Start circuit for a switched mode power supply

• US 5,282,126 A
• Filed: 08/03/1992
• Issued: 01/25/1994
• Est. Priority Date: 08/01/1991
• Status: Expired due to Fees

• Current Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Original Assignee: US Philips Corporation (Koninklijke Philips N.V.)
• Inventors: Husgen, Theo
• Primary Examiner(s): Sterrett, J. L.
• Application Number:
  US07/924,277
• Time in Patent Office: 540 Days
• Field of Search: 323/901, 323/222, 323/282, 363/20, 363/21, 363/49, 363/97, 363/131
• US Class Current: 363/49
• CPC Class Codes: H02M 1/0006 Arrangements for supplying an adequate voltage to the control circuit of converters
• CPC Class Codes: H02M 1/009 having two or more independently controlled outputs for DC-DC converter with intermediate AC H02M3/33561
• CPC Class Codes: H02M 1/36 Means for starting or stopping converters
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: Y10S 323/901 Starting circuits

Abstract

A circuit arrangement, which includes a switched-mode power supply energized by a source and which is controlled by a control circuit. The switched-mode power supply supplies the control circuit with energy during operation. The circuit also comprising a starter circuit for applying a supply current to the control circuit when the arrangement is put into operation. A particularly simple and inexpensive construction is obtained in that the starter circuit comprises a capacitive voltage divider which is fed directly by the source and is provided with a tapping wherefrom the supply current is derived via a rectifier element.

Claims

1. A circuit arrangement, comprising:

a switched-mode power supply (SMPS) a source for feeding the SMPS and a control circuit for controlling the SMPS, which SMPS supplies the control circuit with energy during operation, and a starter circuit for applying a supply current to the control circuit when the circuit arrangement is put into operation, characterized in that the starter circuit comprises a capacitive voltage divider which is connected directly to the source and which comprises a tapping wherefrom the supply current is derived via a rectifier element.

2. A circuit arrangement as claimed in claim 1, further comprising second rectifier element of a polarity opposing that of the source and connected between a terminal of the source and the tapping.

3. A circuit arrangement as claimed in claim 1 wherein the connection from the starter circuit to the control circuit comprises a limiting impedance.

4. A circuit arrangement as claimed in claim 2, wherein the SMPS comprises a boost regulator, including a series connection of an inductance and a switching element wherefrom, via a third rectifier element, a voltage is derived for feeding a load, the capacitive voltage divider being connected parallel to the load.

5. A circuit arrangement as claimed in claim 2, wherein the connection from the starter circuit to the control circuit comprises a limiting impedance.

6. A circuit arrangement as claimed in claim 1, wherein the SMPS comprises a boost regulator including a series connection of an inductance and a switching element wherefrom, via a second rectifier element, a voltage is derived for feeding a load, the capacitive voltage divider being connected parallel to the load.

7. A circuit arrangement as claimed in claim 5, wherein the SMPS comprises a boost regulator including a series connection of an inductance and a switching element wherefrom, via a third rectifier element, a voltage is derived for feeding a load, the capacitive voltage divider being connected parallel to the load.