Compact multiple output power supply

• US 6,198,642 B1
• Filed: 10/19/1999
• Issued: 03/06/2001
• Est. Priority Date: 10/19/1999
• Status: Expired due to Fees

• Current Assignee: Tracewell Power, Inc.
• Original Assignee: Tracewell Power, Inc.
• Inventors: Kociecki, John
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Laxton, Gary L.
• Application Number:
  US09/420,664
• Time in Patent Office: 504 Days
• Field of Search: 307/11, 307/31, 307/38, 307/33, 307/150, 307/82, 307/155, 363/65, 363/37, 363/141, 363/144, 363/127, 361/704, 361/707, 361/715, 361/741
• US Class Current: 363/37
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 1/008 Plural converter units for generating at two or more independent and non-parallel outputs, e.g. systems with plural point of load switching regulators
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• CPC Class Codes: H02M 3/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• 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 compact multiple output power supply which has a circuit architecture with distinct primary and secondary circuit domains. Within the secondary circuit domain, a distribution bus of relatively low constant voltage supplies power inputs to d.c.-to-d.c. converters providing regulated outputs and operating independently of each other. Because of the secondary circuit domain topology, surface mount components are made available in conjunction with relatively simple converter circuitry. Heat management within the compact housing of the power supply is achieved through the utilization of linear driven air flows in combination with employment of heat sinks extending to the heat sink configured cover of the housing. Additionally, the highest heat generation components are positioned rearwardmost within the driven air path.

Claims

1. A power supply connectable with a power input to provide multiple regulated outputs, comprising:

an input treatment network responsive to said power input to derive an interim voltage output of first value within a primary circuit domain;

an inverter network within said primary circuit domain, responsive to said interim voltage and responsive to an inverter control input to derive an unregulated alternating voltage output of second value less than said first value at an output within a secondary circuit domain;

an inverter control network coupled with said inverter network and deriving said inverter control input;

a rectifier network within said second circuit domain responsive to said alternating voltage output to derive a distribution output at a d.c. voltage level corresponding with said alternating voltage output;

a first d.c.-to-d.c. converter, within said secondary circuit domain responsive to said distribution output and to a first converter enable control input to derive a first one of said regulated outputs at a first voltage value;

a second d.c.-to-d.c. converter, within said secondary circuit domain, responsive to said distribution output and to a second converter enable input to derive a second one of said regulated outputs at a second voltage value independent of said first one of said outputs; and

control circuit within said secondary circuit domain, electrically coupled with said first and second d.c.-to-d.c. converters and deriving said first and second converter enable control inputs.

2. The power supply of claim 1 in which said first and second d.c.-to-d.c. converters are comprised of circuits formed with surface mount components.

3. The power supply of claim 1 in which said distribution output d.c. voltage level is about 12 volts.

4. The power supply of claim 1 including a fuse intermediate said input treatment network and said inverter network.

5. Power supply apparatus for providing regulated d.c. outputs to an electrical system supported by a rack having an accessible forward portion and a power input comprising:

a housing supported within said rack having an accessible forward end with a forward air transfer opening located at said rack forward portion, said housing extending longitudinally rearwardly to a rearward end with a rearward air transfer opening and having a top cover formed of thermally conductive material, a bottom and oppositely disposed sides to define an internal cavity within which is a generally longitudinally directed driven air path;

a motherboard circuit board having an upwardly disposed surface supporting a main printed circuit, mounted within said cavity adjacent to and in parallel with said bottom;

an input treatment network responsive to said power input to derive an interim voltage output of first value within a primary circuit domain;

an inverter network within said primary circuit domain, responsive to said interim voltage and to an inverter control input to derive an unregulated alternating voltage output of second value less than said first value at an output within a secondary circuit domain;

an inverter control network within said primary circuit domain coupled with said inverter network and deriving said inverter control input;

a rectifier network within said second circuit domain, responsive to said alternating voltage output to derive a distribution output at a d.c. voltage level corresponding with said alternating voltage output;

a first d.c.-to-d.c. converter within said secondary circuit domain, having first power switching transistors, responsive to said distribution output and to a first converter enable control input to derive a first one of said regulated d.c. outputs at a first voltage value;

a second d.c.-to-d.c. converter, within said secondary circuit domain, having second power switching transistors, responsive to said distribution output and to a second converter enable input to derive a second one of said regulated d.c. outputs at a second voltage value;

a control circuit within said secondary circuit domain, electrically coupled with said first and second d.c.-to-d.c. converters and deriving said first and second converter enable control inputs;

a first daughter circuit board having front and back oppositely disposed faces spaced apart a circuit board thickness and a first connector carrying support edge of predetermined profile, and being supported by said motherboard circuit board at said first support edge in an orientation normal to said upper surface and aligned in parallel with said driven air path to define air pathways passing adjacent said front and back faces;

said first d.c.-to-d.c. converter being formed with surface mount components attached to said first daughter circuit board front face and electrically coupled from said first connector carrying support edge with said distribution output and said control circuit through said main printed circuit;

a second daughter circuit board having front and back oppositely disposed faces spaced apart a said circuit board thickness and a second connector carrying support edge of predetermined profile, and being supported by said motherboard circuit board at said second support edge in a orientation normal to said upper surface and aligned in parallel with said driven air path to define air pathways passing adjacent said front and back faces; and

said second d.c.-to-d.c. converter being formed with surface mount components attached to said second daughter circuit board front face and electrically coupled from said second connector carrying support edge with said distribution output and said control circuit through said main printed circuit.

6. The power supply apparatus of claim 5 in which:

said first and second daughter circuit boards are configured having a plurality of metal covered channels extending from said front face to said back face underneath the mounting positions of said respective first and second power switching transistors and being in thermal exchange communication therewith; and

including first and second flat metal heat sinks, each having an inner surface attached to a said back face in thermal exchange communication with said metal covered channels.

7. The power supply apparatus of claim 6 in which said plurality of channels are filled with a thermally conductive metal.

8. The power supply apparatus of claim 5 in which said circuit board thickness of said first and second daughter circuit boards is about 0.047 inch.

9. The power supply apparatus of claim 6 in which:

said first power switching transistors are mounted upon said first daughter circuit board in spaced apart paired adjacency, each such first power switching transistor having an outwardly disposed surface;

including a thermally conductive connector plate abuttably positioned against each said outwardly disposed surface; and

a thermally conductive connector connecting said connector plate with said first flat metal heat sink through said first daughter circuit board.

10. The power supply apparatus of claim 5 in which:

said housing includes an upper rearward air transfer opening extending within said top cover forwardly from said rearward end;

including a multiple pin connector configured for circuit completing engagement with a corresponding connector of said electrical system, having a forwardly facing surface, a bottom surface supported adjacent said rearward end and a top surface spaced below said upper rearward air transfer opening to define a rearward air transfer passageway extending to said rearward air transfer opening and said upper rearward air transfer opening, and being in electrical communication with said main printed circuit;

a thermally conductive heat transfer component with a forward portion extending normally upwardly from said motherboard circuit board upwardly disposed surface adjacent said connector forwardly facing surface and a top portion extending in adjacency over said connector top surface;

including first and second blocking diode assemblies respectively coupled with said main printed circuit to receive said first and second regulated d.c. outputs and coupled in thermal exchange relationship with said heat transfer component forward portion; and

a thin sheet metal folded fin heat exchanger array mounted in heat exchange relationship with said heat transfer component top portion, having parallel channels aligned for receiving driven air passing within said rearward air transfer passageway and directing it through said rearward air transfer opening.

11. The power supply apparatus of claim 10 including a fan assemblage mounted within said housing at said forward air transfer opening and actuable to generate said driven air path moving from said forward air transfer opening through said internal cavity and outwardly from said rearward air transfer opening and said upper rearward air transfer opening.

12. The power supply apparatus of claim 10 in which said folded fin heat exchanger array is spaced in non-contacting relationship from said housing top cover and located in adjacency with said upper rearward air transfer opening.

13. The power supply apparatus of claim 5 in which:

said housing top cover is formed of thermally conductive material;

said input treatment network includes heat generating input treatment circuit components electrically coupled with said main printed circuit;

including an elongate, flat thermally conductive first heat transfer plate, having a top side connected in heat transfer relationship with said housing top cover, extending from said top cover to perpendicular adjacency with said motherboard circuit board upwardly disposed surface, having a first surface spaced from and parallel with a said housing side and said driven air path to define an air pathway therebetween, and having an oppositely disposed second surface within said driven air path; and

said heat generating input treatment circuit components being connected in heat transfer relationship with said first heat transfer plate.

14. The power supply apparatus of claim 11 in which:

said first heat generating input treatment circuit components are connected with said heat transfer plate first surface; and

said first heat transfer plate second surface is configured with an array of surface area enlarging longitudinally disposed serrations.

15. The power supply apparatus of claim 14 in which said heat generating input treatment circuit components comprise power switching transistors and diodes.

16. The power supply apparatus of claim 5 in which:

said housing top cover is formed of thermally conductive material;

said rectifier network comprises diodes which generate heat while deriving said distribution output;

including a flat, thermally conductive second heat transfer plate having a top side connected in heat transfer relationship with said housing top cover, extending from said top cover to perpendicular adjacency with said motherboard circuit board upwardly disposed surface, having a component mount surface aligned with said longitudinally directed driven air path; and

said diodes are coupled in heat transfer relationship with said component mount surface.

17. The power supply apparatus of claim 5 in which:

said input treatment network includes a plurality of hold-up capacitors chargeable from said interim voltage output; and

said holdup capacitors are supported upon said motherboard circuit board upwardly disposed surface, extend upwardly normally thereto and are linearly aligned in mutual adjacency longitudinally within and in parallel with said driven air path.

18. The power supply apparatus of claim 5 including:

a plurality of filter capacitors coupled with said distribution output; and

said filter capacitors are supported upon said motherboard circuit board upwardly disposed surface, extend upwardly normally thereto and are grouped within linearly aligned within and arrays in mutual adjacency, each such array being aligned in parallel with said longitudinally directed driven air path.

19. The power supply apparatus of claim 12 in which:

said first and second daughter circuit boards are configured having a plurality of metal covered channels extending from said front face to said back face underneath the mounting positions of said respective first and second power switching transistors and being in thermal exchange communication therewith, and

including first and second flat metal heat sinks, each having an inner surface attached to a said back face in thermal exchange communication with said metal covered channels.

20. The power supply apparatus of claim 19 including a fan assemblage mounted within said housing at said forward air transfer opening and actuable to generate said driven air path moving from said forward air transfer opening through said internal cavity and outwardly from said rearward air transfer opening and said upper rearward air transfer opening.

21. The power supply apparatus of claim 19 in which:

said housing top cover is formed of thermally conductive material;

said input treatment network includes heat generating input treatment circuit components electrically coupled with said main printed circuit;

including an elongate, flat thermally conductive first heat transfer plate, having a top side connected in heat transfer relationship with said housing top cover, extending from said top cover to perpendicular adjacency with said motherboard circuit board upwardly disposed surface, having a first surface spaced from and parallel with a said housing side and said driven air path to define an air pathway therebetween; and

having an oppositely disposed second surface within said driven air path; and

said heat generating input treatment circuit components being connected in heat transfer relationship with said first heat transfer plate.

22. The power supply apparatus of claim 21 in which:

said rectifier network comprises diodes which generate heat while deriving said distribution output;

including a flat, thermally conductive second heat transfer plate having a top side connected in heat transfer relationship with said housing top cover, extending from said top cover to perpendicular adjacency with said motherboard circuit board upwardly disposed surface, having a component mount surface aligned with said longitudinally directed driven air path; and

said diodes are coupled in heat transfer relationship with said component mount surface.

23. The power supply apparatus of claim 10 in which:

said housing top cover is formed of thermally conductive material;

said input treatment network includes heat generating input treatment circuit components electrically coupled with said main printed circuit;

including an elongate, flat, thermally conductive first heat transfer plate, having a top side connected in heat transfer relationship with said housing top cover, extending from said top cover to perpendicular adjacency with said motherboard circuit board upwardly disposed surface, having a first surface spaced from and parallel with a said housing side and said driven air path to define an air pathway therebetween, and having an oppositely disposed second surface within said driven air path; and

said heat generating input treatment circuit components being connected in heat transfer relationship with said first heat transfer plate.

24. The power supply apparatus of claim 13 in which:

said rectifier network comprises diodes which generate heat while deriving said distribution output;

including a flat, thermally conductive second heat transfer plate having a top side connected in heat transfer relationship with said housing top cover, extending [therefrom] from said top cover to perpendicular adjacency with said motherboard circuit board upwardly disposed surface, having a component mount surface aligned with said longitudinally directed driven air path; and

said diodes are coupled in heat transfer relationship with said component mount surface.

25. A power supply connectable with a power input to provide multiple regulated outputs and exhibiting an overall wattage power rating of predetermined value, comprising:

an input treatment network responsive to said power input to derive an interim voltage output of first value within a primary circuit domain;

an inverter network within said primary circuit domain, responsive to said interim voltage and responsive to an inverter control input to derive an alternating voltage output of second value less than said first value at an output within a secondary circuit domain;

an inverter control network coupled with said inverter network and deriving said inverter control input;

a rectifier network within said second circuit domain responsive to said alternating voltage output to derive a distribution output at a d.c. voltage level corresponding with said alternating voltage output;

a first d.c.-to-d.c. converter, within said secondary circuit domain responsive to said distribution output and to a first converter enable control input to derive a first one of said regulated outputs at a first voltage value;

a second d.c.-to-d.c. converter, within said secondary circuit domain, responsive to said distribution output and to a second converter enable input to derive a second one of said regulated outputs at a second voltage value independent of said first one of said outputs; and

a control circuit within said secondary circuit domain, electrically coupled with said first and second d.c.-to-d.c. converters and deriving said first and second converter enable control inputs said control circuit including a current detector network responsive to said alternating voltage output to derive a current signal corresponding with the value of current exhibited at said alternating voltage output, said current detector network being responsive to said current signal and to a comparison signal corresponding with said rating value to derive a limit signal when said current signal exceeds said comparison signal, and is responsive in the presence of said limit signal to effect termination of said first and second converter enable control inputs.

26. The power supply of claim 25 in which:

said control circuit includes a limit indicator energizable to provide a perceptible output; and

said control circuit is responsive to energize said limit indicator in the presence of said limit signal.

27. The power supply of claim 25 in which said control circuit is responsive at the initiation of said limit signal to delay said termination of said first and second converter enable outputs for a predetermined delay interval.

28. The power supply of claim 27 in which said predetermined delay interval is about ten seconds.

29. The power supply of claim 25 in which:

said input treatment network includes an a.c. to d.c. boost converter responsive to said power input to effect power factor correction and to derive said interim voltage output of first value;

said inverter network includes a transformer stage having a secondary winding conveying said alternating voltage output of said second value, and a filter inductor responsive to said rectifier network output; and

said current detector network is configured as an integrator responsive to current flow of given value within said filter inductor to derive said current signal.

30. The power supply of claim 29 in which:

said distribution output d.c. voltage level is substantially a constant voltage value in the absence of variations of said power input; and

said current signal is linearly correlatable with the product of said given value of current flow and said constant voltage value.

31. A power supply connectable with a power input to provide multiple regulated outputs, comprising:

an input treatment network responsive to said power input to derive an interim voltage output of first value within a primary circuit domain;

an inverter network within said primary circuit domain, responsive to said interim voltage and responsive to an inverter control input to derive an alternating voltage output of second value less than said first value at an output within a secondary circuit domain;

an inverter control network coupled with said inverter network and deriving said inverter control input;

a rectifier network within said second circuit domain responsive to said alternating voltage output to derive a distribution output at a d.c. voltage level corresponding with said alternating voltage output;

a first d.c.-to-d.c. converter, within said secondary circuit domain responsive to said distribution output and to a first converter enable control input to derive a first one of said regulated outputs at a first voltage value;

a second d.c.-to-d.c. converter, within said secondary circuit domain, responsive to said distribution output and to a second converter enable input to derive a second one of said regulated outputs at a second voltage value independent of said first one of said outputs; and

a control circuit within said secondary circuit domain, electrically coupled with said first and second d.c.-to-d.c. converters and deriving said first and second converter enable control inputs said control circuit including a voltage monitoring network responsive to said distribution output d.c. voltage level and to a reference corresponding with a predetermined threshold value of voltage for said distribution output to effect termination of said first and second converter enable outputs when said d.c. voltage level at said distribution output is below said threshold value.

32. The power supply of claim 31 in which:

said control circuit includes an input status indicator energizable to provide a perceptible output; and

said control circuit is responsive to energize said input status indicator in the presence of said first and second converter enable outputs.