Pulse width modulation controller of DC-DC converter

• US 9,263,947 B2
• Filed: 12/02/2013
• Issued: 02/16/2016
• Est. Priority Date: 08/05/2009
• Status: Active Grant

• Current Assignee: uPI Semiconductor Corporation
• Original Assignee: uPI Semiconductor Corporation
• Inventors: Chien, Min-Chu, Huang, Yung-Peng
• Primary Examiner(s): Pham, Emily P
• Application Number:
  US14/093,735
• Publication Number:
  US 20140084891A1
• Time in Patent Office: 806 Days
• US Class Current: 1/1
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A DC-DC converter including a Pulse Width Modulation (PWM) controller for converting an input voltage into an output voltage is provided. The PWM controller includes a first comparator, receiving a compensated error signal and a ramp signal, wherein when the compensated error signal exceeds the ramp signal, the first comparator generates a trigger signal. The PWM controller further includes a PWM generator coupled to the first comparator, providing a timing signal according to the trigger signal to control the operation of the DC-DC converter.

Claims

1. A Pulse Width Modulation (PWM) controller of a DC-DC converter, comprising:

a first comparator, receiving a compensated error signal and a ramp signal, wherein when the compensated error signal exceeds the ramp signal, the first comparator generates a trigger signal;

a PWM generator coupled to the first comparator, providing a timing signal according to the trigger signal to control the operation of the DC-DC converter; and

a compensation unit, compensating an error signal and causing an included angle between the compensated error signal and the ramp signal to increase.

2. The PWM controller as claimed in claim 1, further comprising an error signal generator and a compensation unit, wherein the compensation unit is coupled between an output of the error signal generator and a ground, and the compensated error signal is provided by the compensation unit.

3. The PWM controller as claimed in claim 1, wherein the compensated error signal is provided by an error signal generator and a compensation unit coupled to an output of the error signal generator.

4. The PWM controller as claimed in claim 3, wherein the error signal generator receives a reference voltage and a feedback voltage corresponding to an output voltage of the DC-DC converter to provide an error signal, and the compensation unit provides the compensated error signal according to the error signal.

5. The PWM controller of a DC-DC converter as claimed in claim 1, further comprising:

a sense unit, generating a sense current corresponding to an output current of the DC-DC converter;

wherein the compensation unit is coupled to the sense unit, and provides the compensated error signal according to the error signal and the sense current.

6. The PWM controller of a DC-DC converter as claimed in claim 5, wherein the compensation unit further comprises a first resistor and a first capacitor, wherein the first capacitor is coupled to the first resistor in series.

7. The PWM controller of a DC-DC converter as claimed in claim 6, wherein the compensation unit further comprises:

a second resistor coupled between the sense unit and a ramp generator,

wherein a voltage across the second resistor corresponds to the sense current, and the compensated error signal is generated according to the sense current, the ramp signal and the voltage across the second resistor.

8. A Pulse Width Modulation (PWM) controller of a DC-DC converter, comprising:

a sense unit, generating a sensing signal corresponding to an output current of the DC-DC converter;

a compensation unit coupled to the sense unit, generating a compensated signal according to the sensing signal and a ramp signal;

a first comparator, receiving the compensated signal and an error signal, wherein when the error signal exceeds the compensated signal, the first comparator generates a trigger signal;

a PWM generator coupled to the first comparator, providing a timing signal according to the trigger signal; and

a ramp generator coupled to the PWM generator, generating the ramp signal according to the timing signal.

9. A Pulse Width Modulation (PWM) controller of a DC-DC converter, comprising:

a sense unit, generating a sensing signal corresponding to an output current of the DC-DC converter;

a compensation unit coupled to the sense unit, compensating one of an error signal and a ramp signal to generate a compensated signal according to the sensing signal;

a first comparator coupled to the compensation unit, generating a trigger signal according to the compensated signal and another of the error signal and the ramp signal; and

a PWM generator coupled to the first comparator, providing a timing signal according to the trigger signal,

wherein the compensation unit comprises;

a resistor coupled between the sense unit and the first comparator; and

a current source coupled between the resistor and a ground, sinking a current corresponding to the sensing signal from the resistor to the ground.

10. The PWM controller of a DC-DC converter as claimed in claim 9, wherein the PWM controller is coupled to a first switch and a second switch, a node is between the first switch and the second switch, and an output inductor is coupled to the node, the timing signal is used for controlling the operation of the first switch and the second switch.

11. The PWM controller of a DC-DC converter as claimed in claim 10, wherein the sense unit is coupled to the node to generate the sensing signal.

12. The PWM controller of a DC-DC converter as claimed in claim 9, wherein the sensing signal is an inductor current.

13. The PWM controller of a DC-DC converter as claimed in claim 9, wherein when the error signal is compensated by the compensation unit and the compensated signal exceeds the ramp signal, the first comparator generates the trigger signal.

14. The PWM controller of a DC-DC converter as claimed in claim 9, wherein when the ramp signal is compensated by the compensation unit and the error signal exceeds the compensated signal, the first comparator generates the trigger signal.