US5528149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Test circuit for back-up battery
Assignee: International Business Machines Corp
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Filing: 1994-12-23
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Granted: 1996-06-18
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Expires: 2014-12-23
Abstract
Abstract A test circuit for a back-up battery includes a main switch which connects a main power source to a load, and a diode which is interposed between a back-up battery and the load. The diode is reversed biased when the main power source supplies rated power to the load. To test the battery, the main switch is turned off such that the back-up battery supplies operating current to the load via the diode. During a test interval, the output voltage is monitored to determine if the battery is able to supply its rated voltage under load. After the test or if the battery fails to supply requisite voltage, the main switch is turned-on again.
Inventors
- 👤 Zhong X. Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:32
CPC Classifications
G; G01; G01R; G01R19/00; G01R19/165; G01R19/16533; G01R19/16538; G01R19/16542; H; H01; H01M; H01M10/00; H01M10/42; H01M10/44; H02; H02J; H02J9/00; H02J9/04; H02J9/06; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S320/00; Y10S320/18; Y10S320/21
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
123 words
A test circuit for a battery which backs-up and has lower rated voltage than a main power source, said circuit comprising: an input port for connection to the main power source; an output port for connection to a load; a main switch connected between the input and output ports; a battery connection port coupled to said output port; and means for turning off said main switch at a start of a battery test interval, supplying said load from said battery beginning at the start of and continuing during said battery test interval and determining if said battery supplies said load with at least a predetermined threshold voltage for the duration of said battery test interval, in which case said battery passes a test.
Claim 2
Dependent Claim
123 words
A test circuit for a battery which backs-up and has lower rated voltage than a main power source, said circuit comprising: an input port for connection to the main power source; an output port for connection to a load; a main switch connected between the input and output ports; a battery connection port coupled to said output port; and means for turning off said main switch at a start of a battery test interval, supplying said load from said battery beginning at the start of and continuing during said battery test interval and determining if said battery supplies said load with at least a predetermined threshold voltage for the duration of said battery test interval, in which case said battery passes a test.
Claim 3
Dependent Claim
60 words
A circuit as set forth in claim 1 wherein said means for supplying said load from said battery beginning at the start of and continuing during said battery test interval comprises a diode connected between said battery connection port and said output port, said diode being reversed biased when said main power source supplies its rated voltage to said load.
Claim 4
Dependent Claim
53 words
A circuit as set forth in claim 2 further comprising a second switch connected in series with said diode between said battery connection port and said output port and means for shutting off said second switch if the load voltage drops below another predetermined threshold voltage less than the first said threshold voltage.
Claim 5
Dependent Claim
31 words
A circuit as set forth in claim 1 further comprising means for turning-on said main switch if and when said output voltage drops below said threshold voltage during said test interval.
Claim 6
Dependent Claim
32 words
A circuit as set forth in claim 1 further comprising a charger powered by said main power source and connected to supply charging current to said battery via said battery connection port.
Claim 7
Dependent Claim
43 words
A circuit as set forth in claim 1 further comprising a diode connected in series with said main switch between said input and output ports and oriented to be forward biased when said main power source supplies its rated voltage to said load.
Claim 8
Dependent Claim
21 words
A circuit as set forth in claim 1 further comprising said battery, said battery being connected to said battery connection port.
Claim 9
Dependent Claim
25 words
A circuit as set forth in claim 1 wherein the determining means comprises a comparator coupled to compare the load voltage to said predetermined threshold.
Claim 10
Dependent Claim
15 words
A circuit as set forth in claim 1 wherein said load is a DC/DC converter.
Claim 11
Independent Claim
112 words
A method for testing a battery which backs-up and has lower rated voltage than a main power source, said method comprising the steps of: closing a switch and supplying drive current from the main power source to a load via the closed switch during normal operation; and opening said main switch at a start of a battery test interval, supplying drive current from the battery to said load beginning at the start of and continuing during said battery test interval and determining if said battery supplies said load with at least a predetermined threshold voltage for the duration of said battery test interval, in which case said battery passes a capacity test.
Claim 12
Independent Claim
112 words
A method for testing a battery which backs-up and has lower rated voltage than a main power source, said method comprising the steps of: closing a switch and supplying drive current from the main power source to a load via the closed switch during normal operation; and opening said main switch at a start of a battery test interval, supplying drive current from the battery to said load beginning at the start of and continuing during said battery test interval and determining if said battery supplies said load with at least a predetermined threshold voltage for the duration of said battery test interval, in which case said battery passes a capacity test.
Claim 13
Dependent Claim
46 words
A method as set forth in claim 10 wherein said battery is coupled to said load via a diode which is reversed biased when said main power source supplies its rated voltage to said load during said normal operation and forward biased during said test interval.
Claim 14
Dependent Claim
46 words
A method as set forth in claim 11 further comprising the step of opening a second switch connected in series with said diode between said battery and said load if the load voltage drops below another predetermined threshold voltage less than the first said threshold voltage.
Claim 15
Dependent Claim
32 words
A method as set forth in claim 10 further comprising the step of closing said main switch if and when the load voltage drops below said threshold voltage during said test interval.
Claim 16
Dependent Claim
21 words
A method as set forth in claim 10 further comprising the step of charging said battery from said main power source.
Claim 17
Dependent Claim
50 words
A method as set forth in claim 10 further comprising the step of connecting a diode in series with said main switch between said main power source and said load and orienting said diode to be forward biased when said main power source supplies its rated voltage to said load.
Claim 18
Dependent Claim
23 words
A method as set forth in claim 10 wherein the determining step is performed by comparing the load voltage to said predetermined threshold.
Claim 19
Dependent Claim
26 words
A method as set forth in claim 10 wherein said battery is interconnected to but does not supply current to said load during said normal operation.
Claim 20
Dependent Claim
15 words
A method as set forth in claim 10 wherein said load is a DC/DC converter.
References Cited (Backward Citations)
US4225792A
Cited
US4316133A
Cited
US4354118A
Cited
US4563628A
Cited
US4670702A
Cited
US4918368A
Cited
US5057697A
Cited
US5126585A
Cited
US5422559A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-06-18 | 1999-12-18 | 2000-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-06-18 | 2003-12-18 | 2004-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-06-18 | 2007-12-18 | 2008-06-18 | $7700.00 | Window Closed / Lapsed |