CN102751859B - Soft start circuit and start control method thereof - Google Patents
Soft start circuit and start control method thereof Download PDFInfo
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- CN102751859B CN102751859B CN201210240833.6A CN201210240833A CN102751859B CN 102751859 B CN102751859 B CN 102751859B CN 201210240833 A CN201210240833 A CN 201210240833A CN 102751859 B CN102751859 B CN 102751859B
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Abstract
The invention discloses a soft start circuit and a start control method thereof. The soft start circuit comprises a current source, an energy storage unit connected with the current source, a first switch unit connected between the current source and the energy storage unit, and a control unit connected with the first switch unit and is used for controlling the current source to periodically charge the energy storage unit. According to the soft start circuit and the start control method thereof, the problem that the cost of production of the soft start circuit in the prior art is high, and the effect that the cost of production of the soft start circuit is reduced is achieved.
Description
Technical field
The present invention relates to integrated circuit fields, in particular to a kind of soft starting circuit and startup control method thereof.
Background technology
In order to suppress the output voltage of the Circuits System such as voltage source, current source, LED drive circuit or motor drive circuit in start-up course or output current overshoot, usually in these Circuits System, soft starting circuit is applied, its principle comes the output voltage of control circuit system and the rate of climb of output current by the rate of climb of departure element reference voltage, prevents overshoot from damaging device.
Generally there are analog soft start and digital soft start two kinds of modes when controlling the rate of climb of error element reference voltage in prior art, wherein analog soft start device as shown in Figure 1a, analog soft start device is when starting, enable signal EN and reference voltage SS oscillogram are as shown in Figure 1 b, startup stage, reached the overshoot suppressing output voltage or output current by the reference voltage of departure adder.This device, usually can by reducing charging current I1 and increase charging capacitor C1 to realize in order to obtain enough start-up times.There is following drawback in this kind of device: charging current I1 is less, and precision is lower, and antijamming capability is more weak; Charging capacitor C1 is larger, and shared chip area is larger, and cost is higher.As shown in Figure 2 a, digital soft start device is when starting, and as shown in Figure 2 b, the device of this kind departure element reference voltage is in a digital manner by clock pulse control K for enable signal EN and reference voltage SS oscillogram for digital soft start device
1, K
2..., K
n, wherein K opened by N number of clock
n, the rate of climb of reference voltage SS can be controlled so accurately, but clock circuit and the cost spent by current source are almost equal to Fig. 1 a shown device, still there is the shortcoming that shared chip area is large, cost is high.
For the problem that soft starting circuit production cost in correlation technique is higher, at present effective solution is not yet proposed.
Summary of the invention
Main purpose of the present invention is provide a kind of soft starting circuit and start control method, to solve the problem that in prior art, soft starting circuit production cost is higher.
To achieve these goals, according to an aspect of the present invention, provide a kind of soft starting circuit, comprising: current source; Energy-storage units, is connected with current source; First switch element, is connected between current source and energy-storage units; And control unit, be connected with the first switch element, for controlling current source to energy-storage units periodically charging.
Further, control unit comprises: the first drive circuit, is connected with the first switch element, for generation of the first pulse drive signal of control first switch element break-make.
Further, the first pulse drive signal comprises the first high level signal and the first low level signal, and wherein, the conducting when receiving the first high level signal of the first switch element, ends when receiving the first low level signal; Or first switch element end when receiving the first high level signal, the conducting when receiving the first low level signal.
Further, control circuit also comprises: second switch unit, and first end is connected to first node, the second end ground connection, and wherein, first node is the node between energy-storage units and the first switch element.
Further, control unit also comprises: the second drive circuit, is connected with second switch unit, for generation of the second pulse drive signal controlling second switch unit break-make.
Further, the second pulse drive signal comprises the second high level signal and the second low level signal, and wherein, the conducting when receiving the second high level signal of second switch unit, ends when receiving the second low level signal; Or second switch unit ends when receiving the second high level signal, the conducting when receiving the second low level signal.
To achieve these goals, according to a further aspect in the invention, a kind of startup control method of soft starting circuit is provided, by controlling the energy-storage units periodicity charging of current source to soft starting circuit to make the voltage at energy-storage units two ends raise gradually.
Further, be connected with the first switch element between current source and energy-storage units, wherein, control current source comprises to the energy-storage units periodicity charging of soft starting circuit: send the first pulse drive signal to the first switch element to control the first switch element break-make.
Further, the first pulse drive signal comprises the first high level signal and the first low level signal, and wherein, the conducting when receiving the first high level signal of the first switch, ends when receiving the first low level signal; Or first switch end when receiving the first high level signal, the conducting when receiving the first low level signal.
Further, to the energy-storage units of soft starting circuit start control method and also comprise: energy-storage units is discharged periodically before charging at current source.
By the present invention, adopt the soft starting circuit comprising following structure: current source; Energy-storage units, is connected with current source; First switch element, is connected between current source and energy-storage units; And control unit, be connected with the first switch element, for controlling current source to energy-storage units periodically charging.By arranging the first switch element between current source and energy-storage units, and control the break-make realization control current source of the first switch element to energy-storage units periodically charging by control unit, the voltage realizing energy-storage units two ends to the charging of energy-storage units periodicity by controlling current source slowly raises, to reach the output voltage and output current overshoot that suppress the Circuits System of application soft starting circuit in start-up course, the effect that the output voltage of realizing circuit system and/or output current slowly raise, this kind of soft starting circuit only need arrange the first switch element between current source and energy-storage units, the integrated circuit area occupied of relative soft starting circuit and production cost, the area that the first switch element increased brings increases and cost drops into almost negligible, solve the problem that in prior art, soft starting circuit production cost is higher, and then reach the effect reducing soft starting circuit production cost.
Accompanying drawing explanation
The accompanying drawing forming a application's part is used to provide a further understanding of the present invention, and schematic description and description of the present invention, for explaining the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 a is the circuit diagram of the analog soft start circuit according to correlation technique;
Fig. 1 b is the drive singal of analog soft start circuit according to correlation technique and the schematic diagram of tank voltage;
Fig. 2 a is the circuit diagram of the digital soft start circuit according to correlation technique;
Fig. 2 b is the drive singal of digital soft start circuit according to correlation technique and the schematic diagram of tank voltage;
Fig. 3 a is the schematic diagram of the soft starting circuit according to the embodiment of the present invention;
Fig. 3 b is the oscillogram of the first drive singal of soft starting circuit according to the embodiment of the present invention; And
Fig. 3 c is the oscillogram of the second drive singal according to the soft starting circuit of the embodiment of the present invention and tank voltage.
Embodiment
It should be noted that, when not conflicting, the embodiment in the application and the feature in embodiment can combine mutually.Below with reference to the accompanying drawings and describe the present invention in detail in conjunction with the embodiments.
Embodiments provide a kind of soft starting circuit, below the soft starting circuit that the embodiment of the present invention provides be specifically introduced:
Fig. 3 a is the circuit diagram of the soft starting circuit according to the embodiment of the present invention, and as shown in Figure 3 a, the soft starting circuit of the embodiment of the present invention comprises current source, energy-storage units, the first switch element K1 and control unit (not shown).Wherein, first switch element K1 is connected between current source and energy-storage units, to realize disconnection or the conducting of charge circuit, control unit is connected with the first switch element K1, for sending drive control signal to the first switch element K1, realize control first switch element K1 periodically adhesive or open, to realize controlling current source to energy-storage units periodically charging.
The soft starting circuit of the embodiment of the present invention by arranging the first switch element between current source and energy-storage units, and control the break-make realization control current source of the first switch element to energy-storage units periodically charging by control unit, the voltage realizing energy-storage units two ends to the charging of energy-storage units periodicity by controlling current source slowly raises, to reach the output voltage and the output current overshoot that suppress to apply the Circuits System of soft starting circuit in soft start-up process, the effect that the output voltage of realizing circuit system and/or output current slowly raise, this kind of soft starting circuit only need arrange the first switch element between current source and energy-storage units, the integrated circuit area occupied of relative soft starting circuit and production cost, the area that the first switch element increased brings increases and cost drops into almost negligible, solve the problem that in prior art, soft starting circuit production cost is higher, and then reach the effect reducing soft starting circuit production cost.
Particularly, control unit comprises the first drive circuit be connected with the first switch element K1, this first drive circuit is for generation of the first pulse drive signal Vclk of control first switch element K1 break-make, wherein, first pulse drive signal can be low and high level signal, first switch element K1 can the conducting when receiving high level signal, correspondingly ends when receiving low level signal; Or the first switch element K1 can end when receiving high level signal, the correspondingly conducting when receiving low level signal.With first switch element K1 conducting when receiving high level signal, when receiving low level signal, cut-off is illustrated the soft start principle of soft starting circuit, the oscillogram of the first drive pulse signal as shown in Figure 3 b, when the drive pulse signal of control first switch element K1 becomes high level, K1 conducting, now current source I1 is to energy-storage units (energy-storage units can be can charge and discharge capacitance C1) charging, then, in each pulse period, current source makes the voltage at C1 two ends raise to C1 charging
wherein, t
dbe that in the first pulse drive signal one-period T, high level signal is held time.When the first switch element K1 receives low level signal, K1 ends, and now I1 stops to C1 charging, and C1 keeps current voltage until next high level signal pulse arrives.If the reference voltage of output is raised to Vss, then the whole soft-start time T of soft starting circuit after definition soft start completes
ssfor:
Define the duty ratio of the first drive pulse signal
substitution formula 1.1:
Can be found out by formula 1.2 if reduce K, namely reduce the duty ratio of pulse signal, the speed of the soft start that can slow down.In other words, under the prerequisite that soft start speed is certain, the charging current I1 of current source can be increased by reducing duty ratio K value, realizing the precision and the antijamming capability that improve soft start, can reduce C1 by reducing duty ratio K value, the cost realizing reducing soft starting circuit drops into simultaneously.
Preferably, soft starting circuit also comprises the second switch unit K2 be connected between signal ground and first node.Wherein, first node is the node between energy-storage units C1 and the first switch element K1.The two ends of second switch unit K2 are connected to the two ends of energy-storage units C1 to realize the energy in energy-storage units C1 whether to discharge, wherein, when the K2 conducting of second switch unit, signal ground is directly accessed in the two ends of energy-storage units C1, realize discharging the energy in energy-storage units C1, when second switch unit K2 opens, energy-storage units C1 stops releasing energy.Wherein, second switch unit K2 conducting can being controlled at current source before energy-storage units charging, make to carry out initialization to energy-storage units C1, then when starting to charge to energy-storage units, opening second switch unit K2.Particularly, the signal controlling second switch unit K2 conducting or cut-off can be produced by the second drive circuit in control unit, second drive circuit is connected with second switch unit K2, the K2 conducting of second switch unit or cut-off is controlled to second switch unit K2 by sending the second drive pulse signal EN, wherein, second pulse drive signal EN can be high level for the starting stage, maintenance stage is low level signal, also can be low level for the starting stage, maintenance stage is the signal of high level, namely, the conducting when receiving high level signal of second switch unit can be controlled, end when receiving low level signal, or control second switch unit ends when receiving high level signal, the conducting when receiving low level signal.For the second pulse drive signal EN starting stage be low level signal, the maintenance stage illustrates the soft start principle of soft starting circuit for high level signal, the oscillogram of the voltage at the second drive pulse signal and energy-storage units two ends as shown in Figure 3 c, when the second pulse drive signal EN is low level signal, second switch unit K2 conducting, carries out discharge process to energy-storage units C1; When the second pulse drive signal EN becomes high level signal, control unit also controls the first switch element K1 conducting, now, current source starts to carry out periodicity charging to energy-storage units under the conducting or cut-off of K1 switch, and the voltage SS realizing energy-storage units two ends slowly raises.
By arranging second switch unit in soft starting circuit, achieving and before energy-storage units charging, initialization being carried out to energy-storage units at current source, avoid energy-storage units due to reset condition and just store the voltage and/or current over pulse that higher electricity causes.
Further, the embodiment of the present invention additionally provides a kind of startup control method of soft starting circuit, the soft starting circuit that this startup control method can be provided by embodiment of the present invention foregoing performs, and is specifically introduced below to the startup control method that the embodiment of the present invention provides:
When soft starting circuit soft start, by controlling the energy-storage units periodicity charging of current source to soft starting circuit to make the voltage at energy-storage units two ends raise gradually.Wherein, the break-make mainly through controlling the charge circuit between current source and energy-storage units realizes charging to the periodicity of energy-storage units.Particularly, the first switch element is set between current source and energy-storage units, by sending the first pulse drive signal to the first switch element to control the break-make that the first switch element break-make realizes charge circuit.
The voltage that the startup control method of the embodiment of the present invention realizes energy-storage units two ends by control current source to the charging of energy-storage units periodicity slowly raises, to reach the output voltage and output current overshoot that suppress the Circuits System of application soft starting circuit in start-up course, the soft start effect of realizing circuit system, this kind of soft starting circuit only need arrange the first switch element between current source and energy-storage units, the integrated circuit area occupied of relative soft starting circuit and production cost, the area that the first switch element increased brings increases and cost drops into almost negligible, solve the problem that in prior art, soft starting circuit production cost is higher, and then reach the effect reducing soft starting circuit production cost.
Further, at current source to the energy-storage units of soft starting circuit periodically before charging, the startup control method of the embodiment of the present invention also comprises: discharge to energy-storage units.
By discharging to energy-storage units, achieving and before energy-storage units charging, initialization being carried out to energy-storage units at current source, avoid energy-storage units due to reset condition and just store the voltage and/or current over pulse that higher electricity causes.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (7)
1. a soft starting circuit, is characterized in that, comprising:
Current source;
Energy-storage units, is connected with described current source;
First switch element, is connected between described current source and described energy-storage units; And
Control unit, be connected with described first switch element, for controlling described current source to the periodically charging of described energy-storage units, wherein, described control unit comprises the first drive circuit, be connected with described first switch element, for generation of the first pulse drive signal controlling described first switch element break-make; Described control circuit also comprises: second switch unit, first end is connected to first node, second end ground connection, wherein, described first node is the node between described energy-storage units and described first switch element, and the two ends of described second switch unit are connected to the two ends of energy-storage units to realize the energy in energy-storage units whether to discharge, wherein, before described current source periodically charges to described energy-storage units, by described second switch unit, described energy-storage units is discharged.
2. soft starting circuit according to claim 1, is characterized in that, described first pulse drive signal comprises the first high level signal and the first low level signal, wherein,
The conducting when receiving described first high level signal of described first switch element, ends when receiving described first low level signal; Or
Described first switch element ends when receiving described first high level signal, the conducting when receiving described first low level signal.
3. soft starting circuit according to claim 1, is characterized in that, described control unit also comprises:
Second drive circuit, is connected with described second switch unit, for generation of the second pulse drive signal controlling described second switch unit break-make.
4. soft starting circuit according to claim 3, is characterized in that, described second pulse drive signal comprises the second high level signal and the second low level signal, wherein,
The conducting when receiving described second high level signal of described second switch unit, ends when receiving described second low level signal; Or
Described second switch unit ends when receiving described second high level signal, the conducting when receiving described second low level signal.
5. use a startup control method for the soft starting circuit any one of claim 1 to 4, it is characterized in that, by controlling the energy-storage units periodicity charging of current source to soft starting circuit to make the voltage at described energy-storage units two ends raise gradually,
Wherein, be connected with the first switch element between described current source and described energy-storage units, control current source comprises to the energy-storage units periodicity charging of soft starting circuit:
Send the first pulse drive signal to described first switch element to control described first switch element break-make.
6. startup control method according to claim 5, is characterized in that, described first pulse drive signal comprises the first high level signal and the first low level signal, wherein,
The conducting when receiving described first high level signal of described first switch, ends when receiving described first low level signal; Or
Described first switch ends when receiving described first high level signal, the conducting when receiving described first low level signal.
7. startup control method according to claim 5, is characterized in that, at described current source to the energy-storage units of soft starting circuit periodically before charging, described startup control method also comprises:
Described energy-storage units is discharged.
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| CN103904875A (en) * | 2014-03-24 | 2014-07-02 | 合肥工业大学 | Digital soft start circuit in switching power source |
| EP3481556B1 (en) * | 2016-08-31 | 2020-07-08 | Selfrag AG | Method for operating a high-voltage pulse system |
| CN111293859B (en) * | 2018-12-10 | 2021-10-12 | 圣邦微电子（北京）股份有限公司 | Driving circuit and driving method of power switch tube |
| CN110492440B (en) * | 2019-07-24 | 2022-04-12 | 上海空间电源研究所 | Soft start protection circuit for high-power topology control |
| CN112398326B (en) * | 2019-08-13 | 2022-04-05 | 国民技术股份有限公司 | Soft start device and method based on multi-output device, power supply and chip |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202737836U (en) * | 2012-07-11 | 2013-02-13 | 圣邦微电子（北京）股份有限公司 | Soft start circuit |
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| WO2006102929A1 (en) * | 2005-04-01 | 2006-10-05 | Freescale Semiconductor, Inc. | Dc-dc converter soft start circuit using duty cycle limiting |
| CN101340142B (en) * | 2008-08-15 | 2010-10-27 | 华为技术有限公司 | Method, apparatus and system for soft startup of electric power |
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| CN202737836U (en) * | 2012-07-11 | 2013-02-13 | 圣邦微电子（北京）股份有限公司 | Soft start circuit |
Non-Patent Citations (1)
| Title |
|---|
| 张艳红等.升压式DC/DC的软启动电路的设计.《华侨大学学报(自然科学版)》.2009,第30卷(第6期),第632-636页. * |
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