CN103532376B - power charge pump - Google Patents
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- CN103532376B CN103532376B CN201310518255.2A CN201310518255A CN103532376B CN 103532376 B CN103532376 B CN 103532376B CN 201310518255 A CN201310518255 A CN 201310518255A CN 103532376 B CN103532376 B CN 103532376B
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- 238000005516 engineering process Methods 0.000 description 5
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Abstract
Embodiment of the present invention first aspect provides a kind of power charge pump, described power charge pump includes output capacitance, at least one flies electric capacity, the first voltage source and the second voltage source and first group of clock switch and second group of clock switch, the first, second each self-contained at least two clock switch of clock switch, the ON time of first group of clock switch and second group of clock switch is the most overlapping；During first group of clock switch conducting, control at least one flies electric capacity and produces the first voltage of the first voltage source and the tertiary voltage of the second difference in voltage of the second voltage source；During second group of clock switch conducting, control output capacitance and produce the output voltage proportional to tertiary voltage.The power charge pump provided by the embodiment of the present invention, can build the voltage mode of the more input voltage of more generation/output voltage multiplying power, contributes to optimizing the power charge efficiency of pump.
Description
Technical field
The present invention relates to electronic applications, be specifically related to a kind of power charge pump.
Background technology
Charge pump circuit based on switching capacity is widely used in voltage conversion circuit, it is possible to achieve relatively
High voltage conversion efficiency.Power charge pump of the prior art, one input voltage of general employing, produces
The raw output voltage higher than input or the output voltage lower than output, its efficiency is higher than linear voltage regulator.
Comparing DC-to-DC converter based on inductance to compare, power charge pump is without the bigger electricity of volume
Sense, it is more suitable for the application that PCB space is less, and cost is relatively low.For preferably switch,
Its energy loss can be left in the basket, in such a case, it is possible to think that the efficiency of power charge pump circuit is
100%.But when power charge pump circuit can only change voltage with some fixing multiplying power, its ideal power is
100%.But such fixed multiplying power is a limited number of kind.In prior art, for flying only with two
In the application of electric capacity (flying capacitor), for same input voltage source, the VO/VIN that can produce
The multiplying power of (wherein VO is output voltage, and VIN is input voltage) has: 3 times, 2 times, 3/2 times,
4/3 times, 1 times, 2/3 times, 1/2 times, 1/3 times.For flying electric capacity (flying capacitor) only with one
Applying, present in prior art, VO/VIN multiplying power has: 2 times, 1 times, 1/2 times.
Use the mode increasing the number flying electric capacity, more possible multiplying power can be produced, but cost is therewith
Increase.Increase more possible multiplying power, be conducive to optimizing the real work efficiency of power charge pump.Such as,
Input voltage is 3.3V, and output voltage desired value is 1.7V, flies electric capacity situation for only one, can only adopt
By 1 times of pattern, producing 3.3V voltage, then by linear voltage regulation technology, (linear voltage regulation technology can only reduce
Voltage) reduce to 1.7V, its efficiency ideally is 1.7V/3.3V=51.5%.Fly for using two
Electric capacity situation, then can use 2/3 times of pattern, produces 2.2V voltage, then by linear voltage regulation technology
Reducing to 1.7V, its efficiency ideally is 1.7V/2.2V=77.3%, this improves efficiency.When
When input voltage changes within the specific limits (when such as battery is powered, along with battery discharge or charging, its
Voltage can be continually changing), more multiplying power patterns contribute to optimizing the work efficiency under different input voltage.
Fly electric capacity the most, help the more multiplying power patterns of generation, but cost is higher.Electric capacity is flown as the most less,
Produce more possible multiplying power, be problem demanding prompt solution of the present invention.
Summary of the invention
It is an object of the invention to provide a kind of power charge pump, to improve the profit flying electric capacity in power charge pump
Use efficiency.
For achieving the above object, embodiment of the present invention first aspect provides a kind of power charge pump, described
Power charge pump include an output capacitance, at least one fly electric capacity, the first voltage source and the second voltage source,
And first group of clock switch and second group of clock switch, described first, second clock switch each wraps
Containing at least two clock switch, described first group of clock switch and the ON time of second group of clock switch
The most overlapping；
During described first group of clock switch conducting, described in control, at least one flies described first electricity of electric capacity generation
First voltage of potential source and the tertiary voltage of the second difference in voltage of the second voltage source；
During described second group of clock switch conducting, control described output capacitance and produce to become to compare with tertiary voltage
The output voltage of example.
Based on first aspect, in the embodiment that the first is possible, described power charge pump comprises one
The individual electric capacity that flies, described first group of clock switch includes the first clock switch and second clock switch, described
Second group of clock switch includes the 3rd clock switch and the 4th clock switch.
The first possible embodiment based on first aspect, in the embodiment that the second is possible,
Described first clock switch connects positive pole and described the first end flying electric capacity, the institute of described first voltage source
State the second end and the positive pole of described second voltage source flying electric capacity described in second clock switch connection, described
3rd clock switch flies the first paragraph of electric capacity and the first end of described output capacitance described in connecting, and described the
Four clock switch fly the second end of electric capacity, the second end of described output capacitance and described the described in connecting
One, the negative pole of the second voltage source.
Based on first aspect, in the embodiment that the third is possible, described power charge pump comprises
One flies electric capacity and second flies electric capacity, and described first group of clock switch includes the first clock switch, second clock
Switch and the 5th clock switch, described second group of clock switch includes that the 3rd clock switch, the 4th clock are opened
Pass, the 6th clock switch and the 7th clock switch.
The third possible embodiment based on first aspect, in the 4th kind of possible embodiment,
The positive pole and described first that described first clock switch connects described first voltage source flies the first end of electric capacity,
Described second clock switch connects described second and is just flying the second end of electric capacity and described second voltage source
Pole, described 3rd clock switch connects described first and flies the of the first end of electric capacity and described output capacitance
One end, described 4th clock switch connects described second and flies the second end of electric capacity, described output capacitance
Second end and the negative pole of described first, second voltage source, described 5th clock switch connects described the
One the second end flying electric capacity and described second flies the first end of electric capacity, and described 6th clock switch connects institute
State first and fly the second end of electric capacity, the second end of described output capacitance and described first, second voltage
The negative pole in source；Described 7th clock switch connects the described second the first end flying electric capacity and described output electricity
The first end held.
Based on any one above possible embodiment, described first voltage source is battery, described
Second voltage source is the DC-to-DC converter in circuit or linear voltage regulator.
Based on any one above possible embodiment, described first group of clock is by clock when first
System, when the first clock is high level, described first group of clock conducting；Described second group of clock is by
Two clock controls, when second clock is high level, described second group of clock conducting.
Based on any one above possible embodiment, the ON time of described first group of clock and
Very first time length it is spaced between the ON time of described second group of clock.
The power charge pump provided by the embodiment of the present invention, it is possible to use present in application system other
Voltage, design power electric charge pump, then by utilizing other voltages in addition to cell voltage as the second voltage
Source, builds the voltage mode of the more input voltage of more generation/output voltage multiplying power, contributes to optimizing power
The electric charge efficiency of pump.
Accompanying drawing explanation
For the technical scheme being illustrated more clearly that in the embodiment of the present invention, below will be to embodiment or existing
In having technology to describe, the required accompanying drawing used is briefly described, it should be apparent that, in describing below
Accompanying drawing be only some embodiments of the present invention, for those of ordinary skill in the art, not
On the premise of paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.
Fig. 1 is the circuit theory diagrams of a kind of embodiment of a kind of power charge pump that the embodiment of the present invention provides；
Fig. 2 is the first working state figure of the embodiment shown in Fig. 1；
Fig. 3 is the second working state figure of the embodiment shown in Fig. 1；
Fig. 4 is the circuit theory diagrams of the another kind of power charge pump that the embodiment of the present invention provides；
Fig. 5 is the first working state figure of the embodiment shown in Fig. 4；
Fig. 6 is the second working state figure of the embodiment shown in Fig. 4.
Detailed description of the invention
Below by drawings and Examples, technical scheme is described in further detail.
The core concept of the embodiment of the present invention is, utilizes other voltages more present in system, the most flat
The systems such as plate computer, smart mobile phone, bluetooth earphone are all equipped with Power Management Unit (Power Management
Units), they generally can support that plurality of voltages exports, and some is linear voltage regulator, some be direct current-
Direct current transducer, by these as the second input voltage source and battery as the first voltage source, design merit
Rate electric charge pump, builds the voltage mode of other multiplying powers more, to optimize the power charge efficiency of pump.
Embodiments providing a kind of power charge pump, described power charge pump includes an output electricity
Hold, at least one fly electric capacity, the first voltage source and the second voltage source and first group of clock switch and the
Two groups of clock switch, the described first, second each self-contained at least two clock switch of clock switch, institute
The ON time stating first group of clock switch and second group of clock switch is the most overlapping；Described first group of clock
During switch conduction, described in control, at least one flies electric capacity and produces first voltage and the of described first voltage source
The tertiary voltage of the second difference in voltage of two voltage sources；During described second group of clock switch conducting, control
Described output capacitance produces the output voltage proportional to tertiary voltage.
Wherein, described first group of clock is controlled by the first clock CK1, when CK1 is high level,
Described first group of clock conducting；Described second group of clock is by CK2 control, when CK2 is high level,
Described second group of clock conducting.The ON time of described first group of clock and leading of described second group of clock
It is spaced very first time length between the logical time.
As it is shown in figure 1, in one embodiment, described power charge pump comprises one and flies electric capacity C1,
Described first group of clock switch include the first clock switch S1 and second clock switch S2, described second
Group clock switch includes the 3rd clock switch S3 and the 4th clock switch S4.
Described S1 connects the positive pole of described first voltage source V1 and described the first end flying electric capacity C1,
Described S2 connects the second end and the positive pole of described second voltage source V2 of described C1, and described S3 connects
First end of described C1 and described output capacitance COThe first end, described S4 connects the of described C1
Two ends, described COThe second end and the negative pole of voltage source V1 and V2.
Wherein, the battery that the first voltage source V1 is usually in circuit, the second voltage source can be circuit
In linear voltage regulator or the voltage follower circuit such as DC-to-DC converter.
As shown in Figures 2 and 3, Fig. 2～Fig. 3 describes the specific works process of Fig. 1 embodiment.When
When CK1 is high level, corresponding diagram 2 duty, switch S1 and S2 conducting, switch S3 and S4 breaks
Open.Burning voltage on electric capacity meets VC1+ V2=V1, i.e. VC1=V1-V2, wherein VC1For flying electric capacity
The voltage at C1 two ends, V1 is the magnitude of voltage of voltage source V1, and V2 is the magnitude of voltage of voltage source V2.Wherein,
CK1 Yu CK2 is inverting clock signal, between cannot there is not overlappingly control, i.e. turn off at switch S1 and S2
After, postponing certain Dead Time, switch S3 and S4 just turns on；After switch S3 and S4 is also off,
Postponing certain Dead Time, switch S1 and S2 just turns on.
When CK2 is high level, corresponding diagram 3 duty, switch S1 and S2 disconnects, and switchs S3
Turn on S4.The burning voltage flown on electric capacity meets VC1=VO, wherein VC1For electric capacity C1 two ends
Voltage, VOVoltage for output capacitance Co two ends.
Owing to, under steady-working state, electric capacity both end voltage remains equal, then VC1=VO=V1-V2, when
If so the position of V1 and V2 in crossing-over map 1, then can realize VO=V2-V1.
Fig. 1 describe embodiment only one fly electric capacity (flying capacitor) situation, generation can be built
The voltage output of V1-V2.If V1=3.3V, output target voltage values is 1.7V, flies electric capacity to two
Situation, the optimum efficiency pattern using prior art is 2/3 times of pattern, and ideal efficiency is
1.7V/2.2V=77.3%；And fly electric capacity situation only with one, use the optimum efficiency pattern of prior art
Being 1 times of pattern, ideal efficiency is 1.7V/3.3V=51.5%.And use the present invention, if V1=3.3V,
V2=1.5V, then ideal efficiency is 1.7V/ (3.3V-1.5V)=94.4%, and only flies electric capacity, significantly with one
Improve circuit utilization ratio.
As shown in Figure 4, in another kind is example, described power charge pump comprises first and flies electric capacity C1
Flying electric capacity C2 with second, described first group of clock switch includes that the first clock switch S1, second clock switch
S2 and the 5th clock switch S5, described second group of clock switch include the 3rd clock switch S3, the 4th time
Clock switch S4, the 6th clock switch S6 and the 7th clock switch S7.
Described S1 connects positive pole and first end of described C1 of described first voltage source V1, and described S2 is even
Connecing the second end and the positive pole of described second voltage source V2 of described C2, described S3 connects described C1
The first end and described COThe first end, described S4 connects second end of described C2, described CO's
Second end and the negative pole of described voltage source V1, V2, described S5 connect described C1 the second end and
First end of described C2, described S6 connects second end of described C1, described COThe second end and
The negative pole of described voltage source V1, V2；Described S7 connects first end of described C2 and described CO's
First end.
Similar with the embodiment shown in Fig. 1, that the first voltage source V1 is usually in circuit battery, the
Two voltage sources can be the voltage follower circuits such as the linear voltage regulator in circuit or DC-to-DC converter.
Fig. 5～Fig. 6 describes the specific works process of Fig. 4 embodiment, when CK1 is high level, as
Shown in Fig. 5, switch S1, S2, S5 conducting, switch S3, S4, S6, S7 disconnect.Capacitance voltage is full
Foot:
VC1+VC2+V2=V1 (1)
Wherein VC1For the voltage at electric capacity C1 two ends, VC2For the voltage at electric capacity C2 two ends, V1 is voltage
The magnitude of voltage of source V1, V2 is the magnitude of voltage of voltage source V2.
When CK2 is high level, as shown in Figure 6, switch S1, S2, S5 disconnect, switch S3, S4,
S6, S7 turn on.Capacitance voltage meets:
VC1=VC2=VO (2)
Wherein, VC1For the voltage at electric capacity C1 two ends, VC2For the voltage at electric capacity C2 two ends, VOFor defeated
Go out the magnitude of voltage at electric capacity two ends.
Under steady statue, the voltage at electric capacity two ends is equal.Understand according to formula (1) and (2):
VO=(V1-V2)/2
The second embodiment described by Fig. 4, is used two and flies electric capacity C1 and C2.Can produce
Output voltage is equal to (V1-V2)/2.
The power charge pump provided by the embodiment of the present invention, it is possible to use present in application system other
Voltage, design power electric charge pump, then by utilizing other voltages in addition to cell voltage as the second voltage
Source, builds the voltage mode of the more input voltage of more generation/output voltage multiplying power, contributes to optimizing power
The electric charge efficiency of pump.
It is understood that can also core concept according to embodiments of the present invention, more by design
Clock switch and fly electric capacity, to produce the output voltage of more multiplying power, seldom repeats at this.
Above-described detailed description of the invention, is carried out the purpose of the present invention, technical scheme and beneficial effect
Further describe, be it should be understood that the foregoing is only the present invention detailed description of the invention and
, the protection domain being not intended to limit the present invention, all within the spirit and principles in the present invention, done
Any modification, equivalent substitution and improvement etc., should be included within the scope of the present invention.
Claims (4)
1. a power charge pump, it is characterised in that include an output capacitance, at least one fly electric capacity,
First voltage source and the second voltage source and first group of clock switch and second group of clock switch, described
First, second group of each self-contained at least two clock switch of clock switch, described first group of clock switch
The most overlapping with the ON time of second group of clock switch；
During described first group of clock switch conducting, described in control, at least one flies described first electricity of electric capacity generation
First voltage of potential source and the tertiary voltage of the second difference in voltage of the second voltage source；
During described second group of clock switch conducting, control described output capacitance and produce to become to compare with tertiary voltage
The output voltage of example；Wherein,
Described at least one flies electric capacity comprises first and flies electric capacity and second and fly electric capacity, described first group of clock switch
Including the first clock switch, second clock switch and the 5th clock switch, described second group of clock switch bag
Include the 3rd clock switch, the 4th clock switch, the 6th clock switch and the 7th clock switch；
Described first clock switch is connected to the positive pole and described first of described first voltage source and flies the of electric capacity
Between one end, described second clock switch is connected to the described second the second end flying electric capacity and described second
Between the positive pole of voltage source, described 3rd clock switch be connected to described first fly electric capacity the first end and
Between first end of described output capacitance, described 4th clock switch is connected to described second and flies electric capacity
Between second end and the second end of described output capacitance, and described 4th clock switch and described output
The junction point of the second end of electric capacity is connected, when the described 5th with the negative pole of described first, second voltage source
Clock switch is connected between the first end that the described first the second end flying electric capacity and described second flies electric capacity,
Described 6th clock switch is connected to the described first the second end flying electric capacity and the second of described output capacitance
Between end, and the junction point of the second end of described 6th clock switch and described output capacitance is with described
The negative pole of first, second voltage source is connected；Described 7th clock switch connects described second and flies electric capacity
First end and the first end of described output capacitance.
2. the power charge pump as described in any one of claim 1, it is characterised in that described first electricity
Potential source is battery, and described second voltage source is the DC-to-DC converter in circuit or linear voltage regulator.
3. the power charge pump as described in any one of claim 1 to 2, it is characterised in that described
One group of clock switch is by the first clock control, when the first clock is high level, and described first group of clock
Switch conduction；Described second group of clock switch is by second clock control, when second clock is high level,
Described second group of clock switch conducting.
4. power charge pump as claimed in claim 3, it is characterised in that described first group of clock is opened
Very first time length it is spaced between the ON time and the ON time of described second group of clock switch that close.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310518255.2A CN103532376B (en) | 2013-10-28 | power charge pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310518255.2A CN103532376B (en) | 2013-10-28 | power charge pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103532376A CN103532376A (en) | 2014-01-22 |
| CN103532376B true CN103532376B (en) | 2016-11-30 |
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| CN101647181A (en) * | 2006-12-30 | 2010-02-10 | 先进模拟科技公司 | The efficient DC/DC electric pressure converter that comprises the rearmounted transducer of down inductive switch preregulator and capacitance-type switch |
| US7786712B2 (en) * | 2006-12-30 | 2010-08-31 | Advanced Analogic Technologies, Inc. | High-efficiency DC/DC voltage converter including up inductive switching pre-regulator and capacitive switching post-converter |
| CN102171918A (en) * | 2008-07-31 | 2011-08-31 | 先进模拟科技公司 | Step-up DC/DC voltage converter with improved transient current capability |
| CN103607115A (en) * | 2013-09-25 | 2014-02-26 | 无锡中星微电子有限公司 | Charge pump device |
| CN203537232U (en) * | 2013-09-25 | 2014-04-09 | 无锡中星微电子有限公司 | Charge pump device |
| CN203590027U (en) * | 2013-10-28 | 2014-05-07 | 无锡中星微电子有限公司 | Power charge pump |
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1667688A (en) * | 2004-03-12 | 2005-09-14 | 精工爱普生株式会社 | Power supply circuit, driver IC using the power supply circuit, liquid crystal display device, and electronic instrument |
| CN101083431A (en) * | 2006-05-29 | 2007-12-05 | 松下电器产业株式会社 | Charge pump circuit |
| CN101647181A (en) * | 2006-12-30 | 2010-02-10 | 先进模拟科技公司 | The efficient DC/DC electric pressure converter that comprises the rearmounted transducer of down inductive switch preregulator and capacitance-type switch |
| US7786712B2 (en) * | 2006-12-30 | 2010-08-31 | Advanced Analogic Technologies, Inc. | High-efficiency DC/DC voltage converter including up inductive switching pre-regulator and capacitive switching post-converter |
| CN102171918A (en) * | 2008-07-31 | 2011-08-31 | 先进模拟科技公司 | Step-up DC/DC voltage converter with improved transient current capability |
| CN103607115A (en) * | 2013-09-25 | 2014-02-26 | 无锡中星微电子有限公司 | Charge pump device |
| CN203537232U (en) * | 2013-09-25 | 2014-04-09 | 无锡中星微电子有限公司 | Charge pump device |
| CN203590027U (en) * | 2013-10-28 | 2014-05-07 | 无锡中星微电子有限公司 | Power charge pump |
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Address after: Wuxi District of Jiangsu city of Wuxi province Qingyuan Road 214135 No. 18 Taihu International Science Park sensor network university science and Technology Park 530 building A1001 Applicant after: WUXI ZHONGGAN MICROELECTRONIC CO., LTD. Address before: A 530 building 214135 Jiangsu Province, Wuxi city Wuxi District Taihu international science and Technology Park Qingyuan Road 10 Applicant before: Wuxi Vimicro Co., Ltd. |
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