Power source switching apparatus and method thereof

• US 20070046264A1
• Filed: 08/24/2006
• Published: 03/01/2007
• Est. Priority Date: 08/24/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Jong-Sang
• Granted Patent: US 7,683,584 B2
• Time in Patent Office: Days
• US Class Current: 320/162
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A power source switching apparatus and method thereof are provided. The example power source switching apparatus may include a battery storing charges received from an external power source and outputting a voltage corresponding to the stored charges, a voltage adjuster outputting a first power source voltage having a voltage level, corresponding to the output voltage of the battery, during an external power source mode where the battery is being charged, the first power source voltage based at least in part on the external power source and the output voltage of the battery, a controller outputting a first control signal and a second control signal, the first control signal enabled if the battery is operating in the external power source mode and the second control signal is enabled if the battery is not operating in the external power source mode, a first switch outputting the first power source voltage if the first control signal is enabled and a second switch outputting the output voltage of the battery if the second control signal is enabled. In an example method, a first power source voltage may be provided if a battery is not being charged by an external power source voltage, the first power source voltage output by the battery. A second power source voltage may be provided if the battery is being charged by the external power source voltage, the second power source voltage corresponding to a voltage level of the first power source voltage and not provided from the battery.

Claims

1. A power source switching apparatus, comprising:

a battery storing charges received from an external power source and outputting a voltage corresponding to the stored charges;

a voltage adjuster outputting a first power source voltage having a voltage level, corresponding to the output voltage of the battery, during an external power source mode where the battery is being charged, the first power source voltage based at least in part on the external power source and the output voltage of the battery;

a controller outputting a first control signal and a second control signal, the first control signal enabled if the battery is operating in the external power source mode and the second control signal is enabled if the battery is not operating in the external power source mode;

a first switch outputting the first power source voltage if the first control signal is enabled; and

a second switch outputting the output voltage of the battery if the second control signal is enabled.

2. The power source switching apparatus of claim 1, further comprising:

a battery charger positioned between the external power source and the battery, the battery charger supplying charges received from the external power source to the battery.

3. The power source switching apparatus of claim 1, wherein the voltage adjuster includes:

an operational amplifier including a first input terminal receiving the output voltage of the battery; and

a MOS transistor including a source terminal connected to the external power source, a drain terminal connected to a second input terminal of the operational amplifier, and a gate terminal receiving an output voltage of the operational amplifier.

4. The power source switching apparatus of claim 3, wherein the voltage adjuster further includes:

a load including a first terminal connected to a node for connecting the second input terminal of the operational amplifier with the drain terminal of the MOS transistor, and a second terminal connected to a ground voltage.

5. The power source switching apparatus of claim 4, wherein the load includes:

a capacitor including a first terminal connected to a node for connecting the second input terminal of the operational amplifier with the drain terminal of the MOS transistor, and a second terminal connected to the ground voltage.

6. The power source switching apparatus of claim 5, wherein the load further includes:

a resistor connected to the capacitor in parallel.

7. The power source switching apparatus of claim 1, further comprising:

a direct current (DC)-DC converter generating a conversion voltage having a voltage level different from that of a switching voltage output by one of the first and second switches, the conversion voltage based on one or more of the first power source voltage output by the first switch and the output voltage output by the second switch.

8. The power source switching apparatus of claim 7, wherein a voltage level of the switching voltage is higher than that of the conversion voltage.

9. The power source switching apparatus of claim 1, further comprising:

a direct current (DC)-DC converter generating a conversion voltage having a voltage level different from that of a first switching voltage output by the second switch; and

a system load performing a function using the conversion voltage output from the DC-DC converter and a second switching voltage output from the first switch.

10. The power source switching apparatus of claim 9, wherein a voltage level of the first switching voltage is higher than that of the conversion voltage.

11. The power source switching apparatus of claim 1, wherein the controller further outputs a third control signal, the third control signal enabled if the battery is operating in an external power source mode, the voltage adjuster outputting the first power source voltage further based on the third control signal.

12. The power source switching apparatus of claim 11, wherein the voltage adjuster comprises:

an operational amplifier including a first input terminal receiving the output voltage of the battery; and

a MOS transistor including a source terminal connected to the external power source, a drain terminal connected to a second input terminal of the operational amplifier;

a third switch outputting one of the output voltage of the external power source and an output voltage of the operational amplifier to a gate terminal of the MOS transistor in response to the third control signal.

13. The power source switching apparatus of claim 12, wherein the voltage adjuster further includes:

a load including a first terminal connected to a node for connecting the second input terminal of the operational amplifier with the drain terminal of the MOS transistor, and a second terminal connected to a ground voltage.

14. The power source switching apparatus of claim 13, wherein the load further includes:

a capacitor including a first terminal connected to a node for connecting the second input terminal of the operational amplifier with the drain terminal of the MOS transistor, and a second terminal connected to the ground voltage.

15. The power source switching apparatus of claim 14, wherein the load further includes:

a resistor connected to the capacitor in parallel.

16. The power source switching apparatus of claim 1, wherein only one of the first control signal and the second control signal is enabled at any given time.

17. The power source switching apparatus of claim 11, wherein only one of the first control signal and the second control signal is enabled at any given time, and the third control signal is enabled at a given time period before the first control signal is enabled and is disabled at the concurrently with a disabling of the first control signal.

18. The power source switching apparatus of claim 17, wherein the given time period corresponds to a settling time until the first power source voltage has a voltage level substantially matching that of the battery.

19. The power source switching apparatus of claim 11, further comprising:

a direct current (DC)-DC converter generating a conversion voltage having a voltage level different from that of a switching voltage, the switching voltage output from a common node connected to each of the first switch and the second switch.

20. The power source switching apparatus of claim 19, wherein the voltage level of the switching voltage is higher than that of the conversion voltage.

21. The power source switching apparatus of claim 11, further comprising:

a direct current (DC)-DC converter generating a conversion voltage having a voltage level different from that of a first switching voltage output by the second switch; and

a system load performing a function using the conversion voltage output from the DC-DC converter and a second switching voltage output from the first switch.

22. The power source switching apparatus of claim 21, wherein the voltage level of the first switching voltage is higher than that of the conversion voltage.

23. A method of providing power, comprising:

providing a first power source voltage if a battery is not being charged by an external power source voltage, the first internal power source voltage output by the battery; and

providing a second power source voltage if the battery is being charged by the external power source voltage, the second power source voltage corresponding to a voltage level of the first power source voltage and not provided from the battery.

24. The method of claim 23, wherein the external power source voltage is higher than one or more of the first and second power source voltages.

25. The method of claim 23, wherein the second power source voltage is provided during a period of transition between a battery mode and an external power source mode.

26. A power source switching apparatus performing the method of claim 23.