CN109286321B - Switching power supply circuit - Google Patents
Switching power supply circuit Download PDFInfo
- Publication number
- CN109286321B CN109286321B CN201810910213.6A CN201810910213A CN109286321B CN 109286321 B CN109286321 B CN 109286321B CN 201810910213 A CN201810910213 A CN 201810910213A CN 109286321 B CN109286321 B CN 109286321B
- Authority
- CN
- China
- Prior art keywords
- transformer
- power supply
- supply circuit
- control chip
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
- H02M3/33592—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a switching power supply circuit, including first transformer and second transformer, be located the first pulse width modulation control chip of the secondary side of first transformer, be located the second pulse width modulation control chip of the primary side of first transformer, and connect the first power switch between the primary winding of first transformer and reference ground, wherein: the electric energy provided by the alternating current power supply is transmitted from the circuit input end of the switching power supply circuit to the circuit output end through the first transformer; the first PWM control chip transmits a PWM control signal for controlling the on and off of the first power switch to the second PWM control chip through a second transformer; the second PWM control chip controls the first power switch to be switched on and off based on the PWM control signal from the first PWM control chip.
Description
Technical Field
The invention relates to the field of circuits, in particular to a switching power supply circuit.
Background
In recent years, as screens of portable devices such as smartphones, tablet computers, and notebook computers become larger and processors become faster, it is necessary to increase battery capacities of the portable devices to maintain or extend the use time of the portable devices. However, as battery capacity increases, battery charging time increases substantially, which is undesirable for most users of portable devices.
In order to maintain the battery charging time constant or shorten the battery charging time, the output power of the charger and the adapter needs to be increased. Fast charging protocols such as those proposed by american college, watson technologies, and taiwan co-generation technologies, and power supply output voltage regulation protocols such as PD2.0, PD3.0 protocols, etc., which require higher average efficiency and smaller form factor in addition to output voltage variability, have emerged with the advent of such demands, and thus, the need for a synchronous rectification control mechanism in a switching power supply circuit.
Disclosure of Invention
In view of one or more of the above-described problems, the present invention provides a switching power supply circuit.
The switching power supply circuit according to the embodiment of the invention comprises a first transformer, a second transformer, a first pulse width modulation control chip positioned on the secondary side of the first transformer, a second pulse width modulation control chip positioned on the primary side of the first transformer, and a first power switch connected between the primary winding of the first transformer and a reference ground, wherein: the electric energy provided by the alternating current power supply is transmitted from the circuit input end of the switching power supply circuit to the circuit output end through the first transformer; the first PWM control chip transmits a PWM control signal for controlling the on and off of the first power switch to the second PWM control chip through a second transformer; the second PWM control chip controls the first power switch to be switched on and off based on the PWM control signal from the first PWM control chip.
Drawings
The invention may be better understood from the following description of specific embodiments thereof taken in conjunction with the accompanying drawings, in which:
fig. 1 shows a circuit diagram of a conventional switching power supply circuit with a synchronous rectification control mechanism;
FIG. 2 illustrates an internal block diagram of the PWM control chip shown in FIG. 1;
3A-3B are waveform diagrams illustrating the feedback divided voltage of the output voltage VO and the current detection voltage Vcs when the PWM control chip operates in Discontinuous Conduction Mode (DCM) and Continuous Conduction Mode (CCM), respectively;
fig. 4 shows a circuit diagram of a switching power supply circuit according to an embodiment of the invention;
FIG. 5 is an internal block diagram of a PWM control chip located on the secondary side of the transformer T1 shown in FIG. 4;
FIG. 6 is an internal block diagram of a PWM control chip located on the primary side of the transformer T1 shown in FIG. 4;
FIG. 7 shows a circuit diagram of the ramp generator shown in FIG. 5;
FIG. 8 illustrates a circuit diagram of a switching power supply circuit with a synchronous rectification control mechanism in accordance with an embodiment of the present invention;
fig. 9 shows an internal block diagram of a pulse width modulation control chip located on the secondary side of the transformer T1 shown in fig. 8.
Detailed Description
Features and exemplary embodiments of various aspects of the present invention will be described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is in no way limited to any specific configuration and algorithm set forth below, but rather covers any modification, replacement or improvement of elements, components or algorithms without departing from the spirit of the invention. In the drawings and the following description, well-known structures and techniques are not shown in order to avoid unnecessarily obscuring the present invention.
Fig. 1 shows a circuit diagram of a conventional switching power supply circuit with a synchronous rectification control mechanism. In the switching power supply circuit shown in fig. 1, a synchronous rectification control chip (SRIC) is located on the secondary side of the transformer T1, which controls on and off of a power switch M2 connected between the secondary winding of the transformer T1 and the circuit output terminal by detecting whether the transformer T1 is in a freewheeling state (i.e., a state in which energy stored in the transformer is discharged to the circuit output terminal); a pulse width modulation control chip (PWMIC) is located at the primary side of the transformer T1, and controls the on and off of a power switch M1 connected between the primary winding of the transformer T1 and the reference ground by detecting a change in the output voltage at the output terminal of the circuit and a change in the primary current flowing through the primary winding of the transformer T1.
Specifically, the synchronous rectification control chip detects whether the transformer T1 is in a freewheeling state through the VD terminal, controls the power switch M2 to be in a conducting state when the transformer T1 is detected to be in the freewheeling state, and controls the power switch M2 to be changed from the conducting state to the off state when the end of freewheeling of the transformer T1 or the change of the power switch M1 from the off state to the conducting state is detected.
Since the pwm control chip and the synchronous rectification control chip independently control the on and off of the power switch M1 and the power switch M2, respectively, under certain conditions (for example, dynamic load switching or short circuit conditions), there are situations where the power switch M1 and the power switch M2 are simultaneously turned on in a short time, which may cause the transient peak current flowing through the power switch M1 and the power switch M2 to be very large, thereby causing damage to these power switches or causing a machine explosion.
Fig. 2 shows an internal block diagram of the pwm control chip shown in fig. 1. In the pwm control chip shown in fig. 2, voltage dividing resistors Ru and Rd divide the feedback voltage VFB of the output voltage VO from the secondary side of the transformer T1 and the output end of the characterization circuit, so as to generate a feedback divided voltage of the output voltage VO; a Leading Edge Blanking (LEB) circuit performs leading edge blanking processing on a current detection voltage Vcs generated on a current detection resistor Rs by a primary current flowing through a primary winding of a transformer T1 to generate a blanking voltage of the current detection voltage Vcs; the PWM comparator generates a PWM modulation signal based on the feedback voltage division of the output voltage VO and the blanking voltage of the current detection voltage Vcs; the oscillator generates an oscillation signal with a fixed pulse width based on a feedback voltage VFB representing the output voltage VO; the RS flip-flop and the driver generate a PWM control signal for controlling on and off of the power switch M1 based on the PWM modulation signal from the PWM comparator and the oscillation signal from the oscillator.
Here, the voltage at the CS terminal of the pwm control chip, that is, the current detection voltage Vcs generated on the current detection resistor Rs by the primary side current flowing through the primary side winding of the transformer T1 is represented by the following equation 1, and the rising slope Kr _ CS of the current detection voltage Vcs is represented by the following equation 2:
where VIN is a line voltage obtained by the switching power supply circuit shown in fig. 1 after performing electromagnetic interference (EMI) filtering and rectification on an Alternating Current (AC) input voltage, Lm is an inductance of a primary winding of the transformer T1, ton is a conduction time of the power switch M1, and Rs is a resistance value of the current detection resistor Rs.
After the switching power supply circuit shown in fig. 1 enters the closed-loop operation, the input voltages received by the two input terminals of the PWM comparator are equal, that is, the feedback divided voltage of the output voltage VO and the blanking voltage of the current detection voltage Vcs are equal.
Fig. 3A-3B show waveforms of the feedback divided voltage of the output voltage VO and the current detection voltage Vcs when the pwm control chip operates in the Discontinuous Conduction Mode (DCM) and the Continuous Conduction Mode (CCM), respectively.
As shown in fig. 3A, in the DCM mode, a voltage at the FB terminal of the pwm control chip, i.e. a feedback voltage VFB representing the output voltage VO, is:
as shown in fig. 3B, in the CCM mode, the voltage at the FB terminal of the pwm control chip, i.e., the feedback voltage VFB representing the output voltage VO, is: :
wherein, Ru and Rd are the resistance values of the voltage dividing resistors Ru and Rd connected between the FB terminal and the system ground in the PWM control chip, Vcs _ peak is the maximum value of the current detection voltage Vcs, and Vcs0 is the minimum value of the current detection voltage Vcs.
Here, the voltage at the CS terminal of the pwm control chip, that is, the primary side current flowing through the primary side winding of the transformer T1, has a falling slope Kf _ CS of the current detection voltage Vcs generated across the current detection resistor Rs as:
kf _ cs ═ Vcs/tdem ═ Np/Ns · (Vo + Vd) · Rs/Lm (equation 5)
Where Np and Ns are the number of turns of the primary and secondary windings of transformer T1, respectively, and Vd is the turn-on voltage of a diode connected between the secondary winding of transformer T1 and the circuit output.
In the switching power supply circuit described in conjunction with fig. 1, fig. 2, and fig. 3A to 3B, when the load is momentarily loaded or unloaded, the power switch M1 and the power switch M2 on the primary side and the secondary side of the transformer T1 are turned on simultaneously, which increases the risk of damage to the switching power supply circuit.
Fig. 4 shows a circuit diagram of a switching power supply circuit according to an embodiment of the present invention. Fig. 5 shows an internal block diagram of the pwm control chip located on the secondary side of the transformer T1 shown in fig. 4. Fig. 6 shows an internal block diagram of the pwm control chip located on the primary side of the transformer T1 shown in fig. 4. A switching power supply circuit according to an embodiment of the present invention is described in detail below with reference to fig. 4 to 6.
As shown in fig. 4, the switching power supply circuit according to the embodiment of the present invention includes transformers T1 and T2, a pwm control chip 302 on the secondary side of the transformer T1, a pwm control chip 304 on the primary side of the transformer T1, and a power switch M1 connected between the primary winding of the transformer T1 and ground. Here, the electric power supplied from the ac power supply is transmitted from the circuit input terminal to the circuit output terminal of the switching power supply circuit via the transformer T1; the PWM control chip 302 transmits a PWM control signal for controlling the on and off of the power switch M1 to the PWM control chip 304 via the transformer T2 (here, the transformer T2 isolates the PWM control signal at the PWM terminal of the PWM control chip 304 from the PWM control signal at the PWM terminal of the PWM control chip 302); the PWM control chip 304 controls the power switch M1 to turn on and off based on the PWM control signal from the PWM control chip 302.
As shown in fig. 5, in the pulse width modulation control chip 302, an Error Amplifier (EA) generates an error amplification signal based on the voltage at the FB terminal (i.e., the representative voltage of the output voltage VO) and the reference voltage Vref; the ramp generator generates a ramp voltage signal based on a line voltage obtained by EMI filtering and rectifying an ac input voltage of the switching power supply circuit, a voltage at the PWM terminal (i.e., a PWM control signal output from the pulse width modulation control chip 302), and a voltage at the VDD terminal (i.e., an output voltage VO); a PWM comparator generates a PWM modulation signal based on the error amplification signal from the error amplifier and the ramp voltage signal from the ramp generator; the oscillator generates an oscillation signal with a fixed pulse width based on the ramp voltage signal from the ramp generator; the RS flip-flop and the driver generate a PWM control signal based on a PWM modulation signal from the PWM comparator and an oscillation signal from the oscillator. Here, the representative voltage of the output voltage VO is generated by dividing the output voltage VO by voltage dividing resistors R1 and R2.
As shown in fig. 6, in the PWM control chip 304, the PWM detection unit restores and shapes the PWM control signal from the PWM control chip 302; the driver controls the on and off of the power switch M1 based on the PWM control signal restored and shaped by the PWM detection unit.
Here, when the PWM control signal output by the PWM control chip 302 is "1" (i.e., high level), the GATE terminal of the PWM control chip 304 outputs a drive signal of high level to control the power switch M1 to be in a conductive state; when the PWM control signal output by the PWM control chip 302 is "0" (i.e., low level), the GATE terminal of the PWM control chip 304 outputs a low level driving signal to control the power switch M1 to be in an off state.
In order to achieve the same effect as the PWM control manner of the switching power supply circuits described in conjunction with fig. 1, 2, and 3A to 3B in the DCM mode and the CCM mode, the rising/falling slope of the ramp voltage signal generated by the ramp generator shown in fig. 5 needs to be the same as or in proportion to the rising/falling slope of the current detection voltage Vcs in the switching power supply circuits described in conjunction with fig. 1, 2, and 3A to 3B.
As can be seen from the equations of the rising/falling slopes Kr _ cs/Kf _ cs of the current detection voltage Vcs in the switching power supply circuits described with reference to fig. 1, 2, and 3A-3B, the rising slope Kr _ cs and VIN of the current detection voltage Vcs are proportional, and the falling slope Kf _ cs and VO + Vd of the current detection voltage Vcs are proportional. Therefore, as long as the ramp generator shown in fig. 5 generates the ramp voltage signal whose rising slope is proportional to VIN and whose falling slope is proportional to VO + Vd, the PWM control method of the switching power supply circuit according to the embodiment of the present invention may be completely equivalent to the PWM control method of the switching power supply circuit described in conjunction with fig. 1, fig. 2, and fig. 3A-3B.
In the switching power supply circuit shown in fig. 4, when the power switch M1 is in the on state, the voltage across the secondary winding of the transformer T1 is VIN × Ns/Np; in the case where transformer T1 is a flyback transformer, the voltage on the secondary winding of transformer T1 is negative with respect to ground, i.e., -VIN × Ns/Np. Similar to the switching power supply circuits described in conjunction with fig. 1, 2, and 3A-3B, Np and Ns are the number of turns in the primary and secondary windings of transformer T1, respectively, and VIN is the line voltage resulting from EMI filtering and rectifying the AC input voltage by the switching power supply circuit shown in fig. 4.
Fig. 7 shows a circuit diagram of the ramp generator shown in fig. 5. In the ramp generator shown in fig. 7, the operational amplifier (OPA) clamps the voltage at VD terminal to "0", so the current flowing through the operational amplifier is (VIN × Ns/Np)/R0, where R0 is the resistance of the resistor R0 connected between the circuit output and VD terminal; 1/M mirror current Ic flowing through the operational amplifier charges a capacitor Cramp when the PWM control signal is '1'; the voltage (namely, the output voltage VO) at the VDD terminal is superposed with a fixed voltage Va to generate a discharge current Id after passing through a voltage-to-current module; discharging the capacitor Cramp by the discharging current Id when the PWM control signal is 0; the charging and discharging of the capacitor Cramp by the Ic/Id current forms a ramp voltage signal Vramp.
Here, the 1/M mirror current Ic and the discharge current Id are represented by the following equations 6 and 7, respectively:
where R0 is the resistance of the resistor R0 in fig. 4, M is the mirror coefficient of the current mirror shown in fig. 7, and Rv is the resistance of the resistor in the voltage-to-current module shown in fig. 7.
Therefore, the rising slope Kr _ ramp and the falling slope Kf _ ramp of the ramp voltage signal Vramp are as follows:
let Kr _ cs be Kr _ ramp
After the system determines, Ns, Np, Lm, Rs are all fixed values. Therefore, the rising slope of the ramp voltage signal Vramp in fig. 5 and the rising slope of the current detection voltage Vcs in fig. 1 can be made equal by choosing M, R0, Cramp satisfying equation 10.
Similarly, let Kf _ cs be Kf _ ramp
In equation 11, VDD is VO, and Va is Vd, so that:
after the system determines, Ns, Np, Lm, Rs are all fixed values. Therefore, the falling slope of the ramp voltage signal Vramp in fig. 5 and the falling slope of the current detection voltage Vcs in fig. 1 can be made equal by selecting Rv, Cramp satisfying equation 12.
In summary, the pulse width modulation control chip 302 selects appropriate M, Rv, and Cramp to make the rising slope and the falling slope of the ramp voltage signal Vramp in fig. 5 the same as the rising slope and the falling slope of the current detection voltage Vcs in fig. 1, so that the PWM control method according to the embodiment of the present invention is completely equivalent to the conventional PWM control method.
Fig. 8 shows a circuit diagram of a switching power supply circuit with a synchronous rectification control mechanism according to an embodiment of the present invention. Fig. 9 shows an internal block diagram of a pulse width modulation control chip located on the secondary side of the transformer T1 shown in fig. 8. In the switching power supply circuits shown in fig. 8 and 9, when the PWM control signal is "1", the power switch M1 connected between the primary winding of the transformer T1 and the reference ground is in the on state, and the power switch M2 connected between the secondary winding of the transformer T1 and the circuit output terminal is in the off state, so that the problem of short-time primary-secondary common can be solved; meanwhile, when the PWM control signal is "0", the Synchronous Rectification (SR) detection module detects whether the transformer T1 is in a freewheeling state, controls the power switch M2 to be in a conducting state when the transformer T1 is detected to be in a freewheeling state (i.e., the voltage at the VD terminal is negative), and controls the power switch M2 to be in a turning-off state when the end of freewheeling is detected (i.e., the voltage at the VD terminal is positive).
It will be appreciated by persons skilled in the art that the above embodiments are illustrative and not restrictive. Different features which are present in different embodiments may be combined to advantage. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art upon studying the drawings, the specification, and the claims. Any reference signs in the claims shall not be construed as limiting the scope. The functions of the various parts appearing in the claims may be implemented by a single hardware or software module. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
Claims (5)
1. A switching power supply circuit comprises a first transformer, a second transformer, a first pulse width modulation control chip located on the secondary side of the first transformer, a second pulse width modulation control chip located on the primary side of the first transformer, and a first power switch connected between the primary winding of the first transformer and a reference ground, wherein:
the electric energy provided by the alternating current power supply is transmitted from the circuit input end of the switching power supply circuit to the circuit output end through the first transformer;
the first PWM control chip transmits a PWM control signal for controlling the on and off of the first power switch to the second PWM control chip through the second transformer;
the second PWM control chip controls the first power switch to be turned on and off based on the PWM control signal from the first PWM control chip,
wherein the first pwm control chip includes an error amplifier, a ramp generator, a pwm comparator, an oscillator, an RS flip-flop, and a first driver, wherein:
the error amplifier generates an error amplification signal based on a characteristic voltage of an output voltage of the switching power supply circuit and a reference voltage;
the ramp generator generates a ramp voltage signal based on a line voltage obtained by performing electromagnetic interference filtering and rectification on an alternating-current input voltage of the switching power supply circuit, the pulse width modulation control signal and an output voltage of the switching power supply circuit, wherein the rising slope of the ramp voltage signal is proportional to the magnitude of the alternating-current input voltage of the switching power supply circuit, and the falling slope of the ramp voltage signal is proportional to the sum of the following two voltages: an output voltage of the switching power supply circuit; and a conduction voltage of a diode connected between a secondary winding of the first transformer and the circuit output terminal of the switching power supply circuit;
the pulse width modulation comparator generates a pulse width modulation signal based on the error amplification signal and the ramp voltage signal;
the oscillator generates an oscillation signal with fixed pulse width based on the ramp voltage signal;
the RS flip-flop and the first driver generate the pulse width modulation control signal based on the pulse width modulation signal and the oscillation signal.
2. The switching power supply circuit of claim 1, wherein the second pwm control chip includes a pwm detection unit and a second driver, wherein:
the pulse width modulation detection unit restores and shapes the pulse width modulation control signal from the first pulse width modulation control chip;
the second driver controls the first power switch to be turned on and off based on the pwm control signal restored and shaped by the pwm detection unit.
3. The switching power supply circuit according to claim 1, wherein the ramp generator generates the ramp voltage signal by charging and discharging of a capacitor, a charging current for the capacitor depending on a line voltage based on electromagnetic interference filtering and rectifying an alternating input voltage of the switching power supply circuit, a turn ratio of a secondary winding to a primary winding of the first transformer, and a resistance value of a resistor connected between a negative input terminal of an operational amplifier in the ramp generator and a circuit output terminal of the switching power supply circuit, a discharging current for the capacitor depending on an output voltage of the switching power supply circuit and a predetermined voltage.
4. The switching power supply circuit of claim 1, further comprising a second power switch connected between the secondary winding of the first transformer and a circuit output of the switching power supply circuit, wherein
When the pulse width modulation control signal is at a high level, the first pulse width modulation control chip controls the first power switch to be in a conducting state and controls the second power switch to be in a turn-off state,
when the pulse width modulation control signal is at a low level, the first pulse width modulation control chip controls the first power switch to be in an off state, detects whether the first transformer is in a freewheeling state, controls the second power switch to be in an on state when the first transformer is detected to be in the freewheeling state, and controls the second power switch to be changed from the on state to the off state when the first transformer is detected to be in the freewheeling state.
5. The switching power supply circuit according to claim 4, wherein the first pulse width modulation control chip further comprises a synchronous rectification detection unit that detects whether the first transformer is in a freewheeling state, controls the second power switch to be in a conducting state when it is detected that the first transformer is in the freewheeling state, and controls the second power switch to be changed from the conducting state to the off state when it is detected that the first transformer is freewheeling ended.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810910213.6A CN109286321B (en) | 2018-08-10 | 2018-08-10 | Switching power supply circuit |
| TW107141314A TWI666874B (en) | 2018-08-10 | 2018-11-20 | Switching power supply circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810910213.6A CN109286321B (en) | 2018-08-10 | 2018-08-10 | Switching power supply circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109286321A CN109286321A (en) | 2019-01-29 |
| CN109286321B true CN109286321B (en) | 2021-02-26 |
Family
ID=65182735
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810910213.6A Active CN109286321B (en) | 2018-08-10 | 2018-08-10 | Switching power supply circuit |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN109286321B (en) |
| TW (1) | TWI666874B (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5424932A (en) * | 1993-01-05 | 1995-06-13 | Yokogawa Electric Corporation | Multi-output switching power supply having an improved secondary output circuit |
| CN105873276A (en) * | 2016-05-03 | 2016-08-17 | 昂宝电子（上海）有限公司 | System for providing output current to one or more light emitting diodes |
| CN205596020U (en) * | 2015-12-31 | 2016-09-21 | 广州金升阳科技有限公司 | Switching power supply's feedback control circuit |
| CN108173434A (en) * | 2018-01-15 | 2018-06-15 | 昂宝电子（上海）有限公司 | Switching power circuit |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07312863A (en) * | 1994-05-13 | 1995-11-28 | Nippon Steel Corp | Switching regulator |
| US6366070B1 (en) * | 2001-07-12 | 2002-04-02 | Analog Devices, Inc. | Switching voltage regulator with dual modulation control scheme |
| US7245113B2 (en) * | 2004-05-21 | 2007-07-17 | Intersil Corporation | High light load efficiency synchronous buck regulator with pulse skipping control |
| CN102664525B (en) * | 2012-05-08 | 2014-08-27 | 成都芯源系统有限公司 | Switching power supply circuit |
| CN207625446U (en) * | 2017-05-31 | 2018-07-17 | 昂宝电子（上海）有限公司 | Switching power circuit |
-
2018
- 2018-08-10 CN CN201810910213.6A patent/CN109286321B/en active Active
- 2018-11-20 TW TW107141314A patent/TWI666874B/en active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5424932A (en) * | 1993-01-05 | 1995-06-13 | Yokogawa Electric Corporation | Multi-output switching power supply having an improved secondary output circuit |
| CN205596020U (en) * | 2015-12-31 | 2016-09-21 | 广州金升阳科技有限公司 | Switching power supply's feedback control circuit |
| CN105873276A (en) * | 2016-05-03 | 2016-08-17 | 昂宝电子（上海）有限公司 | System for providing output current to one or more light emitting diodes |
| CN108173434A (en) * | 2018-01-15 | 2018-06-15 | 昂宝电子（上海）有限公司 | Switching power circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| TWI666874B (en) | 2019-07-21 |
| CN109286321A (en) | 2019-01-29 |
| TW202010259A (en) | 2020-03-01 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8923021B2 (en) | Control circuit and system for switch mode power supply | |
| EP1605576A1 (en) | Device and method for extending the input voltage range of a DC/DC converter | |
| US11611282B2 (en) | Switching power circuit for charging a battery | |
| KR100806774B1 (en) | Ac-to-dc converter and method for converting ac to dc using the same | |
| KR20130043923A (en) | Apparatus for power supplying and image forming apparatus including the same | |
| US20110001460A1 (en) | Lower power controller for dc to dc converters | |
| EP1531541B1 (en) | Power supply having reduced-power mode | |
| CN110417101B (en) | Battery charging circuit and battery charging method | |
| JPWO2014188711A1 (en) | DC power supply circuit | |
| EP2463993A2 (en) | Switching power supply and display device provided with same | |
| US5570277A (en) | Switching power supply apparatus | |
| TWM561363U (en) | Switching power supply circuit | |
| US20120044724A1 (en) | Switching power supply apparatus | |
| US7974110B2 (en) | Switching power supply unit and method for setting switching frequency | |
| CN210669601U (en) | Battery charging circuit | |
| CN109286321B (en) | Switching power supply circuit | |
| CN113726175B (en) | Conversion device, controller and power supply control method thereof | |
| CN216290693U (en) | Conversion device and controller | |
| CN211266788U (en) | Switching power supply circuit | |
| JPH05300667A (en) | Switching power supply type charger | |
| US7468897B2 (en) | Rectifier without active switches | |
| US6982881B2 (en) | Current detecting circuit and power converter having the same | |
| JP3402031B2 (en) | DC power supply | |
| EP3723259A1 (en) | Switched mode power supply | |
| JP3672452B2 (en) | Power supply circuit and power supply device using the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |