Patent US5659238A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5659238A Expired / Lapsed US ⏱️ 0.0 years remaining

Computer battery pack charge current sensor with gain control

Assignee: HTC Corp
•
Filing: 1996-02-22
•
Granted: 1997-08-19
•
Expires: 2016-02-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A current switch is provided which selects and monitors charge and discharge states of a battery pack of a computer system. The current switch provides a current sense signal which is an indication of the current in the battery pack in order that a charge control circuit can monitor the charge state of the battery pack. The gain of the current sense signal is adjusted, depending on whether the battery pack is in a fast charging, trickle charging, or discharging state when the computer system is in a standby mode. Thus, the current switch provides a sufficient current sense signal for accurate current measurements while dissipating little power for the various battery pack charge states.

Inventors

  • 👤 Richard A. Faulk
  • 👤 John C. Schluter

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 10:02
CPC Classifications
H; H01; H01M; H01M10/00; H01M10/42; H01M10/44; H02; H02J; H02J7/00; H02J7/865; H02J7/60; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S320/00; Y10S320/18; Y10S320/21

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 280 words
A current sensor for monitoring discharge currents from a battery while the battery is connected to a system capable of discharging the battery in at least first and second discharge states, the system providing an indication of the first discharge state and an indication of the second discharge state, the current sensor comprising: a first sense resistor for coupling in series with the battery during the first discharge state and having a first terminal for providing a first current signal indicating the current in the battery during the first discharge state; a second sense resistor for coupling in series with the battery during the second discharge state and having a first terminal for providing a second current signal indicating the current in the battery during the second discharge state; a third resistor having a first terminal for receiving the second current signal and a second terminal for providing a sense signal indicative of the current in the battery during the second discharge state; a first switch having a series switched path activated by a control terminal for coupling said first resistor and the battery in series when the system indicates the first discharge state and for decoupling said first resistor and the battery when the system indicates the second discharge state; and a second switch having a series switched path activated by a control terminal, the series switched path of said second switch having a first terminal coupled to the first terminal of said first sense resistor for receiving the first current signal and having a second terminal coupled to the second terminal of said third resistor for providing the sense signal when the system indicates the first discharge state.
Claim 2
Dependent Claim 280 words
A current sensor for monitoring discharge currents from a battery while the battery is connected to a system capable of discharging the battery in at least first and second discharge states, the system providing an indication of the first discharge state and an indication of the second discharge state, the current sensor comprising: a first sense resistor for coupling in series with the battery during the first discharge state and having a first terminal for providing a first current signal indicating the current in the battery during the first discharge state; a second sense resistor for coupling in series with the battery during the second discharge state and having a first terminal for providing a second current signal indicating the current in the battery during the second discharge state; a third resistor having a first terminal for receiving the second current signal and a second terminal for providing a sense signal indicative of the current in the battery during the second discharge state; a first switch having a series switched path activated by a control terminal for coupling said first resistor and the battery in series when the system indicates the first discharge state and for decoupling said first resistor and the battery when the system indicates the second discharge state; and a second switch having a series switched path activated by a control terminal, the series switched path of said second switch having a first terminal coupled to the first terminal of said first sense resistor for receiving the first current signal and having a second terminal coupled to the second terminal of said third resistor for providing the sense signal when the system indicates the first discharge state.
Claim 3
Dependent Claim 23 words
The current sensor of claim 1, wherein the system is a computer system that is fully powered up during the first discharge state.
Claim 4
Dependent Claim 24 words
The current sensor of claim 1, wherein the system is a computer system that is in a standby mode during the second discharge state.
Claim 5
Dependent Claim 35 words
The current sensor of claim 1, further comprising: a fourth resistor coupled in series with said second sense resistor and the battery, said fourth resistor provided to select a trickle charge current for the battery.
Claim 6
Dependent Claim 35 words
The current sensor of claim 4, further comprising: a diode coupled in parallel with said fourth resistor, said diode provided to bypass the current limiting provided by said fourth resistor during the second discharge state.
Claim 7
Dependent Claim 13 words
The current sensor of claim 5 wherein said diode is a Schottky diode.
Claim 8
Dependent Claim 22 words
The current sensor of claim 1, wherein the resistance of said first resistor is smaller than the resistance of said second resistor.
Claim 9
Dependent Claim 14 words
The current sensor of claim 1, wherein said first switch is a metal-oxide-semiconductor field-effect-transistor.
Claim 10
Dependent Claim 14 words
The current sensor of claim 1, wherein said second switch is a metal-oxide-semiconductor field-effect-transistor.
Claim 11
Dependent Claim 280 words
A current sensor for monitoring charge currents in a battery while the battery is connected to a system capable of charging the battery in at least first and second charge states, the system providing an indication of the first charge state and an indication of the second charge state, the current sensor comprising: a first sense resistor for coupling in series with the battery during the first charge state and having a first terminal for providing a first current signal indicating the current in the battery during the first charge state; a second sense resistor for coupling in series with the battery during the second charge state and having a first terminal for providing a second current signal indicating the current in the battery during the second charge state; a third resistor having a first terminal for receiving the second current signal and having a second terminal for providing a sense signal indicative of the current in the battery during the second charge state; a first switch having a series switched path activated by a control terminal for coupling said first resistor and the battery in series when the system indicates the first charge state and for decoupling said first resistor and the battery when the system indicates the second charge state; and a second switch having a series switched path activated by a control terminal, the series switched path of said second switch having a first terminal coupled to the first terminal of said first resistor for receiving the first current signal and having a second terminal coupled to the second terminal of said third resistor for providing the sense signal when the system indicates the first charge state.
Claim 12
Dependent Claim 280 words
A current sensor for monitoring charge currents in a battery while the battery is connected to a system capable of charging the battery in at least first and second charge states, the system providing an indication of the first charge state and an indication of the second charge state, the current sensor comprising: a first sense resistor for coupling in series with the battery during the first charge state and having a first terminal for providing a first current signal indicating the current in the battery during the first charge state; a second sense resistor for coupling in series with the battery during the second charge state and having a first terminal for providing a second current signal indicating the current in the battery during the second charge state; a third resistor having a first terminal for receiving the second current signal and having a second terminal for providing a sense signal indicative of the current in the battery during the second charge state; a first switch having a series switched path activated by a control terminal for coupling said first resistor and the battery in series when the system indicates the first charge state and for decoupling said first resistor and the battery when the system indicates the second charge state; and a second switch having a series switched path activated by a control terminal, the series switched path of said second switch having a first terminal coupled to the first terminal of said first resistor for receiving the first current signal and having a second terminal coupled to the second terminal of said third resistor for providing the sense signal when the system indicates the first charge state.
Claim 13
Dependent Claim 20 words
The current sensor of claim 10, wherein the first charge state indicated by the system is a fast charge state.
Claim 14
Dependent Claim 20 words
The current sensor of claim 10, wherein the second charge state indicated by the system is a trickle charge state.
Claim 15
Dependent Claim 38 words
The current sensor of claim 10, further comprising: a fourth resistor coupled in series with said second sense resistor and the battery, said fourth resistor provided to select the current in the battery during the second charge state.
Claim 16
Dependent Claim 22 words
The current sensor of claim 10, wherein the resistance of said first resistor is smaller than the resistance of said second resistor.
Claim 17
Dependent Claim 14 words
The current sensor of claim 10, wherein said first switch is a metal-oxide-semiconductor field-effect-transistor.
Claim 18
Dependent Claim 14 words
The current sensor of claim 10, wherein said second switch is a metal-oxide-semiconductor field-effect-transistor.

References Cited (Backward Citations)

US4609860A Cited
US5315228A Cited
US5371456A Cited
US5514946A Cited
US5554921A Cited
US5576609A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-08-18 2001-02-17 2001-08-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-08-18 2005-02-17 2005-08-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-08-18 2009-02-17 2009-08-19 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag