Switching converter

• US 20030178890A1
• Filed: 04/02/2003
• Published: 09/25/2003
• Est. Priority Date: 10/02/2000
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG Osterreich (Siemens AG)
• Inventors: Kranister, Andreas, Rothmayer, Thomas, Weinmeier, Harald
• Granted Patent: US 7,138,731 B2
• Time in Patent Office: Days
• US Class Current: 307/83
• CPC Class Codes: H02M 3/33561 having more than one ouput with independent control

Abstract

Switching converter to convert an input direct current (U_E) into at least one output direct current (U_A), wherein an internal auxiliary voltage (U_H1, U_H2) is derived from at least one auxiliary winding (W_H1, W_H2) of a transformer (Tr), a controllable load element (BAL) is provided for the output voltage, and a stop signal (s_s) can be fed to turn the output voltage of the switching converter ON/OFF, which is used to connect the load element (BAL) to the output direct current to such an extent that a short-circuit-like condition is produced, in which the output voltage (U_a) is adequately close to null, but the at least one auxiliary voltage (U_H1, U_H2) is adequately high to supply the units associated therewith.

Claims

1. Switching converter to convert an input direct current (U_E) into at least one output direct current (U_A), wherein a primary winding (W_P) of a transformer (Tr) may be connected via a controlled switch (S) to the input direct current (U_E), a control signal (s_a) with a variable pulse duty factor is fed to the switch by a control circuit (AST), and regulation is provided depending on secondary and/or primary currents or voltages by changing at least the pulse duty factor of the control signal, an internal auxiliary voltage (U_H1, U_H2) is derived from at least one auxiliary winding (W_H1, W_H2), a controllable load element (BAL) is provided for the output voltage, and a stop signal (s_s) can be fed to turn the output voltage of the switching converter ON/OFF,

characterized in that

the stop signal (s_s) is used to connect the load element (BAL) to the output direct current to such an extent that a short-circuit-like condition is produced, in which the output voltage (U_a) is adequately close to null, but the at least one auxiliary voltage (U_H1, U_H2) is adequately high to supply the units associated therewith.

2. Switching converter according to claim 1, characterized in that a load regulator (BAR), to which a signal (s_i) related to the output current (I_A) is supplied, is provided for the control of the load element (BAL).

3. Switching converter according to claim 2, characterized in that a signal (s_i) related to the current (i_i) through the load element (BAL) is supplied to the load regulator (BAR).

4. Switching converter according to one of claims 1 through 3, characterized in that the deviation between the auxiliary voltage (U_H2) and a reference voltage (U_ref) is fed as a control signal in the short-circuit-like condition of the control circuit (AST) triggered by the stop signal (s_s).

5. Switching converter according to one of claims 1 through 4, characterized in that the load element (BAL) is a controllable semiconductor.

6. Switching converter according to claim 5, characterized in that the load element (BAL) is a transistor.

7. Switching converter according to claim 1, characterized in that the load element (BAL) can be connected to the output voltage (U_a) using a switch (A, a) controlled by the stop signal (s_s).

8. Switching converter according to claim 7, characterized in that the controlled switch (A, a) is a relay.

9. Switching converter according to claim 7 or 8, characterized in that the load element (BAL) has a connectable resistor (R_L).