circuit that controls the main switch and the synchronous switch, comprising a detection circuit that detects a state that the main switch and the synchronous switch are simultaneously turned on,

wherein the detection circuit monitors a driving signal that drives at least one of the main switch and the synchronous switch, and detects a voltage across one of the main switch and the synchronous switch to detect a state in which the main switch and the synchronous switch are simultaneously turned on.

9. A switching regulator according to claim 8, wherein the switching regulator further comprises detection result output that outputs a detection result of the detection circuit.

10. A switching regulator according to claim 8, wherein the switching regulator further comprises an operation stop circuit that stops a conversion operation of the switching regulator in a case where the main switch and the synchronous switch are simultaneously turned on.

11. A switching regulator according to claim 8, wherein the detection circuit monitors at least one of the main switch and the synchronous switch.

12. A switching regulator according to claim 8, wherein the detection circuit monitors a direction of a current conducting through the synchronous switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

13. A switching regulator according to claim 8, wherein the detection circuit monitors a magnitude of a current conducting through the main switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

14. A switching regulator control circuit, comprising:

a first switch connected in series to an inductor;

a second switch disposed between a connecting point of the first switch with the inductor and a ground point where the first switch and the second switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a detection circuit that detects when the first switch and the second switch are simultaneously turned on,

wherein the detection circuit monitors a driving signal that drives at least one of the first switch and the second switch, and detects a voltage across one of the first switch and the second switch to detect the state in which the first switch and the second switch are simultaneously turned on.

15. A monitor circuit for a switching regulator, comprising:

a main switch; and

a synchronous switch, both of which are alternately turned on so that a voltage of a DC electric power is transformed and output, the monitor circuit comprising a detection circuit that detects a state that the main switch and the synchronous switch are simultaneously turned on,

wherein the detection circuit monitors a driving signal that drives at least one of the main switch and the synchronous switch, and detects a voltage across one of the main switch and the synchronous switch to detect a state in which the main switch and the synchronous switch are simultaneously turned on.

16. A monitor circuit according to claim 15, wherein the monitor circuit further comprises a detection result output that outputs a detection result of the detection circuit.

17. A monitor circuit according to claim 15, wherein the monitor circuit further comprises an operation stop circuit that stops a conversion operation of the switching regulator in a case where the main switch and the synchronous switch are simultaneously turned on.

18. A monitor circuit according to claim 15, wherein the detection circuit monitors at least one of the main switch and the synchronous switch.

19. A monitor circuit according to claim 15, wherein the detection circuit monitors a direction of a current conducting through the synchronous switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

20. A monitor circuit according to claim 15, wherein the detection circuit monitors a magnitude of a current conducting through the main switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

21. A monitor circuit for a switching regulator control circuit, comprising:

a first switch connected in series to an inductor;

a second switch disposed between a connecting point of the first switch with the inductor and a ground point where the first switch and the second switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a detection circuit that detects when the first switch and the second switch are simultaneously turned on,

wherein the detection circuit monitors a driving signal that drives at least one of the first switch and the second switch, and detects a voltage across one of the first switch and the second switch to detect the state in which the first switch and the second switch are simultaneously turned on.

22. An electronic equipment, comprising:

a switching regulator;

a main switch;

a synchronous switch, where the main switch and the synchronous switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a detection circuit that detects when the main switch and the synchronous switch are simultaneously turned on, wherein the electronic equipment is operative with an electronic power from the switching regulator,

wherein the detection circuit monitors a driving signal that drives at least one of the main switch and the synchronous switch, and detects a voltage across one of the main switch and the synchronous switch to detect a state in which the main switch and the synchronous switch are simultaneously turned on.

23. An electronic equipment according to claim 22, wherein the electronic equipment further comprises a display unit that displays that the main switch and the synchronous switch are simultaneously turned on.

24. An electronic equipment according to claim 22, wherein the electronic equipment further comprises an operation stop circuit that stops a conversion operation of the switching regulator in a case where the main switch and the synchronous switch are simultaneously turned on.

25. An electronic equipment according to claim 22, wherein the detection circuit monitors at least one of the main switch and the synchronous switch.

26. An electronic equipment according to claim 22, wherein the detection circuit monitors a direction of a current conducting through the synchronous switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

27. An electronic equipment according to claim 22, wherein the detection circuit monitors a magnitude of a current conducting through the main switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

28. An electronic equipment, comprising:

a switching regulator, comprising

a first switch;

an inductor which is connected in series with the first switch;

a second switch disposed between a connecting point of the first switch with the inductor and a ground point, in which the first switch and the second switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

a detection circuit that detects a state that the first switch and the second switch are simultaneously turned on, wherein the electronic equipment is operative with an electronic power from the DC—

DC converter,

wherein the detection circuit monitors a driving signal that drives at least one of the first switch and the second switch, and detects a voltage across one of the first switch and the second switch to detect the state in which the first switch and the second switch are simultaneously turned on.

29. A method of monitoring a switching regulator, comprising:

turning on a main switch;

turning on a synchronous switch, wherein the main switch and the synchronous switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

detecting a state that the main switch and the synchronous rectifying switch are simultaneously turned on is detected,

wherein the detecting monitors a driving signal driving at least one of the main switch and the synchronous switch, and detects a voltage across one of the main switch and the synchronous switch to detect a state in which the main switch and the synchronous switch are simultaneously turned on.

30. A method of monitoring a switching regulator according to claim 29, further comprising displaying in accordance with the detecting, that the main switch and the synchronous switch are simultaneously turned on.

31. A method of monitoring a switching regulator according to claim 29, wherein a conversion operation of the switching regulator is stopped in accordance with the detecting.

32. A method of monitoring a switching regulator according to claim 29, wherein the detecting monitors at least one of the main switch and the synchronous switch.

33. A method of monitoring a switching regulator according to claim 29, wherein the detecting monitors a direction of a current conducting through the synchronous switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

34. A method of monitoring a switching regulator according to claim 29, wherein the detecting monitors a magnitude of a current conducting through the main switch to detect a state that the main switch and the synchronous switch are simultaneously turned on.

35. A method of monitoring a switching regulator, comprising:

turning on a first switch and an inductor which are connected in series;

turning on a second switch disposed between a connecting point of the first switch with the inductor and a ground point, wherein the first switch and the second switch are alternately turned on so that a voltage of a DC electric power is transformed and output; and

detecting a voltage across one of the first switch and the second switch to detect a state in which the first switch and the second switch are simultaneously turned on.