DC-DC CONVERTER AND INFORMATION PROCESSING DEVICE

• US 20130049712A1
• Filed: 06/08/2012
• Published: 02/28/2013
• Est. Priority Date: 08/23/2011
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: UENO, Takeshi
• Granted Patent: US 9,065,338 B2
• Time in Patent Office: Days
• US Class Current: 323/234
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel

Abstract

There is provided a DC-DC converter which converts an input voltage into an output voltage for supply to a load, in which an input terminal receives the input voltage, an output terminal outputs the output voltage, power stages each includes: a high side switch, a low side switch and an inductor, the control unit executes a first mode and a second mode wherein the first mode controls the high side switch and the low side switch in each of the power stages so that a ratio of an output current in each of the power stages to a load current flowing through the load becomes a set value and the second mode controls the high side switch and the low side switch in each of the power stages so that duty ratios of the high side switch and the low side switch are equalized among the power stages.

Claims

1. A DC-DC converter which converts an input voltage into an output voltage having a value different that of the input voltage and supplies the output voltage to a load, comprising:

an input terminal to receive the input voltage;

an output terminal to output the output voltage;

a plurality of power stages each including;

a high side switch one end of which is connected to the input terminal and;

a low side switch one end of which is connected to an ground terminal and the other end of which is connected to the other end of the high side switch; and

an inductor one end of which is connected to the other end of the high side switch and the other end of which is connected to the output terminal; and

a control unit configured to execute;

a first mode of controlling the high side switch and the low side switch in each of the power stages so that a ratio of an output current of each of the power stages to a load current flowing through the load becomes a set value; and

a second mode of controlling the high side switch and the low side switch in each of the power stages so that duty ratios of the high side switch and the low side switch are equalized among the power stages.

2. The converter according to claim 1, wherein the control unit executes the first mode when the load current is larger than a threshold value, and executes the second mode when the load current is equal to or smaller than the threshold value.

3. The converter according to claim 1, further comprising a terminal to receive from outside a signal indicating whether the load current is equal to or larger than the threshold value,

wherein the control unit determines based on the signal received by the terminal whether the load current is larger than the threshold value.

4. The converter according to claim 2, wherein the control unit performs control in the first mode so that the power stages each supplies the output current to the load at same ratio to the load current.

5. The converter according to claim 2, wherein the control unit performs control in the first mode so that each power stage supplies the output current to the load at a different ratio to the load current.

6. The converter according to claim 1, wherein the control unit

includes a plurality of variable gain amplifiers each amplifying a signal corresponding to a difference between an average of output currents of the power stages and the output current of each of the power stages,

controls the high side switch and the low side switch in each of the power stages based on an addition signal obtained by adding an amplified signal by each of the variable gain amplifier to a difference between the output voltage and a target voltage, and

controls a gain of each of the variable gain amplifiers on the basis of the load current.

7. The converter according to claim 1, wherein the control unit executes the first mode when at least one of output currents from the power stages is equal to or larger than a threshold value, and executes the second mode when all the currents from the power stages are smaller than the threshold value.

8. An information processing device comprising:

a DC-DC converter according to claim 1; and

an electronic equipment being the load.