Battery charger with segmented power path switch
AssigneeTexas Instruments Incorporated
InventorSanjay Gurlahosur
Life of this patent
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Abstract
A battery charger circuit having a regulator controller configured to control the switching transistors of a switching voltage regulator. A power path switch is disposed intermediate an output of the switching voltage regulator and a terminal of a battery to be charged, with the power path switch including at least two transistor segments having common respective drain electrodes, common respective source electrodes and separate respective gate electrodes. A power path switch controller operates to sequentially turn ON the at least two transistor segments of the power path switch, preferably in the order of a decreasing ON resistance.
Claims19
A charger circuit comprising:
- a switch;
- current detection circuitry coupled to the switch, the current detection circuitry configured to detect a short circuit condition based on a detected current of the switch exceeding a predefined threshold current;
- and
- a controller coupled to the switch and to the current detection circuitry, the controller configured to:
- in response to the current detection circuitry detecting the short circuit condition, increase a channel resistance of the switch from a first resistance to a second resistance;
- and
- in response to the current detection circuitry detecting the short circuit condition a time period after increasing the channel resistance of the switch from the first resistance to the second resistance, increase the channel resistance of the switch from the second resistance to a third resistance.
A device comprising:
- a voltage supply terminal;
- a battery;
- a switch coupled between the voltage supply terminal and the battery;
- current detection circuitry coupled to the switch, the current detection circuitry configured to detect a short circuit condition based on a detected current of the switch exceeding a predefined threshold current;
- and
- a controller coupled to the switch and to the current detection circuitry, the controller configured to:
- in response to the current detection circuitry detecting the short circuit condition, increase a channel resistance of the switch from a first resistance to a second resistance;
- and
- in response to the current detection circuitry detecting the short circuit condition a time period after increasing the channel resistance of the switch from the first resistance to the second resistance, increase the channel resistance of the switch from the second resistance to a third resistance.
A method comprising:
- detecting, by current detection circuitry, a short circuit condition based on a detected current of a switch exceeding a predefined threshold current;
- in response to the current detection circuitry detecting the short circuit condition, increasing, by a controller, a channel resistance of the switch from a first resistance to a second resistance;
- and
- in response to the current detection circuitry detecting the short circuit condition a time period after increasing the channel resistance of the switch from the first resistance to the second resistance, increasing, by the controller, the channel resistance of the switch from the second resistance to a third resistance.
Dependencies are inferred from the claim text.