Multiple output level power supply with overpower detection circuit

• US 5,724,026 A
• Filed: 04/24/1996
• Issued: 03/03/1998
• Est. Priority Date: 04/24/1996
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Allen, Jonathan Michael
• Primary Examiner(s): Mullen, Thomas
• Assistant Examiner(s): Edwards, Jr., Timothy
• Application Number:
  US08/639,917
• Time in Patent Office: 678 Days
• Field of Search: 323/267, 307/31-34, 307/82, 340/635, 340/636, 364/483, 364/482
• US Class Current: 340/635
• CPC Class Codes: H02H 3/42 responsive to product of voltage and current

Abstract

A multiple output level power supply is provided having an overpower detection circuit. The power supply provides multiple DC voltage output levels. A differential amplifier coupled to each DC voltage output level of the power supply is then utilized to generate a signal which is representative of the power output at each of the multiple voltage levels. The output of each differential amplifier is then coupled to a summer which generates a signal representative of the total power output from the multiple outputs of the power supply. A comparison of the total power output signal and a reference signal selected to be representative of the maximum desired power output may then be utilized to efficiently provide an indication of an overpower condition within the power supply.

Claims

1. An improved power supply comprising:

a DC power supply for providing a plurality of diverse DC voltage output levels;

a power indication circuit coupled to said DC power supply for generating a plurality of power output signals, each of said plurality of power output signals representative of the power output at one of said plurality of diverse DC voltage output levels; and

a summation circuit coupled to said power indication circuit for generating a total power output signal representative of the total power output from selected ones of said plurality of diverse DC voltage output levels of said DC power supply wherein overpower condition may be detected.

2. The improved power supply according to claim 1, further including a plurality of current sense resistors each coupled to said DC power supply at one of said plurality of diverse DC voltage output levels.

3. The improved power supply according to claim 2, wherein said power indication circuit comprises a plurality of differential amplifiers each coupled to one of said plurality of current sense resistors.

4. The improved power supply according to claim 1, wherein said summation circuit further includes a maximum total power output reference signal.

5. The improved power supply according to claim 4, wherein said summation circuit further includes a comparator circuit for comparing said total power output signal with said maximum total power output reference signal.

6. The improved power supply according to claim 5, further including an error indication signal generation circuit coupled to said comparator circuit for generating an error indication signal in response to said total power output signal exceeding said maximum total power output reference signal.

7. An improved computer system power supply comprising:

a DC power supply for providing a plurality of diverse DC voltage output levels;

a plurality of computer subsystem components, each of said plurality of computer subsystem components requiring at least one of a plurality of diverse DC voltage output levels;

a power indication circuit coupled to said DC power supply for generating a plurality of power output signals, each of said plurality of power output signals representative of the power output at one of said plurality of diverse DC voltage output levels; and

a summation circuit coupled to said power indication circuit for generating a total power output signal representative of the total power output from selected ones of said plurality of diverse DC voltage output levels of said DC power supply wherein overpower condition may be detected.

8. The improved power supply according to claim 7, further including a plurality of current sense resistors each coupled to said DC power supply at one of said plurality of diverse DC voltage output levels.

9. The improved power supply according to claim 8, wherein said power indication circuit comprises a plurality of differential amplifiers each coupled to one of said plurality of current sense resistors.

10. The improved power supply according to claim 7, wherein said summation circuit further includes a maximum total power output reference signal.

11. The improved power supply according to claim 10, wherein said summation circuit further includes a comparator circuit for comparing said total power output signal with said maximum total power output reference signal.

12. The improved power supply according to claim 11, further including an error indication signal generation circuit coupled to said comparator circuit for generating an error indication signal in response to said total power output signal exceeding said maximum total power output reference signal.