Power factor correction control circuit and driving method thereof

Patent metadata

Field	Value
Publication number	US-10231302-B2
Application number	US-201514819616-A
Country	US
Kind code	B2
Filing date	Aug 6, 2015
Priority date	Sep 15, 2014
Publication date	Mar 12, 2019
Grant date	Mar 12, 2019

Abstract

A circuit for adjusting a frequency of an AC direct lighting apparatus is provided. The circuit may include a reference voltage generation unit configured to receive a dimming voltage having a first frequency and a first voltage range, and generate a reference voltage having a second voltage range, a sensing section determining unit configured to generate first and second section reference voltages based on the reference voltage, and determine a driving current sensing section using the first and second section reference voltages, and a driving signal generation unit configured to generate a switching device driving signal having a second frequency through the determined driving current sensing section.

First claim

What is claimed is:

1. A circuit for adjusting a frequency of an AC (Alternating Current) direct lighting apparatus, comprising:
a reference voltage generation unit that receives a dimming voltage having a first frequency and a first voltage range, and generates a reference voltage having a second voltage range;
a sensing section determining unit that generates first and second section reference voltages based on the reference voltage, and determines a driving current sensing section based on the first and second section reference voltages; and
a driving signal generation unit that generates a switching device driving signal having a second frequency during the driving current sensing section, wherein the second frequency is determined based on a duration of the driving current sensing section, and wherein the second frequency has a fixed switching frequency regardless of a change of the reference voltage.

2. The circuit of claim 1 , wherein the reference voltage generation unit converts the dimming voltage into a current and mirrors the converted current to generate a first mirroring current.

3. The circuit of claim 2 , wherein the reference voltage generation unit converts the first mirroring current into a voltage through a digital-analog converter and generates the reference voltage through an OP (Operational) amplifier.

4. A circuit for adjusting a frequency of an AC (Alternating Current) direct lighting apparatus, comprising:
a reference voltage generation unit that receives a dimming voltage having a first frequency and a first voltage range, and generates a reference voltage having a second voltage range;
a sensing section determining unit that generates first and second section reference voltages based on the reference voltage, and determines a driving current sensing section based on the first and second section reference voltages; and
a driving signal generation unit that generates a switching device driving signal having a second frequency during the driving current sensing section,
wherein the sensing section determining unit comprises:
a section reference voltage generation module that distributes the reference voltage by voltage drop across a series of resistors, and generates the first and second section reference voltages based on a resistance ratio between the series of resistors; and
a frequency determining module that mirrors a current having the same magnitude as that of the current flowing to the section reference voltage generation module to induce a second mirroring current, and charges or discharges a first capacitor having a first capacitance through the second mirroring current to determine a second frequency.

5. The circuit of claim 4 , wherein the frequency determining module generates a predetermined period based on a capacitance ratio of the first capacitor and a second capacitor through a procedure to charge or discharge the second capacitor having a second capacitance.

6. The circuit of claim 5 , wherein the frequency determining module charges the first capacitor during the predetermined period and charges the second capacitor during the driving current sensing section.

7. The circuit of claim 1 , wherein the driving signal generation unit comprises:
an enable signal generation module that generates and transmits first to fourth enable signals to control first and second switching devices of the sensing section determining unit in order to charge first and second capacitors and to control third and fourth switching devices of the sensing section determining unit in order to discharge the first and second capacitors; and
a driving signal generation module that generates the switching device driving signal having a second frequency based on voltages applied across the first and second capacitors and the driving current sensing section.

8. The circuit of claim 7 , wherein the driving signal generation unit senses a driving current on a range of the driving current sensing section and charges the second capacitor to control a voltage spike occurrence.

9. A method for adjusting a frequency of an AC (Alternating Current) direct lighting apparatus, comprising:
receiving a dimming voltage having a first frequency and a first voltage range;
generating a reference voltage having a second voltage range based on the dimming voltage;
generating first and second section reference voltages based on the reference voltage;
determining a driving current sensing section based on the first and second section reference voltages; and
generating a switching device driving signal having a second frequency during the driving current sensing section, wherein the second frequency is determined based on a duration of the driving current sensing section, and wherein the generating the switching device driving signal comprises:
generating and transmitting first to fourth enable signals to control first and second switching devices in order to charge first and second capacitors and to control third and fourth switching devices in order to discharge the first and second capacitors; and
generating the driving signal having the second frequency based on voltages applied across the first and second capacitors and the driving current sensing section.

10. The method of claim 9 , wherein the generating the first and second section reference voltages comprises distributing the reference voltage into a plurality of resistance elements through a reference current to generate first and second section reference voltages.

11. A method for adjusting a frequency of an AC (Alternating Current) direct lighting apparatus, comprising:
receiving a dimming voltage having a first frequency and a first voltage range;
generating a reference voltage having a second voltage rang based on the dimming voltage;
generating first and second section reference voltages based on the reference voltage, wherein the generating the first and second section reference voltages comprises distributing the reference voltage into a plurality of resistance elements through a reference current to generate first and second section reference voltages;
determining a driving current sensing section based on the first and second section reference voltages, wherein the determining the driving current sensing section comprises:
mirroring the reference current to induce a second mirroring current; and
charging or discharging a first capacitor having a first capacitance through the second mirroring current to determine the second frequency; and

generating a switching device driving signal having a second frequency during the driving current sensing section, wherein the second frequency is determined based on a duration of the driving current sensing section.

12. The circuit of claim 4 , rein the second frequency is determined based on a duration of the driving current sensing section.

13. The method of claim 11 , wherein the generating the switching device driving signal comprises:
generating and transmitting first to fourth enable signals to control first and second switching devices in order to charge the first capacitor and a second capacitor and to control third and fourth switching devices in order to discharge the first and second capacitors; and
generating the driving signal having the second frequency based on voltages applied across the first and second capacitors and the driving current sensing section.

Assignees

• Magnachip Semiconductor Ltd

Inventors

• Lim Gyu Ho
• Kang Tae Kyoung
• Cui zhi yuan

Classifications

• H05B45/10 Primary

  Controlling the intensity of the light · CPC title

• H05B33/0845 Primary

  Electricity · mapped topic

• H05B33/0815

  Electricity · mapped topic

• H05B45/397

  Current mirror circuits · CPC title

• H05B47/10

  Controlling the light source · CPC title