Programmable AC/DC power supply

• US 7,148,659 B2
• Filed: 06/20/2003
• Issued: 12/12/2006
• Est. Priority Date: 06/20/2003
• Status: Expired due to Fees

• Current Assignee: Comarco Wireless Systems LLC (AppBrilliance, Inc.)
• Original Assignee: Comarco Wireless Technologies Incorporated (Comarco Incorporated)
• Inventors: Lanni, Thomas W.
• Primary Examiner(s): Vu, Bao Q.
• Application Number:
  US10/600,262
• Publication Number:
  US 20040257835A1
• Time in Patent Office: 1,271 Days
• Field of Search: 363/142, 363/24, 363/26, 363/133, 363/134, 307/64, 307/66, 307/72, 307/73, 307/75
• US Class Current: 363/142
• 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: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• 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 programmable AC/DC power converter receives a plurality of input voltages and outputs a single voltage from an input voltage system. A transformer receives the single voltage. One of the plurality of input voltages is provided at a center tap of a secondary winding of the transformer. A transformed voltage is output. A rectifier receives the transformed voltage and outputs a DC voltage. A buck regulator receives a DC voltage, creates a regulated voltage, and outputs the regulated voltage and a regulated current to a portable appliance. A error correction system receives a programming signal and regulated signals and verifies that the regulated signal to programming signal ratio is within an acceptable range.

Claims

1. A power converter, comprising:

an input voltage system to receive an AC input voltage and to output a switched voltage;

a transformer, coupled to said input voltage system, to receive the switched voltage and to output an intermediate voltage, said transformer having a primary winding and a single secondary winding;

a boost circuit, coupled to the transformer, to receive the intermediate voltage and output an increased voltage; and

a buck regulator to receive the increased voltage, to generate a regulated voltage, and to output the regulated voltage as an output voltage and also to output a reference voltage in addition to the output voltage,

wherein said single secondary winding of said transformer is utilized as a boost inductor in the boost circuit and leakage inductance between the primary winding and the secondary winding is not utilized to boost the intermediate voltage to the output voltage.

2. The power converter of claim 1, wherein the power converter is capable of receiving a DC input voltage.

3. The power converter of claim 2, wherein the DC input voltage is input simultaneously with the AC input voltage.

4. The power converter of claim 1, further including an error correction system to receive a programming voltage and the regulated voltage, and to output a correction signal to the buck regulator based on a desired ratio between the programming voltage and the regulated voltage.

5. The power converter of claim 1, further including an error correction system to receive a programming current and a regulated current, and to output a correction signal to the buck regulator based on a ratio between the programming current and the regulated current.

6. The power converter of claim 1, wherein the input voltage system includes,

a voltage rectifying system to receive the AC input voltage and to output a rectified input voltage,

a driver to supply a driving signal with a duty cycle, and

a switching device to receive the rectified input voltage and the driving signal, to utilize the duty cycle of the driving signal to turn on and off the switching device to produce a switched voltage that is input to the primary winding of the transformer.

7. The power converter of claim 2, wherein the DC input voltage is provided from the group consisting of an airplane, a car, and a battery.

8. A power converter capable of receiving an AC input voltage and a DC input voltage, comprising:

a first capacitor, coupled to the DC input voltage, which is charged to the DC input voltage;

a transformer, coupled to a primary switching circuit and utilized if an AC input voltage is supplied, said transformer having a primary winding and a secondary winding where the secondary winding includes a center tap to separate the secondary winding into a first autowinding and a second autowinding, the DC input voltage being connected to the center tap of the secondary winding of the transformer; and

a control circuit coupled to switching devices, the switching devices coupled to the secondary winding, wherein the control circuit and the switching devices control the first autowinding and the second autowinding to charge a second capacitor to a DC voltage, wherein the DC input voltage and the DC voltage are added together to create an increased voltage at a first node.

9. The power converter of claim 8, wherein the AC input voltage is input to the power converter simultaneously with the DC input voltage.

10. The power converter of claim 8, further including a buck regulator to receive the increased voltage, to generate a regulated voltage, and to output the regulated voltage as an output voltage.

11. The power converter of claim 10, further including a voltage error system to receive a programming voltage and the regulated voltage, and to output a voltage correction signal to the buck regulator based on the ratio between the programming voltage and the regulated voltage.

12. The power converter of claim 10, further including an error correction system to receive a programming current and a regulated current, and to output a correction signal to the buck regulator based on a ratio between the programming current and the regulated current.

13. A method to output a regulated voltage from a power converter, comprising:

receiving an AC input voltage at an input voltage system and outputting therefrom a switched voltage;

receiving the switched voltage at a transformer, the transformer including a primary winding and a single secondary winding;

outputting an intermediate voltage from the transformer;

receiving the intermediate voltage at a boost circuit coupled to the transformer;

outputting an increased voltage from the boost circuit;

receiving the increased voltage at a buck regulator;

creating a regulated voltage at the buck regulator; and

outputting the regulated voltage and a regulated current as an output voltage and an output current and also outputting a separate reference voltage,

wherein the single secondary winding of the transformer is utilized as a boost inductor in the boost circuit and leakage inductance between the primary winding and the single secondary winding of the transformer is not utilized to boots the intermediate voltage to the increased voltage.

14. The method of claim 13, further including receiving a programming signal at an error correction system;

receiving regulated signals at the error correction subsystem;

comparing the programming signal with one of the regulated signals to determine if the one of the regulated signals to programming signal ratio is within an acceptable range; and

outputting a correction signal if the one of the regulated signals to programming signal ratio is outside the acceptable range.

15. The method of claim 14, wherein the programming signal is a voltage programming signal and the one of the regulated signals is a regulated voltage.

16. The method of claim 14, wherein the programming signal is a current programming signal and the one of the regulated signals is a regulated current.

17. A method to output a regulated voltage from a power converter that is capable of receiving an AC input voltage and a DC input voltage, comprising:

directly receiving a DC input voltage at a center tap of a secondary winding of the transformer, the transformer also including a primary winding, the center tap of the transformer separating the secondary winding of the transformer into a first autowinding and a second autowinding;

charging a first capacitor to the DC input voltage by coupling the DC input voltage across the first capacitor;

charging a second capacitor to a DC voltage by utilizing a control circuit and switching devices to control the first autowinding and the second autowinding of the transformer to apply the input DC voltage across the second capacitor; and

adding, at a first node, the DC input voltage and DC voltage to generate an increased voltage.

18. The method of claim 17, further including receiving the increased voltage at a buck regulator;

creating a regulated voltage at the buck regulator; and

outputting the regulated voltage and a regulated current as an output voltage and an output current.

19. The method of claim 18, further including receiving a programming signal at an error correction system;

receiving regulated signals at the error correction system;

comparing the programming signal with one of the regulated signals to determine if the one of the regulated signals to programming signal ratio is within an acceptable range; and

outputting a correction signal if the one of the regulated signals to programming signal ratio is outside the acceptable range.

20. The method of claim 19, wherein the programming signal is a voltage programming signal and the one of the regulated signals is a regulated voltage.

21. The method of claim 19, wherein the programming signal is a current programming signal and the one of the regulated signals is a regulated current.

22. A power converter capable of receiving an AC input voltage and a DC input voltage, comprising:

a transformer, coupled to a primary switching circuit, said transformer having a primary winding and a secondary winding, the secondary winding including a center tap to separate the secondary winding into a first autowinding and a second autowinding, the DC input voltage being directly applied to the center tap of the secondary winding of the transformer; and

a control circuit coupled to a plurality of switching devices, the plurality of switching devices coupled to the secondary winding, wherein the control circuit and the switching devices control the first autowinding and the second autowinding to output an increased DC voltage, the increased voltage being an addition of a voltage across the first autowinding and a voltage across the second autowinding.

23. The power converter of claim 22, further including a buck regulator to receive the increase voltage, to generate a regulated voltage, and to output the regulated voltage as an output voltage and also to output a reference voltage.