Method for limiting battery discharging current in battery charger and discharger circuit
First Claim
1. A power supply system, comprising:
- a single reconfigurable buck/boost system couplable to an adapter for receiving power therefrom and couplable to a rechargeable battery which is connectable to deliver a supply current to a load, the charger system limiting current drawn from the adapter and charging the battery in the buck mode; and
the single reconfigurable buck/boost system operating in a boost mode for operating the load at least in part from the battery and to regulate a discharge current from said rechargeable battery when said rechargeable battery is supplying power to said load,wherein the reconfigurable buck/boost system comprises a first switch couplable to an output bus of the adapter in series with a second switch coupled to a reference voltage, a common node between the first and second switches being coupled to one terminal of the inductor, the other terminal of which is couplable to the battery, the reconfigurable buck/boost system operating the first and second switches in buck mode in which current flows into the battery in a first direction and operates the first and second switches in a boost mode in which current flows in a second direction from the battery to the output bus of the adapter.
1 Assignment
0 Petitions
Accused Products
Abstract
A power supply system includes a rechargeable battery to deliver a supply current to a load and a circuit to limit a discharge current when the rechargeable battery is supplying power to the load. The power supply system may further include an integrator for integrating a discharge voltage representing the discharge current that exceeds a predetermined limit, a pulse-width-modulation (PWM) circuit for producing a control signal having a PWM duty cycle representing the discharge voltage, and a driver circuit for delivering the supply current to said load according to said control signal. In one embodiment, a digital register is used to set the battery discharging current limit, in another embodiment an analog circuit is used to set the battery discharging current limit, and in yet another embodiment or a combination of the digital register and analog circuit is used to set the battery discharging current limit.
24 Citations
19 Claims
-
1. A power supply system, comprising:
-
a single reconfigurable buck/boost system couplable to an adapter for receiving power therefrom and couplable to a rechargeable battery which is connectable to deliver a supply current to a load, the charger system limiting current drawn from the adapter and charging the battery in the buck mode; and the single reconfigurable buck/boost system operating in a boost mode for operating the load at least in part from the battery and to regulate a discharge current from said rechargeable battery when said rechargeable battery is supplying power to said load, wherein the reconfigurable buck/boost system comprises a first switch couplable to an output bus of the adapter in series with a second switch coupled to a reference voltage, a common node between the first and second switches being coupled to one terminal of the inductor, the other terminal of which is couplable to the battery, the reconfigurable buck/boost system operating the first and second switches in buck mode in which current flows into the battery in a first direction and operates the first and second switches in a boost mode in which current flows in a second direction from the battery to the output bus of the adapter. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A power supply system, comprising:
-
a rechargeable battery connectable to deliver a supply current to a load; a circuit to limit a discharge current from said rechargeable battery when said rechargeable battery is supplying power to said load, wherein said circuit to limit a discharge current comprises; a circuit to sense a discharge current from said rechargeable battery to produce a discharge voltage representing said discharge current; a digital register for containing a digital value representing a desired discharge current limit; a d/a converter to convert said digital value to a first reference voltage; a reference voltage source to produce a second reference voltage; a first operational amplifier to amplify said first reference voltage with said discharge voltage to produce a first output that follows said discharge voltage when said discharge voltage is larger than said first reference voltage; a second operational amplifier to amplify said second reference voltage with said discharge voltage produce a second output that follows said discharge voltage when said discharge voltage is larger than said second reference voltage; and a circuit to produce a combined voltage from said first and second outputs. - View Dependent Claims (10, 11, 12)
-
-
13. A method for operating a power supply system, comprising:
-
receiving power from an adapter output bus in a single reconfigurable buck/boost system for charging a rechargeable battery in a buck mode wherein first and second series connected switches coupled between the adapter output bus and a reference voltage operated to control current flow in a first direction into the battery, the battery being connectable to deliver a supply current to a load; limiting current drawn from the adapter by the buck/boost system; operating the single reconfigurable buck/boost system in a boost mode wherein the first and second switches are operated to cause current to flow in a second direction from the battery to the adapter output bus to operate the load at least in part from the battery; and regulating a discharge current from said rechargeable battery when said rechargeable battery is supplying power to said load. - View Dependent Claims (14, 15, 16, 17, 18, 19)
-
Specification