DC to DC converter for decreasing switching loss according to the turn-on/turn-off state of a switch

• US 7,630,219 B2
• Filed: 01/10/2007
• Issued: 12/08/2009
• Est. Priority Date: 01/10/2006
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Jin-hyung
• Primary Examiner(s): Sterrett; Jeffrey L
• Application Number:
  US11/651,588
• Publication Number:
  US 20070159857A1
• Time in Patent Office: 1,063 Days
• Field of Search: 363/21.12, 363/21.16, 363/97, 363/131
• US Class Current: 363/21.16
• CPC Class Codes: H02M 1/34 Snubber circuits
• CPC Class Codes: H02M 1/346 Passive non-dissipative snubbers
• CPC Class Codes: H02M 3/335 using semiconductor devices only
• 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

A direct current (DC) to DC converter is provided. The DC to DC converter includes: a transformer which comprises a primary winding which is connected in series with an input voltage and a secondary winding which generates induced current when the input voltage is applied to the primary winding; a switching part which is connected to the primary winding and performs a switching operation according to a predetermined control signal; a first delay part which delays an increasing rate of voltage between open nodes according to a turned-off state of the switching part and supplies a discharge current when the switching part is turned-on; and a second delay part which delays current flow in the switching part when the first delay part discharges the current when the switching part is turned-on.

Claims

1. A direct current (DC) to DC converter comprising:

a transformer which comprises a primary winding which is connected in series with an input voltage, and a secondary winding which generates an induced current when the input voltage is applied to the primary winding;

a switching part which is connected to the primary winding and performs a switching operation according to a control signal;

a first delay part which delays an increasing rate of voltage between open nodes according to a turned-off state of the switching part and supplies a discharge current when the switching part is turned-on;

a second delay part which delays a current flow in the switching part when the first delay part discharges the current when the switching part is turned-on; and

a switching control part which senses a voltage output from the primary winding and applies a turn-on control signal to the switching part if the voltage is a minimum voltage when the switching part is turned-off.

2. The DC to DC converter according to claim 1, wherein the switching part comprises a metal-oxide semiconductor field effect transistor (MOSFET).

3. The DC to DC converter according to claim 1, wherein the first delay part comprises a capacitor having a first side which is connected to the primary winding and the switching part and which is charged with voltage from the primary winding when the switching part is turned-off and discharges the charged voltage to the switching part when the switching part is turned-on.

4. The DC to DC converter according to claim 3, wherein the second delay part comprises an inductor which is connected to a ground of the switching part and a second side of the capacitor and coupled with the primary winding and delays the current flow in the switching part when a current is discharged by the capacitor when the switching part is turned-on.

5. The DC to DC converter according to claim 4, wherein the inductor is wound in a direction opposite to a winding direction of the primary winding.

6. The DC to DC converter according to claim 4, wherein the second delay part comprises a second diode having an anode terminal which is connected to the inductor and a cathode terminal which is connected to one side of the capacitor and an anode terminal of a first diode.

7. The DC to DC converter according to claim 3, wherein the first delay part further comprises a first diode having an anode terminal which is connected to a second side of the capacitor and a cathode terminal which is connected to the input voltage to control a current flow.

8. The DC to DC converter according to claim 7, wherein the second delay part comprises an inductor which is connected to a ground of the switching part and a second side of the capacitor and coupled with the primary winding and delays the current flow in the switching part when a current is discharged by the capacitor when the switching part is turned-on.

9. The DC to DC converter according to claim 8, wherein the second delay part comprises a second diode having an anode terminal which is connected to the inductor and a cathode terminal which is connected to one side of the capacitor and the anode terminal of the first diode.

10. The DC to DC converter according to claim 8, wherein the inductor is wound in an opposite direction to the primary winding.

11. The DC to DC converter according to claim 1, wherein the transformer comprises a flyback transformer.