Power source control circuit, power supply device, and control method for the same

Abstract

A control circuit for a power supply device, a power supply device, and the like are provided in which the power supply device has a plurality of DC/DC converters provided for generating voltage while the mutual relationship of potential between the voltage outputs is maintained. The control circuit 20 in the power supply device 10 which outputs different direct current voltages (VCC, VBGP, and VBGN) includes a voltage setting unit 22 for determining the setting level of a second direct current voltage VBGP which has a potential relationship with the setting level of the first direct current voltage VCC which is one of a plurality of the different direct current voltages.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuitry diagram of a power supply device according to a first embodiment of the present invention;

FIG. 2 is a circuitry diagram of a power supply device according to a second embodiment of the present invention;

FIG. 3 is a circuitry diagram of a power supply device according to a third embodiment of the present invention;

FIG. 4 is a block diagram showing the connection between a conventional power supply device and an external device;

FIG. 5 is a circuitry diagram of the conventional power supply device connected with a logic circuit in the external device; and

FIG. 6 is a circuitry diagram of the logic circuit.

Claims

1. A control circuit for a power supply device which outputs a plurality of direct current voltages different in a voltage level, comprising: a voltage setting unit for determining the setting level of a second direct current voltage having a potential relation to the setting level of a first direct current voltage which is one of the plurality of the direct current voltages.

2. The control circuit for a power supply device according to claim 1, wherein the voltage setting unit includes an adder for adding the setting level of the first direct current voltage with a difference between the setting level of the first direct current voltage and the setting level of the second direct current voltage thus to determine a setting level of the second direct current voltage.

3. The control circuit for a power supply device according to claim 2, comprising: a first direct current voltage data storage for storing data of the setting level of the first direct current voltage; anda voltage difference data storage for storing data of the difference between the setting levels.

4. The control circuit for a power supply device according to claim 2, comprising: a sum direct current voltage data storage for storing data of the setting level of the second direct current voltage determined by the adder.

5. The control circuit for a power supply device according to claim 1, wherein a plurality of the voltage setting units are provided and connected so that the setting level of the second direct current voltage determined by one of the plurality of the voltage setting units is delivered as the setting level of the first direct current voltage in another voltage setting unit which is different from the one of the plurality of the voltage setting units.

6. The control circuit for a power supply device according to claim 1, wherein the voltage setting unit includes a comparator for comparing between the setting level of the first direct current voltage and the setting level of another direct current voltage which is different from the first direct current voltage thus to determining a magnitude relationship, and a selector for, in response to the result of the magnitude relationship determined by the comparator, selecting as the setting level of the second direct current voltage either the setting level of the first direct current voltage or the setting level of the another direct current voltage whichever is greater in the voltage magnitude level.

7. The control circuit for a power supply device according to claim 6, comprising: a first direct current voltage data storage for storing data of the setting level of the first direct current voltage; anda direct current data storage for storing data of the setting level of the another direct current voltage.

8. The control circuit for a power supply device according to claim 6, comprising: a selected direct current voltage data storage for storing data of the setting level of the second direct current voltage selected by the selector.

9. A power supply device for outputting a plurality of direct current voltages which are different in the voltage level, comprising: a voltage setting unit for determining the setting level of a second direct current voltage which has a potential relation to the setting level of a first direct current voltage which is one of the plurality of the different direct current voltages.

10. The power supply device according to claim 9, wherein the voltage setting unit includes an adder for adding the setting level of the first direct current voltage with a difference between the setting level of the first direct current voltage and the setting level of the second direct current voltage thus to determine a setting level of the second direct current voltage.

11. The power supply device according to claim 10, comprising: a first direct current voltage data storage for storing data of the setting level of the first direct current voltage; anda voltage difference data storage for storing data of the difference between the setting levels.

12. The control circuit for a power supply device according to claim 10, further comprising: a sum direct current voltage data storage for storing data of the setting level of the second direct current voltage determined by the adder.

13. The power supply device according to claim 9, wherein a plurality of the voltage setting units are provided and connected so that the setting level of the second direct current voltage determined by one of the plurality of the voltage setting units is delivered as the setting level of the first direct current voltage in another voltage setting unit which is different from the one of the plurality of the voltage setting units.

14. The power supply device according to claim 9, wherein the voltage setting unit includes a comparator for comparing between the setting level of the first direct current voltage and the setting level of another direct current voltage which is different from the first direct current voltage thus to determining a magnitude relationship, and a selector for, in response to the result of the magnitude relationship determined by the comparator, selecting as the setting level of the second direct current voltage either the setting level of the first direct current voltage or the setting level of the another direct current voltage whichever is greater in the voltage magnitude level.

15. The power supply device according to claim 14, comprising: a first direct current voltage data storage for storing data of the setting level of the first direct current voltage; anda direct current data storage for storing data of the setting level of the another direct current voltage.

16. The power supply device according to claim 14, comprising: a selected direct current voltage data storage for storing data of the setting level of the second direct current voltage selected by the selector.

17. A control method of a power supply device which outputs a plurality of direct current voltages which are different in the voltage level, comprising the step of: determining the setting level of a second direct current voltage which has a potential relation to the setting level of a first direct current voltage which is one of the plurality of the plurality of the different direct current voltages.

18. The control method of a power supply device according to claim 17, comprising the step of: determining the setting level of the second direct current voltage includes adding the setting level of the first direct current voltage with a difference between the setting level of the first direct current and the setting level of the second direct current voltage.

19. The control method of a power supply device according to claim 17, comprising the step of: when a plurality of setting levels of the second direct current voltage are set, setting one of the plurality of the setting levels of the second direct current voltage as the setting level of the first direct current voltage having a potential relation to setting level of the another one of the second direct current voltages.

20. The control method of a power supply device according to claim 17, comprising the steps of: comparing between the setting level of the first direct current voltage and the setting level of another direct current voltage which is different from the first direct current voltage thus to determining a magnitude relationship; andin response to the result of the magnitude relationship, selecting as the setting level of the second direct current voltage either the setting level of the first direct current voltage or the setting level of the another direct current voltage whichever is greater in the voltage magnitude level.