AC COUPLED SWITCHING POWER SUPPLY AND METHOD THEREFOR

• US 20100328973A1
• Filed: 06/26/2009
• Published: 12/30/2010
• Est. Priority Date: 06/26/2009
• Status: Abandoned Application

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Microchip Technology Incorporated
• Inventors: Caballero, Rex, Lynch, Scott, Choy, Benedict C.K.
• Application Number:
  US12/492,994
• Publication Number:
  US 20100328973A1
• Time in Patent Office: Days
• US Class Current: 363/52
• CPC Class Codes: H02M 7/2176 comprising a passive stage to generate a rectified sinusoidal voltage and a controlled switching element in series between such stage and the output

Abstract

A circuit for converting high voltage AC to low voltage DC has an input capacitor coupled an input AC source. A rectifier is coupled to the input capacitor. A switch is coupled to the rectifier. A voltage regulator is coupled to the switch. The voltage regulator regulates an output of the circuit by closing the switch when a rising edge of a rectified AC voltage is below an output voltage and opens the switch when the output voltage reaches a regulation voltage. A storage capacitor is coupled to the switch.

Claims

1. A circuit for converting high voltage AC to low voltage DC comprising:

an input capacitor coupled an input AC source;

a rectifier coupled to the input capacitor;

a switch coupled to the rectifier;

a voltage regulator coupled to the switch, the voltage regulator regulates an output of the circuit by closing the switch when a rising edge of a rectified AC voltage is below an output voltage and opens the switch when the output voltage reaches a regulation voltage; and

a storage capacitor coupled to the switch.

2. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 wherein the switch is a transistor.

3. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 wherein the switch is an N-channel transistor.

4. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 wherein the switch is an N-channel IGBT.

5. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 wherein the input capacitor acts as a capacitive divider with an output load.

6. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 further comprising a fuse coupled in series with the an input capacitor and the input AC source.

7. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 further comprising a varistor coupled to the input capacitor and the rectifier.

8. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 wherein the rectifier is a full bridge rectifier.

16. A circuit for converting high voltage AC to low voltage DC in accordance with claim 1 wherein the input capacitor is a film capacitor.

9. A circuit for converting high voltage AC to low voltage DC comprising:

an input capacitor coupled an input AC source, the input capacitor acing as a capacitive divider with an output load;

a full bridge rectifier coupled to the input capacitor;

a switch coupled to the full bridge rectifier;

a voltage regulator coupled to the switch, the voltage regulator regulates an output of the circuit by closing the switch when a rising edge of a rectified AC voltage is below an output voltage and opens the switch when the output voltage reaches a regulation voltage; and

a storage capacitor coupled to the switch.

10. A circuit for converting high voltage AC to low voltage DC in accordance with claim 9 wherein the switch is a transistor.

12. A circuit for converting high voltage AC to low voltage DC in accordance with claim 9 wherein the switch is an N-channel transistor.

13. A circuit for converting high voltage AC to low voltage DC in accordance with claim 9 wherein the switch is an N-channel IGBT.

14. A circuit for converting high voltage AC to low voltage DC in accordance with claim 9 further comprising a fuse coupled in series with the the input capacitor and the input AC source.

15. A circuit for converting high voltage AC to low voltage DC in accordance with claim 9 further comprising a varistor coupled to the input capacitor and the rectifier.

17. A circuit for converting high voltage AC to low voltage DC comprising:

an input capacitor coupled an input AC source, the input capacitor acing as a capacitive divider with an output load;

a full bridge rectifier coupled to the input capacitor;

a fuse coupled in series with the the input capacitor and the input AC source;

a varistor coupled to the input capacitor and the rectifier;

a switch coupled to the full bridge rectifier;

a voltage regulator coupled to the switch, the voltage regulator regulates an output of the circuit by closing the switch when a rising edge of a rectified AC voltage is below an output voltage and opens the switch when the output voltage reaches a regulation voltage; and

a storage capacitor coupled to the switch.

18. A circuit for converting high voltage AC to low voltage DC in accordance with claim 17 wherein the switch is a transistor.

19. A circuit for converting high voltage AC to low voltage DC in accordance with claim 17 wherein the switch is an N-channel transistor.

20. A circuit for converting high voltage AC to low voltage DC in accordance with claim 17 wherein the input capacitor is a film capacitor.