Universal input voltage power supply

• US 5,126,652 A
• Filed: 04/15/1991
• Issued: 06/30/1992
• Est. Priority Date: 04/15/1991
• Status: Expired due to Term

• Current Assignee: Square D Company (Schneider Electric SE)
• Original Assignee: Square D Company (Schneider Electric SE)
• Inventors: Carlin, Charles K.
• Primary Examiner(s): Wong, Peter S.
• Application Number:
  US07/685,353
• Time in Patent Office: 442 Days
• Field of Search: 363/89, 363/126, 323/266, 323/267, 323/282-287, 323/908, 323/901
• US Class Current: 323/267
• CPC Class Codes: H02M 1/10 Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc
• CPC Class Codes: Y10S 323/908 Inrush current limiters

Abstract

The power supply of the present invention is designed to operate over a wide range of both ac and DC input voltages and frequencies from 0-400 Hz. The power supply also provides two DC low voltage outputs, one for devices that do not require a high degree of regulation and one for devices that do require a high degree of regulation. The power supply also includes a power-up inrush clamp to limit high start up currents to approximately two times the nominal switching current. The primary switching transistor of the power supply is controlled by a dynamic feedback circuit which works interactively to increases the switching speed of the primary switching transistor.

Claims

1. An universal input voltage DC power supply connected to an AC or Dc source voltage, said power supply comprising:

a pair of input terminals for receiving the universal AC or DC voltage input;

a transient voltage suppression means connected across said input terminals for suppressing transient voltage spikes from the universal input source voltage;

a DC voltage rectifier means coupled to said transient voltage suppression means for providing a DC voltage to said power supply

a first high voltage transistor coupled to said DC voltage rectifier means for primary switching of the power supply;

a second high voltage transistor coupled to the base of said first high voltage transistor for controlling said first high voltage transistor;

a current storage means coupled to the collector of said firs high voltage transistor for supplying current to the load when said first high voltage transistor is turned off;

an inrush clamping means coupled to said current storage means for preventing high start-up currents from damaging said first high voltage transistor;

a dynamic feedback circuit connected between said inrush clamping means and the base of said second high voltage transistor for interactively speeding up the switching rate of said first high voltage transistor;

a first low voltage output connected to the current storage means for devices not requiring a high degree of regulation or low ripple voltage; and

a second low voltage output connected to the current storage means for devices requiring a higher degree of regulation and low ripple voltage.

2. The power supply of claim 1 wherein said current storage means comprises:

an inductor for storing current as magnetic field energy; and

a storage capacitor charged to a value determine by a Zener diode in parallel with said stroage capacitor.

3. The power supply of claim 2 wherein said inrush clamping means comprises:

a bypass diode for permitting the inrush current to bypass said storage capacitor and said Zener diode and flow directly to said dynamic feedback circuit for controlling the switching of said first high voltage transistor.

4. The power supply of claim 3 wherein said first high voltage transistor is a high voltage PNP bipolar transistor.

5. The power supply of claim 4 wherein said second high voltage transistor is a high voltage N-channel MOSFET transistor

6. The power supply of claim 5 wherein said dynamic feedback circuit comprises:

a sensing resistor for sensing load current and converting the load current into a ripple voltage inserted into said dynamic feedback circuit;

a plurality of low voltage transistors connected such that the output of one of said transistors influences the state of another of said transitors;

a reistor divider network activated by said low voltage transistor, said resitor divider network interacts with said low voltage transitors to increase the switching speed of said high voltage transistors.

7. The power supply of claim 6 wherein one of said low voltage transistors is a low voltage N-channel MOSFET transistor and wherein the maximum gate voltage threshold of said low voltage N-channel MOSFET transistor is less than the minimum gate voltage threshold of said high voltage P-channel MOSFET transistor.

8. The power supply of claim 6 wherein said ripple current initiates the power supply switching process.

9. The power supply of claim 1 wherein said first low voltage output is taken across said storage capacitor.

10. The power supply of claim 1 wherein said second low voltage ouput is taken across a low drop-out voltage regulator.

11. The power supply of claim 1 wherein said first high voltage transistor is a high voltage N-channel MOSFET transistor.