Power supply apparatus and method of controlling power supply circuit

• US 6,177,786 B1
• Filed: 03/12/1999
• Issued: 01/23/2001
• Est. Priority Date: 03/31/1998
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Shimamori, Hiroshi
• Primary Examiner(s): NGUYEN, MATTHEW VAN
• Application Number:
  US09/266,874
• Time in Patent Office: 683 Days
• Field of Search: 363/20, 363/21, 363/97, 363/131, 323/222, 323/282, 323/283, 323/285, 323/286
• US Class Current: 323/283
• CPC Class Codes: H02M 3/157 with digital control

Abstract

The DC output of a power conversion unit is controlled based on a pulse signal generated by a PWM unit. An operations unit detects an output current Iout, and determines the operation mode of a load based on the detected current value. When the output current Iout is weak, a value smaller than usual is written to a cycle register. The PWM unit generates a pulse signal according to the data stored in the cycle register and an on-time register.

Claims

1. A power supply apparatus comprising:

a power supply circuit for generating DC output based on a pulse signal;

conversion means for converting a parameter relating to output of said power supply circuit into digital data;

amplification means for amplifying a difference between the digital data obtained by said conversion means and a reference value;

adjustment means for adjusting a characteristic of said amplification means based on an input voltage of said power supply circuit; and

generation means for generating a pulse signal to be provided for said power supply circuit based on the output of said amplification means.

5. The power supply apparatus according to claim 1, wherein

said amplification means is a digital filter.

2. A power supply apparatus comprising:

a power supply circuit for generating DC output based on a pulse signal;

conversion means for converting a parameter relating to output of said power supply circuit into digital data;

amplification means for amplifying a difference between the digital data obtained by said conversion means and a reference value;

adjustment means for adjusting a characteristic of said amplification means based on an output current of said power supply circuit; and

generation means for generating a pulse signal to be provided for said power supply circuit based on the output of said amplification means.

3. A power supply apparatus comprising:

a power supply circuit for generating DC output based on a pulse signal;

conversion means for converting a parameter relating to output of said power supply circuit into digital data;

amplification means for amplifying a difference between the digital data obtained by said conversion means and a reference value;

adjustment means for adjusting a characteristic of said amplification means based on a temperature around said power supply circuit; and

generation means for generating a pulse signal to be provided for said power supply circuit based on the output of said amplification means.

4. A power supply apparatus comprising:

a power supply circuit for setting a plurality of values for an output voltage to be maintained, and generating DC output based on a pulse signal;

conversion means for converting the output voltage of said power supply circuit into digital data;

amplification means for amplifying a difference between the digital data obtained by said conversion means and a reference value;

adjustment means for adjusting a characteristic of said amplification means based on an output voltage of said power supply circuit; and

generation means for generating a pulse signal to be provided for said power supply circuit based on the output of said amplification means.

6. A power supply apparatus comprising:

a power supply circuit for generating DC output based on a pulse signal;

conversion means for converting a parameter relating to output of said power supply circuit into digital data;

amplification means for amplifying a difference between the digital data obtained by said conversion means and a reference value;

adjustment means for adjusting a characteristic of said amplification means based on an input voltage of said power supply circuit, an output current of said power supply circuit, and a temperature around said power supply circuit; and

generation means for generating a pulse signal to be provided for said power supply circuit based on the output of said amplification means.

7. A method of controlling an output voltage of a power supply circuit for generating DC output based on a pulse signal, comprising the steps of:

converting a parameter relating to output of the power supply circuit into digital data;

amplifying a difference between the digital data and a reference value using a digital filter through which a characteristic is adjusted based on an input voltage of the power supply circuit; and

generating a pulse signal to be provided for the power supply circuit based on output of the digital filter.

8. A method of controlling an output voltage of a power supply circuit for generating DC output based on a pulse signal, comprising the steps of:

converting a parameter relating to output of the power supply circuit into digital data;

amplifying a difference between the digital data and a reference value using a digital filter through which a characteristic is adjusted based on an output current of the power supply circuit; and

generating a pulse signal to be provided for the power supply circuit based on output of the digital filter.

9. A method of controlling an output voltage of a power supply circuit for generating DC output based on a pulse signal, comprising the steps of:

converting a parameter relating to output of the power supply circuit into digital data;

amplifying a difference between the digital data and a reference value using a digital filter through which a characteristic is adjusted based on a temperature around the power supply circuit; and

generating a pulse signal to be provided for the power supply circuit based on output of the digital filter.

10. A method of controlling an output voltage of a power supply circuit for setting a plurality of values for an output voltage to be maintained and generating DC output based on a pulse signal, comprising:

converting a parameter relating to output of the power supply circuit into digital data;

amplifying a difference between the digital data and a reference value using a digital filter through which a characteristic is adjusted based on an output voltage of the power supply circuit; and

generating a pulse signal to be provided for the power supply circuit based on output of the digital filter.

11. A power supply apparatus comprising:

a power supply circuit for generating DC output based on a pulse signal;

detection means for detecting an operating state of a load connected to the power supply circuit;

sampling means for sampling a parameter used for control of the output of the power supply circuit;

conversion means for converting the parameter sampled by said sampling means into digital data;

amplification means for amplifying a difference between the digital data obtained by said conversion means and a reference value;

adjustment means for adjusting a characteristic of said amplification means according to a detection result from said detection means; and

generation means for generating a pulse signal to be provided for the power supply circuit based on the output of said amplification means.

12. A power supply apparatus comprising:

a power supply circuit for generating DC output based on a pulse signal;

detection means for detecting an operating state of a load connected to the power supply circuit;

sampling means for sampling a parameter used for control of the output of the power supply circuit;

adjustment means for adjusting a sampling cycle performed by said sampling means according to a detection result from said detection means;

conversion means for converting the parameter sampled by said sampling means into digital data; and

generation means for generating a pulse signal to be provided for the power supply circuit based on the digital data obtained from said conversion means.

13. The power supply apparatus according to claim 12, wherein:

said generation means has a configuration with which digital data can be obtained from said conversion means in a polling process; and

said adjustment means adjusts a cycle of the polling process according to the detection result from said detection means.

14. A power supply apparatus having a power supply circuit which has a smoothing coil and whose DC output is controlled based on a pulse signal;

comprising;

conversion means for converting a parameter relating to the output of the power supply circuit into digital data;

adjustment means for adjusting a cycle of the pulse signal based on an output current or a coil current of the power supply circuit; and

generation means for generating a pulse signal to be provided for the power supply circuit based on the digital data obtained by said conversion means and the pulse cycle adjusted by said adjustment means.

15. The power supply apparatus according to claim 14, wherein

inductance of said smoothing coil can be changed according to an electric current.

16. A power supply apparatus having a power supply circuit which has a smoothing coil and whose DC output is controlled based on a pulse signal;

comprising;

detection means for detecting an operating state of a load connected to the power supply circuit;

adjustment means for adjusting a cycle of the pulse signal based on a detection result from said detection means;

conversion means for converting a parameter relating to the output of the power supply circuit into digital data;

generation means for generating a pulse signal to be provided for the power supply circuit based on the digital data obtained by said conversion means and the pulse cycle adjusted by said adjustment means, wherein

inductance of said smoothing coil can be changed according to an electric current.

17. A power supply apparatus having a power supply circuit which has a set of switching elements and whose DC output is controlled based on a pulse signal provided for the set of switching elements, comprising:

conversion means for converting a parameter relating to the output of the power supply circuit into digital data;

generation means for generating a pulse signal to be provided for the set of switching elements based on the digital data obtained from said conversion means; and

adjustment means for adjusting a dead-off time of the pulse signal based on at least one of an input voltage of the power supply circuit, an output current of the power supply circuit, and a temperature around the power supply circuit.

18. A method of controlling an output voltage of a power supply circuit for generating DC output based on a pulse signal, comprising the steps of:

detecting a state of a load connected to the power supply circuit;

sampling a parameter for use in controlling the output of the power supply circuit;

adjusting a cycle of the sampling based on the state of the load;

converting the sampled parameter into digital data;

amplifying a difference between the digital data and a reference value using a digital filter;

adjusting a characteristic of the digital filter based on a state of the load; and

generating a pulse signal to be provided for the power supply circuit based on the amplified data.

19. A method of controlling an output voltage of a power supply circuit which has a smoothing coil and whose DC output is controlled based on a pulse signal, comprising the steps of:

converting a parameter relating to output of the power supply circuit into digital data;

determining a cycle of the pulse signal based on an output current or a coil current of the power supply circuit; and

generating a pulse signal to be provided for the power supply circuit based on the digital data and the determined cycle of the pulse signal.