CN2720717Y - Converter with automatic switching-over pulse width/frequency modulation mode - Google Patents
Converter with automatic switching-over pulse width/frequency modulation mode Download PDFInfo
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- CN2720717Y CN2720717Y CN 200420066802 CN200420066802U CN2720717Y CN 2720717 Y CN2720717 Y CN 2720717Y CN 200420066802 CN200420066802 CN 200420066802 CN 200420066802 U CN200420066802 U CN 200420066802U CN 2720717 Y CN2720717 Y CN 2720717Y
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Abstract
The utility model relates to a converter with an automatic switching-over pulse width/frequency modulation mode, which is connected with a load through a power switch drive unit. The utility model comprises an activating control unit which outputs an actuating energy generation signal, a PWM/PFM automatic switching control circuit which is connected with the activating control unit to receive the actuating energy generation signal and can output a selection signal, a PWM control unit which is connected with the PWM/PFM automatic switching control circuit, a power switch drive unit and the load, and a PFM control unit which is connected with the PWM/PFM automatic switching control circuit, the power switch drive unit and the load can receive an electric voltage feedback signal output by the load and a load current signal output by the power switch drive unit and can output a current comparison signal to the PWM/PFM automatic switching control circuit. When the load declines, the switch frequency of the switch of the utility model is reduced, and then the switching loss of the switch is reduced for maintaining higher working efficiency.
Description
Technical field
The utility model relates to a kind of transducer and PWM/PFM automatic switching control circuit with automatic switchover pulse duration/frequency modulating pattern, particularly relates to a kind ofly can automaticallying switch the direct current of two kinds of mode of operations of pulse-width modulation technology (PWM) and pulse-frequency modulation technology (PFM) to direct current or exchange transducer to direct current with load variations.
Background technology
Because electronic technology is flourish, electronic product is widely used by people, and therefore, the supply of electric power problem that electronic product uses becomes very important problem.At present, electronic product generally uses the power supply method of supplying of switched to realize the supply of electric power, and switched is the switch operating that can carry out switch by pulse-width modulation technology (PWM) or two kinds of mode of operations of pulse-frequency modulation technology (PFM).
When electronic product carries out work under full load or middle loading condition, normally come the change action of control its switch by pulse-width modulation technology (PMW), its working loss has conduction loss and switch handoff loss.But, electronic product is when underloading, if still come the change action of control its switch by pulse-width modulation technology (PWM), this moment, conduction loss can descend because electronic product is in underloading, but since the switch switching frequency immobilize, so the switch handoff loss can not descend and not reduce along with load, thereby when underloading, use the mode of operation of pulse-width modulation technology (PWM), then its whole efficiency reduces.
Therefore, when electronic product carries out work under the underloading condition, normally come the change action of control its switch by pulse-frequency modulation technology (PFM).Promptly when load descended, the switching frequency of switch also descended thereupon, thereby can reduce the switch handoff loss, keeps higher operating efficiency.
Can know that from above-mentioned explanation electronic product is can utilize to switch pulse-width modulation technology (PWM) and two kinds of mode of operations of pulse-frequency modulation technology (PFM), in order to improve the operating efficiency of product when load variations.
Summary of the invention
Technical problem to be solved in the utility model is to provide a kind of transducer with automatic switchover pulse duration/frequency modulating pattern, switch consume and do not descend and reduce to solve prior art switch when the underloading, make the problem that whole efficiency reduces along with load.
To achieve these goals, the utility model provides a kind of transducer with automatic switchover pulse duration/frequency modulating pattern, be connected to load by a power switch driver element, boost conversion one direct current electric power, its characteristics are, include: one activates control unit, and output one activates enable signal; One PWM/PFM automatic switching control circuit is connected in described activation control unit and receives described activation enable signal, and signal is selected in output one; One PWM control unit, be connected in described PWM/PFM automatic switching control circuit, described power switch driver element and described load, receive a load current signal of a voltage feedback signal of described load output, the output of described power switch driver element, and export an error signal to described PWM/PFM automatic switching control circuit, simultaneously, receive described selection signal, export a pwm control signal and give described power switch driver element; An and PFM control unit, be connected in described PWM/PFM automatic switching control circuit, described power switch driver element and described load, receive a load current signal of a voltage feedback signal of described load output, the output of described power switch driver element, and export an electric current comparison signal to described PWM/PFM automatic switching control circuit, simultaneously, receive described selection signal, export a PFM control signal and give described power switch driver element.
Above-mentioned transducer with automatic switchover pulse duration/frequency modulating pattern, its characteristics be, the described error signal of described PWM control unit output is made comparisons computing and got by a described voltage feedback signal and a reference voltage.
Above-mentioned transducer with automatic switchover pulse duration/frequency modulating pattern, its characteristics be, the described electric current comparison signal of described PFM control unit output is made comparisons computing and got by a described load current signal and a reference current.
Above-mentioned transducer with automatic switchover pulse duration/frequency modulating pattern, its characteristics are that described PWM/PFM automatic switching control circuit includes: a reference voltage generation unit, export at least one reference voltage signal; One PWM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described error signal, exports a PWM comparison signal; One PWM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described error signal, exports a PFM comparison signal; One first flip-flop is connected in described PWM comparing unit and described PFM comparing unit, and a reset signal is exported in computing; One AND circuit, output one and gate signal; And one second flip-flop, be connected in described first flip-flop and described AND circuit, receive described reset signal and described and gate signal, described selection signal is exported in computing.
Above-mentioned transducer with automatic switchover pulse duration/frequency modulating pattern, its characteristics are, described AND circuit is connected in described PFM control unit and described second flip-flop, receive described electric current comparison signal and described selection signal, described electric current comparison signal and described selection signal are carried out and (AND) logical operation, export described and gate signal.
Above-mentioned transducer with automatic switchover pulse duration/frequency modulating pattern, its characteristics are that described first flip-flop is a R-S flip-flop.
Above-mentioned transducer with automatic switchover pulse duration/frequency modulating pattern, its characteristics are that described second flip-flop is a R-S flip-flop.
The utility model also provides a kind of PWM/PFM automatic switching control circuit, receive a feedback signal of a PWM control unit and PFM control unit output, control by an activation control unit, output one selects signal to described PWM control unit and described PFM control unit, select switch control unit, its characteristics are, include: a reference voltage generation unit, export at least one reference voltage signal; One PWM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described feedback signal, exports a PWM comparison signal; One PFM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described feedback signal, exports a PFM comparison signal; One first flip-flop is connected in described PWM comparing unit and described PFM comparing unit, and a reset signal is exported in computing; One AND circuit, output one and gate signal; And one second flip-flop, be connected in described first flip-flop and described AND circuit, receive described reset signal and described and gate signal, described selection signal is exported in computing.
Said PWM/PFM automatic switching control circuit, its characteristics are, described AND circuit is connected in described PFM control unit and described second flip-flop, receive described feedback signal and described selection signal, feedback signal and described selection signal are carried out and (AND) logical operation, export described and gate signal.
Said PWM/PFM automatic switching control circuit, its characteristics are that described first flip-flop is a R-S flip-flop.
Said PWM/PFM automatic switching control circuit, its characteristics are that described second flip-flop is a R-S flip-flop.
Effect of the present utility model, be to utilize and switch pulse-width modulation technology (PWM) and two kinds of mode of operations of pulse-frequency modulation technology (PFM), when load descended, the switching frequency of switch descended thereupon, thereby can reduce the switch handoff loss, keep higher operating efficiency.
Below in conjunction with the drawings and specific embodiments the utility model is described in detail, but not as to qualification of the present utility model.
Description of drawings
Fig. 1 is the converter circuit block schematic diagram that the utlity model has automatic switchover pulse duration/frequency modulating pattern;
Fig. 2 is the circuit box schematic diagram of the utility model PWM control unit;
Fig. 3 is the circuit box schematic diagram of the utility model PFM control unit;
Fig. 4 is the utility model PWM/PFM automatic switching control circuit block schematic diagram;
Fig. 5 is the utility model signal output waveform schematic diagram.
Wherein, description of drawings:
102-activates control unit
The 106-PWM control unit
The 1060-current detecting unit, 1062-quiet hour control unit
1064-PWM limits electric current, 1066-PWM oscillator
The 1068-ramp generator, the 1069-adder
The 108-PFM control unit
The 1080-current detecting unit
110-power switch driver element
The 112-load
The 20-PWM/PFM automatic switching control circuit
The 202-PWM comparing unit
The 204-PFM comparing unit
206-reference voltage generation unit
208-first flip-flop
210-second flip-flop
The 212-AND circuit
Embodiment
Please refer to Fig. 1, for the utlity model has the converter circuit block schematic diagram of automatic switchover pulse duration/frequency modulating pattern.The utility model utilizes a PWM/PFM automatic switching control circuit 20 to be connected in one and activates control unit 102, an one PWM control unit 106 and a PFM control unit 108, activating control unit 102 transmission one activation activation (enable) signal gives PWM/PFM automatic switching control circuit 20 and controls its activation action, simultaneously, after the PWM/PFM automatic switching control circuit 20 activations action, PWM control unit 106 and PFM control unit 108 are to transmit one respectively to feed back signal to PWM/PFM automatic switching control circuit 20, select the foundation of signal so that 20 outputs one of PWM/PFM automatic switching control circuit to be provided.PWM/PFM automatic switching control circuit 20 transmits selects signal to PWM control unit 106 and PFM control unit 108, in order to activation control unit action wherein.And the control unit of selected signal activation is exported a control signal and is given the power switch driver element 110 that is connected in control unit.Control signal is the change action of power controlling switch drive unit 110, uses to a load 112 that is connected in power switch driver element 110 so that a direct current electric power (not indicating) to be provided.
Cooperate Fig. 1, please refer to Fig. 2, be the circuit box schematic diagram of the utility model PWM control unit.Wherein, PWM control unit 106 is connected in described power switch driver element 110 and this load 112 simultaneously, obtain a voltage feedback signal from this load 112, and with this voltage feedback signal and the preset reference voltage VREF computing action of making comparisons, in order to export an error signal ES1 to this PWM/PFM automatic switching control circuit 20.And, utilize inner current detecting unit 1060 to obtain a load current signal of power switch driver element 110.
Voltage feedback signal that PWM control unit 106 is obtained and load current signal, after being computing by each circuit units such as inner quiet hour control unit 1062, PWM restriction electric current 1064, PWM oscillator 1066, ramp generator 1068 and adders 1069, transmit activation according to PWM/PFM automatic switching control circuit 20 and select signal, give this power switch driver element 110 in order to export a pwm control signal, thereby control the change action of this power switch driver element 110, it is PWM enable signal PWMEN that signal is selected in this activation.
Cooperate Fig. 1, please refer to Fig. 3, be the circuit box schematic diagram of the utility model PFM control unit.PFM control unit 108 is connected in power switch driver element 110 and load 112 simultaneously, obtains a voltage feedback signal from load 112, and with voltage feedback signal and the preset reference voltage VREF computing action of making comparisons, in order to export an error signal ES2.And utilize inner current detecting unit 1080 to obtain a load current signal of power switch driver element 110.Make comparisons computing action of a load current signal CS and a preset reference electric current CLS is in order to export an electric current comparison signal ICS to PWM/PFM automatic switching control circuit 20.
Error signal ES2 that PFM control unit 108 is obtained and load current signal, after being computing by inner each circuit unit, send activation according to PWM/PFM automatic switching control circuit 20 and select signal, give power switch driver element 110 in order to export a PFM control signal, thereby control the change action of this power switch driver element 110.
Cooperate Fig. 1, please refer to Fig. 4, be the utility model PWM/PFM automatic switching control circuit block schematic diagram.PWM/PFM automatic switching control circuit 20 is to be connected in simultaneously by PWM comparing unit 202 and PFM comparing unit 204 to activate control unit 102, PWM control unit 106 and a reference voltage generation unit 206, is to receive by the error signal ES1 that activates activation enable signal that control unit 102 sends, sent by PWM control unit 106 and by the reference voltage signal of reference voltage generation unit 206 outputs.PWM comparing unit 202 and PFM comparing unit 204 be according to activating enable signal, in order to carrying out the comparison operation of reference voltage signal and error signal ES1 respectively, and exports a PWM comparison signal S1 and a PFM comparison signal S2 respectively.In the above-mentioned explanation, reference voltage generation unit 206 outputs to the reference voltage signal VPWM of PWM control unit 106 greater than the reference voltage signal VPFM that outputs to PFM control unit 108.
With reference to figure 4, PWM/PFM automatic switching control circuit 20 is to utilize two inputs of one first flip-flop 208 to be connected to PWM comparing unit 202 and PFM comparing unit 204, and one second flip-flop 210 be connected in the output of first flip-flop 208, first flip-flop 208 is to receive PWM comparison signal S1 and PFM comparison signal S2, thereby computing is exported a reset signal to second flip-flop 210.One input of second flip-flop 210 is connected in the output of first flip-flop 208, and another input is set the output that is connected in an AND circuit 212.Second flip-flop 210 receives one and gate signal of reset signal and AND circuit 212 outputs, and signal is selected in union output one.This selection signal is connected in the PWM control unit 106 and 108 actions (with reference to figure 1) of PFM control unit of PWM/PFM automatic switching control circuit 20 in order to activation, can be divided into a PWM enable signal PWMEN and a PFM enable signal PFMEN.This AND circuit 212 obtains the electric current comparison signal ICS that PFM enable signal PFMEN and PFM control unit 108 are sent respectively, and with PFM enable signal PFMEN and electric current comparison signal ICS do with (AND) logical operation after, output and gate signal.In the above-mentioned explanation, first flip-flop 208 and second flip-flop 210 are to be all the R-S flip-flop.
Cooperate Fig. 3, Fig. 4, please refer to Fig. 5, be the utility model signal output waveform schematic diagram.As shown in Figure 5, when time t0-t1, error signal ES1 is no show reference voltage signal VPFM still, still be lower than reference voltage signal VPFM, at this moment, PWM comparison signal S1 is an electronegative potential, simultaneously, PFM comparison signal S2 is a high potential, sets end (S) because the high potential of PFM comparison signal S2 is sent to one of first flip-flop 208, so the reset signal S4 of first flip-flop, 208 outputs is high potentials.Reset signal S4 is a replacement end (R) that is sent to second flip-flop 210, and so, second flip-flop 210 is selection signals of output one electronegative potential, and the selection signal of this electronegative potential is PFM enable signal PFMEN.At this moment, load current signal CS so electric current comparison signal ICS is an electronegative potential, is that with gate signal S3 to one of second flip-flop 210 the setting of output electronegative potential hold (S) in time t0-t1 AND circuit 212 less than restriction electric current CLS, therefore, 210 outputs of second flip-flop keep original state.
With reference to figure 5, when time t1-t2, error signal ES1 is greater than reference voltage signal VPFM, but but still less than reference voltage signal VPWM, at this moment, PWM comparison signal S1 still keeps electronegative potential, and PFM comparison signal S2 goes back to electronegative potential by high potential.Because PFM comparison signal S1 and PFM comparison signal S2 are all electronegative potential, therefore the reset signal S4 of first flip-flop, 208 outputs still keeps high potential output.At this moment, load current signal CS is still less than restriction electric current CLS, and therefore, 210 outputs of second flip-flop keep original state.
With reference to figure 5, when time t2-t3, error signal ES1 is greater than reference voltage signal VPFM and reference voltage signal VPWM, at this moment, PWM comparison signal S1 is transformed into high potential by electronegative potential, PFM comparison signal S1 is transformed into high potential by electronegative potential, and PFM comparison signal S2 still remains electronegative potential.Because PWM comparison signal S1 is transformed into high potential by electronegative potential, institute is to become electronegative potential from the high potential transition to export through the reset signal S4 of first flip-flop, 208 outputs.At this moment, load current signal CS is greater than restriction electric current CLS, so electric current comparison signal ICS is a high potential.And when time t2, (S) held in setting to one of second flip-flop 210 with gate signal S3 of AND circuit 212 outputs one pulse wave high potential, with so that the selection signal of a high potential is exported in 210 transitions of second flip-flop, the selection signal of this high potential is PWM enable signal PWMEN.
At time t4-t5, error signal ES1 is less than reference voltage signal VPWM, but still greater than reference voltage signal VPFM.At this moment, PWM comparison signal S1 is transformed into electronegative potential by high potential, and PFM comparison signal S2 still remains electronegative potential.And the reset signal S4 of flip-flop 208 output this moment first remains electronegative potential output, and load current signal CS is less than restriction electric current CLS, so electric current comparison signal ICS is electronegative potential, and second flip-flop 210 still keeps the PWM enable signal PWMEN of high potential.
At time t5-t6, error signal ES1 is less than reference voltage signal VPWM and reference voltage signal VPRM.At this moment, PWM comparison signal S1 still keeps electronegative potential, and the reset signal S4 that the high potential of PFM comparison signal S2 is sent to 208 outputs of first flip-flop is a high potential.At this moment, load current signal CS is less than restriction electric current CLS, so electric current comparison signal ICS is an electronegative potential.And second flip-flop 210 is by the PWM enable signal PWMEN of high potential, resets to be output as PFM enable signal PFMEN.
Behind time t7, load current signal CS is greater than restriction electric current CLS, so electric current comparison signal ICS is a high potential.And when time t7, AND circuit 212 output one pulse wave high potential set end (S) for one of second flip-flop 210 with gate signal S3, with so that 210 transitions of second flip-flop are output as PWM enable signal PWMEN.
In sum, the utility model is a kind of transducer with automatic switchover pulse duration/frequency modulating pattern, can utilize PWM comparing unit and PFM comparing unit, be connected in a reference voltage generation unit simultaneously, activate control unit and PWM control unit, receive a reference voltage signal respectively, activate enable signal and feedback signal, in order to export a PWM comparison signal and a PFM comparison signal respectively, and be sent to one first flip-flop that is connected in PWM comparing unit and PFM comparing unit, output one reset signal after the first flip-flop computing.And, utilize one second flip-flop, be connected in first flip-flop and an AND circuit, receive a reset signal and a gate signal, exporting after computing can activation PWM control unit and the selection signal of PFM control unit.So, the utility model can allow electronic product when load variations, utilizes to switch pulse-width modulation technology (PWM) and two kinds of mode of operations of pulse-frequency modulation technology (PFM), to improve the operating efficiency of product.
Certainly; the utility model also can have other various embodiments; under the situation that does not deviate from the utility model spirit and essence thereof; those of ordinary skill in the art can make various corresponding changes and distortion according to the utility model, but these corresponding changes and distortion all should belong to the protection range of the utility model claim.
Claims (11)
1, a kind of transducer with automatic switchover pulse duration/frequency modulating pattern is connected to load by a power switch driver element, and boost conversion one direct current electric power is characterized in that, includes:
One activates control unit, and output one activates enable signal;
One PWM/PFM automatic switching control circuit is connected in described activation control unit and receives described activation enable signal, and signal is selected in output one;
One PWM control unit, be connected in described PWM/PFM automatic switching control circuit, described power switch driver element and described load, receive a load current signal of a voltage feedback signal of described load output, the output of described power switch driver element, and export an error signal to described PWM/PFM automatic switching control circuit, simultaneously, receive described selection signal, export a pwm control signal and give described power switch driver element; And
One PFM control unit, be connected in described PWM/PFM automatic switching control circuit, described power switch driver element and described load, receive a load current signal of a voltage feedback signal of described load output, the output of described power switch driver element, and export an electric current comparison signal to described PWM/PFM automatic switching control circuit, simultaneously, receive described selection signal, export a PFM control signal and give described power switch driver element.
2, the transducer with automatic switchover pulse duration/frequency modulating pattern according to claim 1 is characterized in that, the described error signal of described PWM control unit output is made comparisons computing and got by a described voltage feedback signal and a reference voltage.
3, the transducer with automatic switchover pulse duration/frequency modulating pattern according to claim 1 is characterized in that, the described electric current comparison signal of described PFM control unit output is made comparisons computing and got by a described load current signal and a reference current.
4, the transducer with automatic switchover pulse duration/frequency modulating pattern according to claim 1 is characterized in that, described PWM/PFM automatic switching control circuit includes:
One reference voltage generation unit is exported at least one reference voltage signal;
One PWM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described error signal, exports a PWM comparison signal;
One PWM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described error signal, exports a PFM comparison signal;
One first flip-flop is connected in described PWM comparing unit and described PFM comparing unit, and a reset signal is exported in computing;
One AND circuit, output one and gate signal; And
One second flip-flop is connected in described first flip-flop and described AND circuit, receives described reset signal and described and gate signal, and described selection signal is exported in computing.
5, the transducer with automatic switchover pulse duration/frequency modulating pattern according to claim 4, it is characterized in that, described AND circuit is connected in described PFM control unit and described second flip-flop, receive described electric current comparison signal and described selection signal, described electric current comparison signal and described selection signal are carried out and logical operation, export described and gate signal.
6, the transducer with automatic switchover pulse duration/frequency modulating pattern according to claim 4 is characterized in that, described first flip-flop is a R-S flip-flop.
7, the transducer with automatic switchover pulse duration/frequency modulating pattern according to claim 4 is characterized in that, described second flip-flop is a R-S flip-flop.
8, a kind of PWM/PFM automatic switching control circuit, receive a feedback signal of a PWM control unit and PFM control unit output, control by an activation control unit, output one selects signal to described PWM control unit and described PFM control unit, select switch control unit, it is characterized in that, include:
One reference voltage generation unit is exported at least one reference voltage signal;
One PWM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described feedback signal, exports a PWM comparison signal;
One PFM comparing unit is connected in described reference voltage generation unit, described activation control unit and described PWM control unit, receives described reference voltage signal, described activation enable signal and described feedback signal, exports a PFM comparison signal;
One first flip-flop is connected in described PWM comparing unit and described PFM comparing unit, and a reset signal is exported in computing;
One AND circuit, output one and gate signal; And
One second flip-flop is connected in described first flip-flop and described AND circuit, receives described reset signal and described and gate signal, and described selection signal is exported in computing.
9, PWM/PFM automatic switching control circuit according to claim 8, it is characterized in that, described AND circuit is connected in described PFM control unit and described second flip-flop, receive described feedback signal and described selection signal, feedback signal and described selection signal are carried out and (AND) logical operation, export described and gate signal.
10, PWM/PFM automatic switching control circuit according to claim 8 is characterized in that, described first flip-flop is a R-S flip-flop.
11, PWM/PFM automatic switching control circuit according to claim 8 is characterized in that, described second flip-flop is a R-S flip-flop.
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| Application Number | Priority Date | Filing Date | Title |
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| CN 200420066802 CN2720717Y (en) | 2004-06-08 | 2004-06-08 | Converter with automatic switching-over pulse width/frequency modulation mode |
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| CN 200420066802 CN2720717Y (en) | 2004-06-08 | 2004-06-08 | Converter with automatic switching-over pulse width/frequency modulation mode |
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| CN100377486C (en) * | 2004-06-08 | 2008-03-26 | 尼克森微电子股份有限公司 | Converter with automatic switching over pulse width/frequency modulating mode |
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| CN101790708B (en) * | 2007-08-28 | 2012-10-10 | 艾沃特有限公司 | Hybrid PWM and PFM current limit control |
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| CN100377486C (en) * | 2004-06-08 | 2008-03-26 | 尼克森微电子股份有限公司 | Converter with automatic switching over pulse width/frequency modulating mode |
| CN101034851B (en) * | 2005-10-28 | 2014-09-24 | 美国芯源系统股份有限公司 | Method and device for controlling switching regulators |
| CN101790708B (en) * | 2007-08-28 | 2012-10-10 | 艾沃特有限公司 | Hybrid PWM and PFM current limit control |
| CN101478236B (en) * | 2008-01-03 | 2010-12-08 | 天钰科技股份有限公司 | Voltage converter |
| CN101841238A (en) * | 2010-04-12 | 2010-09-22 | 无锡中星微电子有限公司 | Boost DC/DC converter and logic control circuit therein |
| CN101841238B (en) * | 2010-04-12 | 2012-11-21 | 无锡中星微电子有限公司 | Boost DC/DC converter and logic control circuit therein |
| CN102904503A (en) * | 2011-07-28 | 2013-01-30 | 北京中纺锐力机电有限公司 | Method and system for pulse width modulation control of switched reluctance machine |
| CN102904503B (en) * | 2011-07-28 | 2016-03-30 | 尼得科（北京）传动技术有限公司 | A kind of pulse width modulation control method of switched reluctance machines and system |
| CN104113215B (en) * | 2012-11-27 | 2017-03-22 | 台达电子工业股份有限公司 | DC-DC converter and control method thereof |
| CN104113215A (en) * | 2012-11-27 | 2014-10-22 | 台达电子工业股份有限公司 | DC-DC converter and control method thereof |
| CN104779799A (en) * | 2015-04-28 | 2015-07-15 | 矽力杰半导体技术(杭州)有限公司 | Control circuit, control method and flyback converter using same |
| CN105763063A (en) * | 2016-04-12 | 2016-07-13 | 金陵科技学院 | Single tube converter having RCD clamping function and control method therefor |
| CN109640714A (en) * | 2016-08-08 | 2019-04-16 | 莱战略控股公司 | Boost converter for aerosol delivery equipment |
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| CN113131737A (en) * | 2021-04-15 | 2021-07-16 | 东北大学 | PWM/PFM seamless switching controller suitable for switching power supply and control method thereof |
| CN113437870A (en) * | 2021-07-13 | 2021-09-24 | 上海艾为电子技术股份有限公司 | DC-DC converter, mode switching method and circuit thereof, and electronic device |
| CN113437870B (en) * | 2021-07-13 | 2023-09-22 | 上海艾为电子技术股份有限公司 | DC-DC converter, mode switching method and circuit thereof, and electronic device |
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