CN203813665U - Low-noise step-down switching voltage regulator with programmable voltage conversion rate limiter - Google Patents
Low-noise step-down switching voltage regulator with programmable voltage conversion rate limiter Download PDFInfo
- Publication number
- CN203813665U CN203813665U CN201320761208.6U CN201320761208U CN203813665U CN 203813665 U CN203813665 U CN 203813665U CN 201320761208 U CN201320761208 U CN 201320761208U CN 203813665 U CN203813665 U CN 203813665U
- Authority
- CN
- China
- Prior art keywords
- transistor
- switching
- terminal
- voltage
- rate
- 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.)
- Expired - Lifetime
Links
- 238000006243 chemical reaction Methods 0.000 title claims abstract description 11
- 238000000034 method Methods 0.000 claims abstract description 5
- 230000008878 coupling Effects 0.000 claims description 32
- 238000010168 coupling process Methods 0.000 claims description 32
- 238000005859 coupling reaction Methods 0.000 claims description 32
- 239000003990 capacitor Substances 0.000 claims description 25
- 230000007704 transition Effects 0.000 claims description 23
- 230000008859 change Effects 0.000 claims description 17
- 230000001939 inductive effect Effects 0.000 description 15
- 238000010586 diagram Methods 0.000 description 7
- 239000003381 stabilizer Substances 0.000 description 5
- 230000033228 biological regulation Effects 0.000 description 4
- 229920006395 saturated elastomer Polymers 0.000 description 4
- 208000001953 Hypotension Diseases 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000036543 hypotension Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- WLRMANUAADYWEA-NWASOUNVSA-N (S)-timolol maleate Chemical compound OC(=O)\C=C/C(O)=O.CC(C)(C)NC[C@H](O)COC1=NSN=C1N1CCOCC1 WLRMANUAADYWEA-NWASOUNVSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a low-noise step-down switching voltage regulator with a programmable voltage conversion rate limiter, and provides a low-noise step-down switching voltage regulator with the programmable voltage conversion rate limiter and an application method. The circuit comprises a voltage and current conversion rate limiting circuit. The utility model describes the accomplishing of the control of a current mode and a voltage module, and provides the effective low-noise step-down switching voltage regulator circuit.
Description
Technical field:
The present invention relates to a kind of switching regulator circuit.More particularly, the present invention relates to decompression DC to direct current (DC is to DC) Switching Converter Topologies (being also referred to as " step-down switching regulator "), known step-down switching regulator before comparing, provides low noise and programmable restriction to press the function of switching rate.
Background technology:
Fig. 1 has illustrated a known step-down switching regulator, for example, provides a predetermined constant output voltage V from not limited positive voltage input voltage (, battery)
outbe used for driving a load R
lalthough, just as a resistance, can be also a portable communication device or computer.Step-down switching regulator 10 comprises controlled current source 12, transistor 14 and 16, diode 18, inductance 20, capacitor 22, and control circuit 24.Control circuit 24 produces control signal V
r, open and close in desired frequency range control, conventionally in 100-300 KHz.
The operation of step-down switching regulator 10 is as follows: in the beginning of a switch periods, and the V of control signal
ruprise, make controlled current source 12 electric current I that leads
1, and make transistor 14 conductings.The base stage of the collector electrode driving transistors 16 of transistor 14, makes transistor 16 conductings.Once transistor 16 conductings, the emitter current of transistor 16 just increases sharply with higher forward current transfer ratio.Along with the revolution of electric current, at inductance input node V
sWvoltage is just with a high about V of positive voltage switching rate
iNincrease sharply.Diode 18 ends, a V
iN-V
oUTvoltage V
lbe added on inductor 20, switching voltage pulse transition is become to inductive current I
l.Inductor 20 and capacitor 22 form a low pass filter eliminates the output voltage V of switching frequency and harmonic component thereof
oUT.
Control circuit 24 monitors output voltage V
oUTand provide control signal, by changing regulation output voltage V switching time of transistor 16
r(changing the duty ratio of step-down switching regulator, is the time of opening in one-period to account for the percentage in cycle).Especially, work as V
rbe low level, controlled current source 12 is closed, and makes transistor 14 and 16 cut-offs.Because transistor 16 ends, the input node voltage V of inductance
sWbe dropped rapidly to and be similar to earth potential with a high negative voltage transition speed.Along with voltage revolution, transistorized 16 emitter current declines rapidly with a higher negative current transfer ratio.In addition V,
lbecome-V
oUT, diode 18 conductings, and produced inductive current I
l, and inductance input node V
sWremain on and be approximately earth potential, until the control signal of next cycle.
Therefore, in each switch periods, inductance input node V
sWswitch is about V
iNand between ground.Also have and in switch transition process, obtain overall efficiency and maximize in order to reduce the heating certainly of instantaneous power loss and transistor 16, positive and negative electric current and transistor 16 voltage conversioning rates are higher.But transfer ratio also can produce electromagnetic interference (EMI) fast, be commonly called " noise " and exist to conduct with the form of radiated interference.
The application program of some voltage-releasing voltage stabilizers all needs that noise is low, efficiency is high, as data acquisition system and communication system.Although linear voltage regulator can meet the noise requirements of these application, but linear voltage regulator can not provide required efficiency.Traditional step-down switching regulator can meet the efficiency requirement of such application program, but can not meet low noise requirement.Therefore, need to provide step-down switching regulator circuit, high efficiency is provided, but limited voltage and current transfer ratio also has low noise applications.
Summary of the invention:
In sum, the object of the invention is: the voltage and current switching rate that provide high efficiency, can limit and the step-down switching regulator circuit of low noise applications.
Technical solution of the present invention:
In this invention and other objects of the present invention, step-down switching regulator circuit comprises the slew rate limit circuit of voltage conversioning rate limiting circuit and electric current.The slew rate limit circuit that can realize step-down switching regulator uses current programmed control or Duty ratio control.
Contrast patent documentation: CN2282698Y internal control type switch voltage stabilizer 96204039.8, CN201352323Y high-efficient synchronous rectification depressurization-type voltage stabilizer 200920130174.4
Brief description of the drawings:
Can more clearly understand above-mentioned object and feature of the present invention from being described in detail in drawing below, what identical reference number represented is identical structure:
Fig. 1 is a known step-down switching regulator schematic diagram;
Fig. 2 is that a known current programmed controlled hypotension switching regulator is realized schematic diagram;
Fig. 3 is that a known adjusting Duty ratio control step-down switching regulator is realized schematic diagram;
Fig. 4 is that another known current programmed controlled hypotension switching regulator is realized schematic diagram;
Fig. 5 is one and builds an illustrative low noise step-down switching regulator example with the principle of the invention;
Fig. 6 is an illustrative example of the circuit of Fig. 5;
Fig. 7 is another example of the circuit of Fig. 5;
Fig. 8 is another illustrative low noise step-down switching regulator example building with the principle of the invention;
Fig. 9 remains an illustrative low noise step-down switching regulator example building with the principle of the invention;
Figure 10 is the example of the circuit of key diagram 9.
Embodiment:
Background of the present invention is provided, describes known step-down switching regulator circuit below in detail.Then the low noise pressurizer of revising on these known voltage stabilizing circuits being disclosed has been described.
A, existing step-down switching regulator
Fig. 2 has shown the step-down switching regulator 70 of an existing current programmed control.Pressurizer 70 is similar to the pressurizer 10 of Fig. 1, has control circuit 24, by resistance 26, and current sense resistor 28, comparator 30, oscillator 32, SR latch 34, divider resistance 36 and 38, controlled current source 40, error amplifier 42, with reference voltage V
rEFC.
The operation of pressurizer 70 is as follows: in the beginning of one-period, and 32 oscillator clockings, set latch 34, makes controlled current source 12 generation current I
1thereby, open 14 and 16 transistors.Conversely, approximately voltage V
l(V
iN-V
oUTappear on inductance 20 to increase by the electric current I of inductance
l.Diode 18 is closed, and inductive reactance 28 conducts transistor 16 collector currents, approximates inductive current I
l.
Approximate (V
iN-I
l* R
1) V of voltage
ibe coupled to the anti-phase input of comparator 30.Error amplifier 42 amplifies reference voltage V
rEFCand feedback voltage V
fBCdifference produce error voltage vector.Error amplifier 42 provides very high gain (being generally 40-60 decibel).Divider resistance 36 and 38 is according to the output voltage V regulating
oUTratio setting V
fBC.Error voltage V
eCvecter cotpling is to controlling current source 40, by V
eCgeneration current I in proportion
2.Resistance 26 conduction current I
2.Voltage V
c, equal (V
iN-I
l* R
2), the noninverting input 30 of being coupled to comparator.
Comparator 30 produces the difference mark (I of output response
l* R
1-I
2* R
2).
When
time, comparator 16 is output as low level; When
time, the output of comparator 30 is high level; As inductive current I
lexceed ((R
2/ R
1) * I
2), comparator 30 is exported high level and reset latch 34, and controlled current source 12 is closed, thereby closes transistor 14 and 16.This variation V
lapproximately-V
oUT, forward bias diode 18, and make inductive current I
ldecline, until next clock pulse oscillator 32, set latch 34.
Therefore, in course of normal operation, when transistor is closed, inductance 16 electric current I
lexceed electric current I
2and resistance R
1and R
2the predeterminated level ((R arranging
2/ R
1) * I
2).If regulation output voltage V
outincrease exceed by divider resistance 36 and 38, reference voltage V
rEFC, error voltage V
eCand electric current I
2reduce the predetermined steady-state value that arranges, result is exactly, I
lbefore switch periods, exceed ((R
2/ R
1) * I
2) instead of in the time of steady operation.Shorten switching time and cause adjustment output voltage V
oUTreduce, until reach the steady-state value before it.
But, if the output voltage V regulating
oUTdrop to lower than predetermined steady-state value error voltage V
eCincrease electric current I
2increase.As a result, the duration that transistor 16 is opened lengthens, because I
lexceed ((R
2/ R
1) * I
2), more late in the steady operation time than it in switch periods.The duration that extends switch opens, cause regulation output voltage V
oUTincrease until reach former steady-state value.
In addition, existing switching regulator can be realized by Duty ratio control, and wherein pressurizer monitors output voltage, directly sets duty ratio.Fig. 3 has shown so existing Duty ratio control step-down switching regulator 80, operates as follows: the reference voltage V that error amplifier 142 amplifies
rEFVand feedback voltage V
fBVbetween difference to produce error voltage fixed.Error amplifier 142 provides very high gain (being generally 40-60 decibel).Divider resistance 136 and 138 in proportion with regulate output voltage V
oUTv is set
fBV.Comparator 130 has a noninverting input coupling error voltage V
eV, and anti-phase input is coupled to the output voltage V of saw-toothed wave generator 132
s.
At the beginning of each clock cycle, V
slower than V
eV, the output of comparator 130 is high level, controlled current source 12 derived current I
1, transistor 14 and diode 16 conductings, diode 18 ends.Approximately V
l(V
iN-V
oUT) voltage appear on inductance 20, make the electric current I by inductance
lincrease.Work as V
shigher than V
eVcomparator 130 is closed controlled current source 12, transistor 14 and 16(diode 18 and is opened).In the current-mode pressurizer 70 of Fig. 2, in output voltage V
oUTplace, inductance 20 and electric capacity 22 form a low pass filter eliminates switching frequency and the harmonic wave thereof of element.
In course of normal operation, if regulation output voltage V
oUTdrop to lower than by divider resistance 136 and 138, reference voltage V
rEFCthe predetermined steady-state value arranging, V
eCincrease, therefore at the later stage of clock cycle V
sexceed V
eV, cause and cause comparator 130 to extend the time of transistor 16 conductings.Therefore, flow through the electric current I of inductance 20
lincrease V
oUTincrease until reach former steady-state value.If but V
oUTincrease higher than expect steady-state value, V
eVreduce, therefore early stage in the clock cycle, V
sjust exceed V
eV, make comparator 130 shorten the time to transistor 16 conductings.As a result, flow through the electric current I of inductance 20
land V
oUTdecline, until it arrives its steady-state value in the past.
The voltage conversioning rate of the existing voltage-releasing voltage stabilizer of Fig. 2 and Fig. 3 is mainly that the characterisitic function of transistor 14 and 16 embodies.Before conducting, the base voltage of transistor 14 is about V
in, its collector voltage closely.After conducting, the base voltage of transistor 14 is about (V
iN(V
bE) transistorized V
bEthe about 0.7V of conducting voltage), its collector voltage is about V
iN.In the time of switch opens, electric current I
1a big chunk electric charge be full of the relatively large base stage-collector capacitance of transistor 14.This often limit transistor 14 in the switching rate of collector electrode, therefore limited the positive voltage switching rate of transistor 16 and inductance input node V
sW.
For closing function, current source 12 is closed, and removes the base current of transistor 14, closes the base current of transistor 14 and cut-out transistor 16.In the time of transistor 14 not conducting, the collector capacitance of transistor 16 is unique drive currents of transistor 16, and is the unique natural limit of negative voltage transition speed.Negative voltage transition speed depends on the current gain (β) of the level of output loading and the transistor of active area 16, conventionally faster than positive voltage switching rate.
Forward current transfer ratio is limited to PNP transistor 14 unit gain frequency (f
t) and the β value of transistor 16.In the circuit of Fig. 2 and Fig. 3, negative current transfer ratio is conventionally faster than the switching rate of forward current.In the time that current source 12 and transistor 14 are closed, the product of the collector capacitance of transistor 16 and negative voltage transition speed equals electric current, and it provides the base drive of transistor 16, until node V
sWa little less than earth potential and diode 18 conductings.When diode 18 is opened, the base stage of transistor 16 and emitter stop voltage revolution.Therefore, the base stage of driving transistors 16 is approximately zero, and the emitter current of transistor 16 is closed rapidly.This negative current conversion be promptly, uncontrolled.
Fig. 4 has shown the schematic diagram of the step-down switching regulator 90 of the current programmed control of employing of another previously known.Pressurizer 90 is devices 70 of similar Fig. 2, also comprises capacitor 74, diode 76 and 78, and resistor 82 and 84 also has circuit 86.In addition in Fig. 2, control current source 112 and NPN transistor 114 and replace respectively controlled current source 12 and PNP transistor 14.
The class of operation of pressurizer 90 is similar to pressurizer 70, and in order to raise the efficiency, it also has other circuit.Especially, the collector electrode of triode 114 is connected to a mark terminal " BOOST ", and this is to be connected to V
oUTelectric capacity 74, diode 76.In course of normal operation, after transistor 16 is closed, V
sWlower than earth potential, diode 76 conductings, capacitor 74 is full of, the about V of voltage
oUT.In next switch periods, when transistor 16 is opened switch, V
sWbecome about V
iN, diode 76 conductings, and " BOOST " node is increased to approximately (V
iN+ V
oUT).Like this, open when transistor 114, its emitter voltage exceedes input voltage.This allows transistor 114 driving transistorss 16 saturated to approaching, thereby reduces to greatest extent the voltage drop of transistor 16 and raise the efficiency.
Driving transistors 16 supersaturation are very inconvenient, because can cause turn-off delay very long.In order to prevent that transistor 16 is too saturated, several known in the industry technology of circuit 86 use itself are just starting to eliminate in saturated the driving of transistor 114 base stages.
Resistance 82 and 84 is coupled to respectively the base-emitter knot of transistor 114 and transistor 16.These resistance contribute to reduce the turn-off time of transistor 114 and 16, and the path of some leakage currents is provided.
B, low noise voltage-releasing voltage stabilizer
Fig. 5 has shown the schematic diagram of the example of a low noise step-down switching regulator of the present invention, in the contactor pressurizer 70 that is similar to Fig. 2, realizes.As mentioned above, transistor 14 and 16 provides the positive voltage slew rate limit characteristic of the step-down switching regulator in Fig. 2 and 3 in essence.Therefore, the example of low noise step-down switching regulator of the present invention comprises the limited characteristic of adjunct circuit negative voltage transition speed and positive and negative current conversion rate.
Particularly, pressurizer 170 comprises negative voltage transition rate limiter circuitry 44, and it is coupling in the V of transistor 16
iNand between base, the slew rate limiter circuit 46 of positive and negative electric current, is coupled to V
inwith node V
swwith V
delectric current inductive sensor 48.Have below more detailed description, in the time that switch disconnects, circuit 44 provides the base drive of transistor 16 to limit negative voltage transition speed.In addition, in switch opens with after closing, circuit 46 is eliminated and is driven, or driving is provided, and transistor 16 is Limited Current positive/negative-pressure switching rate respectively.
Fig. 6 has shown the example of low noise step-down switching regulator in Fig. 5.Negative voltage transition rate limiter circuitry 44 comprises capacitor 50, transistor 52 and 54, resistance 56 and 58.The capacitor 50 of the input of transistor 52 and 54 and a Darlington configuration is coupled, and is then connected to V
iN.The slew rate limiter circuit 46 of electric current comprises transistor 60 and 62, current source 64, diode 66.
When transistor 14,16 is connected, at the base voltage of transistor 16 greatly about input voltage, by the electric current I of capacitor 50
c50negligible, resistance 56 and 58, transistor 52 and 54 is closed.Current source 64 conduction current I
3, flow through diode 66.In the base stage of transistor 60 and the voltage approximately equal of emitter, therefore transistor 60 is closed.As described below, the voltage difference V of inductive sensor 48
s1be approximately zero, transistor 62 is closed.
In the time that switch cuts out, transistor 14 is closed, and when the base voltage of transistor 16 starts to decline, capacitor 50 and resistance 56 and 58 start generation current I
c50.When resistance 56 voltage drops are greater than V
bE, transistor 52 and 54 is opened, and the base drive of supply transistor 16, limits negative voltage transition speed.Because compared transistor 54,52, transistor needs the drive current of hundreds of microampere base stage, and transistor 52 can minimum (1 ×) transistor.On the contrary, due to transistor 54 must supply transistor 16 base stage the drive current of tens milliamperes, transistor 54 must be greater than minimum dimension (for example 10 ×).
Negative voltage transition rate limit is:
V
bEtransistorized conducting voltage, C
50capacitor 50, R
56the resistance value of resistance 56.Therefore, to C in circuit
50, R
56assignment, can limit required negative voltage transition speed.
Once at node voltage V
sWa value that is stabilized to near-earth electromotive force, the electric current that capacitor 50 produces can be ignored, and therefore transistor 52,54 closes.In the time of the drive current not having deliberately, resistance 58 turn-offs transistor 54, also can prevent that transistor 54 from puncturing.
Induced electricity sensor 48 has a value L
1, in order to induced current rate of change.In the time that electric current turns round, the voltage V of induced electricity sensor
s1=(V
sN-V
d) equal:
(dI/dt) be by the current changing rate of inductance 48.
Before closing, transistor 60 base stages and emitter voltage approximately equal, transistor 60 is closed.(dI/dt) by inductance 48 is approximately zero, therefore V
s1be approximately zero, transistor 62 is closed.In the time that switch cuts out, the emitter current of transistor 16 starts to reduce.V
s1be directly proportional to the negative current rate of change in transistor 16.Work as V
s1than less-V
bEthe base-emitter voltage of transistor 60 exceedes transistorized conducting voltage, opens the base drive of transistor 60 supply transistors 16, and the switching rate of restriction negative current exists:
in the time that switch cuts out, transistor 62 still keeps closing.Because with respect to transistor 16, transistor 60 must supply base stage the drive current of tens milliamperes, for example, so transistor 60 must be greater than minimum dimension (, 10 ×).
Before switch opens, the base stage of transistor 60 and 62 and emitter voltage are about earth potential, and therefore transistor 60,62 is closed.In the time of switch opens, transistor 16 emitter currents increase.V
s1be directly proportional to the positive current rate of change of transistor 16.Work as V
s1be greater than approximately+V
bEtime, transistor 62 is opened, and makes the base current skew of transistor 16, has therefore limited the forward current transfer ratio of pressurizer 270:
in the time of switch opens, transistor 60 is still closed.Because transistor 62 must supply transistor 16 base stage the drive current of tens milliamperes, transistor 62 must be greater than minimum dimension (for example, 10 ×).
The slew rate limit of positive and negative electric current is at about identical size (V
bE/ L
1).According to this point, inductance L
1value can be selected.
Fig. 7 has shown another example of the step-down switching regulator of Fig. 5.The slew rate limiter circuit 46 of electric current comprises transistor 60,62 and divider resistance 68 and 72.Divider resistance 68 and 72 has equal resistance.
The value of inductive sensor 148 is L
2, in order to induced current rate of change.Under electric current revolution, inductive sensor 148 voltage V
s2=(V
sW-V
d) equal:
(dI/dt) be by the current changing rate of inductance 148.
Before switch cuts out, approximate V at the base voltage of transistor 60
bE, lower than the emitter voltage of transistor 60, so transistor 60 is closed.(dI/dt) by inductance 148 is approximately zero, therefore V
s2also having the voltage on resistance 68 and 72 is almost zero, and therefore transistor 62 is closed.When switch cuts out, the emitter current of transistor 16 starts to reduce.V
s2be directly proportional to the negative current rate of change at transistor 16.Work as V
s2be less than (2*V
bE), transistorized base-emitter voltage exceedes the conducting voltage of transistor 60, and transistor 60 conductings are with supply transistor 16 base drive, thus the switching rate of restriction negative current:
under the state of closing at switch, transistor 62 still keeps closing.
Before opening, the base-emitter voltage of transistor 60 and 62 is approximately zero, and therefore transistor the 60, the 62nd, is closing.In the time of switch opens, transistor 16 emitter currents increase.V
s2be directly proportional to transistor 16 positive current rates of change.Work as V
s2be greater than (+2*V
bE), due to the effect of voltage divider resistance 68 and 72, the base voltage of transistor 62 is about V
bE.Transistor 62 is opened, and makes the base current skew of transistor 16, and the positive current rate of change that therefore limits pressurizer 310 exists:
in the time of switch opens, transistor 60 still keeps closing.
The slew rate limit of positive and negative electric current is about identical size (2*V
bE/ L
2).According to this one-level, inductance L
2value can select.
As shown in Figure 8, the identical negative voltage transition speed and one of description above extremely just, the limiting circuit of a utmost point negative current switching rate, also can in step-down switching regulator 380, realize, comprise Duty ratio control.
Fig. 9 has shown another low noise step-down switching regulator in an example of the present invention, realizes the contactor pressurizer 90 that is similar to Fig. 4.Low noise step-down switching regulator comprises the circuit of the switching rate of the positive and negative voltage conversioning rate of restriction and positive and negative electric current.
Particularly pressurizer 190 comprises the positive and negative voltage conversioning rate limiter circuitry 92 being coupling between transistor 114 base stages and earth potential, is coupled to V
iNpositive and negative voltage conversioning rate limiter circuitry 94, the base stage of transistor 114, node V
sWwith the V on inductive sensor 248
d.Have more detailed description below, in switch opens with while closing, circuit 92 removes driving from transistor 114 base stages, or the base drive of transistor 114 is provided, and limits respectively positive and negative voltage conversioning rate.In addition,, in switch opens with while closing, circuit 94 removes driving from transistor 114 base stages, or the base drive of transistor 16 is provided, and limits respectively positive and negative voltage conversioning rate.
Figure 10 has shown an illustrative example of the step-down switching regulator of Fig. 9.Voltage conversioning rate limiter circuitry 92 comprises capacitor 88 and resistance 182.The slew rate limiter circuit 94 of electric current comprises transistor 60,62, resistance 68 and 72.Anti saturation circuit 86 comprises resistance 96, NPN transistor 98, PNP transistor 100.
When current source is opened, controlled current source 212 generation current I
5.Electric current I
5to select like this: the base stage of the current supply transistor 114 of nearly half, electric current conduction flow is crossed resistance 182.Electric current I
5second half can give electric capacity 88 charge.Resistance 182 flows through maximum current and approximates (V
bE/ R
182), R
182it is the resistance of resistance.Select like this R
182so, (V
bE/ R
182) be several times of driving transistors 114 base currents, so (I
5/ 2) be approximately (V
bE/ R
182) (for example, several milliamperes).
In the time that transistor 114 and 16 is opened, the base voltage of transistor 114 (with the voltage of capacitor 88) is approximately V
iN, by the electric current I of capacitor 88
c88negligible.The base-emitter voltage of transistor 60 is for negative, and therefore transistor 60 is closed.As described below, by inductive sensor L
3voltage V
s3be approximately zero, transistor 62 is closed.
In the time that switch disconnects, current source 212 is closed, when the base voltage of transistor 114 starts to be transformed into negative.The electric current I of capacitor 88
c88equal:
C
eXTbeing electric capacity 88 electric capacity, is (dV/dt) the negative voltage transition speed in transistor 114 base stages.In closing, provide maximum current to be about (I by capacitor 88
5/ 2), therefore, negative voltage transition rate limit is:
Before switch opens, node V
sWdefinite value is near earth potential, and the voltage of capacitor 88 is approximately zero, I
c88inappreciable.At switch connection, current source 212 charges to capacitor 88, and the electric current that departs from of transistor 116 base stages passes through resistance 182, carrys out Limited Current positive voltage switching rate.Positive voltage slew rate limit is:
Positive and negative voltage slew rate limit is in roughly equal size.Based on this one-level, the value C of circuit
eXTcan be set up.
The value of inductive sensor 248 is L
3, in order to induced current rate of change.In the revolution of electric current, flow through the voltage (V of inductive sensor
s3=(V
sW-V
d)) equal:
(dI/dt) be by the current changing rate of inductance 248.
Before closing, the base-emitter voltage of transistor 60 is for negative, and therefore transistor 60 is closed.(dI/dt) by inductance 248 is approximately zero, therefore V
s3be approximately zero, therefore transistor 62 is also closed.In the time that switch cuts out, the emitter current of transistor 16 starts to reduce.V
s3be directly proportional to the negative current rate of change of transistor 16.Work as V
s3be less than (2*V
bE), the base-emitter voltage of transistor 60 exceedes transistorized conducting voltage, and transistor 60 is opened, and the base drive of supply transistor 16 limits the switching rate of negative current:
In the time that switch cuts out, transistor 62 keeps closing.
Before opening, transistorized 60 and 62 base-emitter voltages are approximately zero, and therefore transistor the 60, the 62nd, closes.After switch opens, the emitter current of transistor 16 starts to increase.V
s3be directly proportional to the negative current rate of change of transistor 16.Work as V
s3be greater than (+2*V
bE), transistor 62 conductings, transistor 114 base currents depart from, and have therefore limited the positive current rate of change of pressurizer 290:
In the time of switch opens, transistor 60 still keeps closing.
The size of positive and negative current changing rate restriction is roughly equal.Based on this point, the value of inductive sensor L3 is to select.
The circuit of deboost switching rate as shown in figure 10 and the switching rate of electric current also can be realized in the step-down switching regulator that comprises Duty ratio control.
The operation of anti saturation circuit 86 is as follows.Before opening, transistor the 98, the 100th, closes.When transistor 114 is opened, its emitter voltage is increased to and exceedes input voltage, and transistor 114 starts driving transistors 16 and approaches saturated.Be greater than the approximately (2*V of collector voltage of transistor 16 at the base voltage of transistor 98
bE) time, transistor 98 and 100 is just opened, and the ideal base drive current of transistor 114 is transferred to earth potential.Resistance 96 arranges the collector emitter voltage V of transistor 16
cE16value is: V
cE16≈ V
r3
V
r3it is the voltage drop of resistance 96.V
r3approximate (I
5* R
3), wherein I
5the electric current that controlled current source 212 provides, R
3the resistance of resistor 96.
The principle according to the present invention, people can find, and it can also be applied to other circuit, and for purposes of illustration, the present invention is unrestricted, limited by claim of the present invention.
Claims (9)
1. a low noise step-down switching regulator for programmable voltage slew rate limiter, is characterized in that: have the first end switching transistor that is coupled to input node, the second terminal, and the 3rd terminal; Have an inductor, its first terminal is coupled to the 3rd end of switching transistor, and the second end is coupled to output node; Have the first circuit, its first terminal is coupled to the second end of switching transistor, and the second end is connected to input node, in the 3rd end deboost switching rate of switching transistor to the first predetermined value; There is second circuit, the first terminal of the first terminal coupling inductance, the second end of the second terminal coupling inductor, the 3rd end is coupled to the second end of switching transistor, second circuit in the 3rd terminal Limited Current switching rate of this switching transistor in the second predetermined value.
2. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, is characterized in that: wherein the first circuit limits negative voltage transition speed to the first predetermined value at the 3rd end of switching transistor; Wherein the first circuit limits positive voltage switching rate to the first predetermined value at the 3rd end of switching transistor; Wherein the first circuit the 3rd end restriction one of switching transistor extremely just, a utmost point negative voltage transition speed is to the first predetermined value; Wherein second circuit limits negative current switching rate to the second predetermined value at the 3rd end of switching transistor; Wherein second circuit limits positive current switching rate to the second predetermined value at the 3rd end of switching transistor; Wherein second circuit the 3rd end restriction one of switching transistor extremely just, a utmost point negative voltage transition speed is to the second predetermined value; Wherein the first circuit limits positive voltage switching rate to the first predetermined value at the 3rd end of switching transistor; Wherein the first circuit limits the positive one-level negative voltage transition of one-level speed to the first predetermined value at the 3rd end of switching transistor; Wherein second circuit limits negative current switching rate to the second predetermined value at the 3rd end of switching transistor; Wherein second circuit limits positive current switching rate to the second predetermined value at the 3rd end of switching transistor; Wherein second circuit limits the positive one-level negative voltage transition of one-level speed to the second predetermined value at the 3rd end of switching transistor; Wherein switching transistor is made up of bipolar transistor, and wherein bipolar transistor comprises the base stage that is coupled to the collector electrode of input terminal and is coupled to the first terminal and second circuit the 3rd end of the first circuit, and the emitter of the first terminal of a coupling inductance.
3. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, is characterized in that: it is made up of the second end current-mode control circuit that is coupled to switching transistor; It is by forming with the control circuit of duty ratio of the second end coupling of switching transistor; Wherein the first circuit comprises: an electric capacity, and electric capacity the first terminal is connected to the second end of switching transistor, and electric capacity the second end is connected to input node, and wherein the electric capacity of the first predetermined value and capacitor is inversely proportional to.Wherein the first circuit also comprises: a resistance, and the first end of its one end coupling capacitance, the second end is connected to the second end of switching transistor, and wherein the resistance of the resistor of the first predetermined value and electric capacity are inversely proportional to; One is connected to input node by first end coupling, and the second terminal is coupled to the first end of resistance, the transistor of the second end of the 3rd end coupling resistance, and wherein the first predetermined value is and transistorized voltage, is directly proportional divided by the value after resistance and electric capacity; Wherein this second circuit comprises: the first transistor comprises that first end coupling is connected to input node, the second end of the second end coupling inductor, and the 3rd end is connected to the second end of switching transistor; Transistor seconds comprises the second end of the switching transistor that the first terminal is coupled to, the first terminal of the second end coupling inductance, and the second end of the 3rd end coupling inductor, wherein the second predetermined value is directly proportional divided by the value of the inductance of inductor to transistor seconds voltage; Described the second predetermined level equals the voltage of transistor seconds divided by the inductance of inductor; Described the second predetermined level equals the voltage of twice transistor seconds divided by the inductance of inductor.
4. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, it is characterized in that: a kind of method of current changing rate of step-down switching regulator of deboost, the method comprises: provide input at input node; The first end that having coupling and be connected to input node switching transistor is provided, and second end, and the 3rd end; The inductance that has first end coupling and be connected to this switching transistor the 3rd end is provided, and second end that is coupled to output node; The first terminal with the second end that is coupled to switching transistor is provided; The first circuit, by second terminal and the coupling of input node, deboost switching rate is the first predetermined value at the 3rd end of switching transistor; Second circuit provides the first end with the first terminal coupling inductor, the second end of the second end coupling inductor, and be connected to the 3rd end of the second end of switching transistor, and it is the second predetermined value that the 3rd end of this switching transistor is used for Limited Current transfer ratio.
5. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, is characterized in that: a kind of in the first node deboost switching rate of a step-down switching regulator, at the Section Point Limited Current transfer ratio of step-down switching regulator, control the Voltagre regulator at first node place at the 3rd node of adjusting and voltage-reduction switch, the 4th node is used for controlling electric current and comprises in the method for Section Point: at the 3rd node induced voltage rate of change; Provide the first electric current of the 3rd node voltage rate of change in proportion at the 3rd node, this first current limit voltage conversioning rate is in the first predetermined value of first node; The speed changing at second node induced current, provides the rate of change of the second electric current of the 4th node and the electric current of Section Point proportional at second node, the second current limit in the switching rate of the electric current of Section Point in the second predetermined value; The first Section Point is identical node, and the three or four node is identical node.
6. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, it is characterized in that: when input node produces input, output node produces output, it comprises: have the switching transistor of first end, the second end and the 3rd end, its first end is coupled to input node; First end is coupled to the 3rd end of switching transistor, and the second end is coupled to the inductor of output node; There is the first circuit of resistor, capacitor and the first transistor, there is the resistor of the first and second terminals, there is the capacitor of the first and second terminals, have the first, the second and the first transistor of the 3rd terminal; This capacitor-coupled, to the first end of the first transistor, is inputted the first end of node, the first end of this capacitive coupling resistance, the first end of the second end coupling resistance of electric capacity and the second end of the first transistor; The first transistor is the bipolar transistor with base stage and emitter and collector; The first end of electric capacity is coupled in collector electrode and the input node of the first transistor, the second terminal of capacitor is coupled in the base stage of resistance the first terminal and the first transistor, and the second terminal of resistor is coupled in the emitter of the first transistor and the second end of switching transistor.
7. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, it is characterized in that: produce output when input node generation input at output node, this pressurizer comprises: have first end and be coupled to input node switching transistor, the second terminal and the 3rd terminal; Inductor has first end and is coupled to switching transistor the 3rd end, and the second terminal is coupled to output node; The first circuit has resistor, capacitor and the first transistor, resistor the first and second terminals, capacitor has the first and second terminals, and the first transistor has the first, the second and the 3rd terminal, this the first transistor is connected to input node the first terminal, second first end of terminal coupling capacitance and the first terminal of resistance of this first transistor, this first transistor the 3rd terminal is coupled to the second terminal, the 3rd end and resistance second end of switching transistor, and the second end of capacitor is ground connection; The first transistor is the bipolar transistor with base stage and emitter and collector; The collector coupled of the first transistor is to input node, the first end of base stage coupling capacitance of this first transistor and the first terminal of resistance, and the second end of the emitter-coupled switching transistor of the first transistor and the second end of resistance.
8. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, it is characterized in that: when input node produces input, output node produces output, and this low noise step-down switching regulator comprises: have first end coupling and be connected to the switching transistor of inputting node, the second end and the 3rd end, have an inductor, inductor have be coupled to switching transistor the 3rd end the first terminal, be coupled to the second terminal of output node, have second and the 3rd transistorized second circuit, transistor seconds has first, second and the 3rd terminal, the 3rd transistor has first, second and the 3rd terminal, transistor seconds is coupled to the first terminal of input node, the second end of transistor seconds is coupled to the second end of inductor, the 3rd end of transistor seconds is coupled to the second end of switching transistor, the 3rd transistorized the first terminal is coupled to the second terminal of switching transistor, the first terminal of the 3rd transistor the second terminal coupling inductance, the second terminal of the 3rd transistor the 3rd terminal coupling inductance, transistor seconds has the bipolar transistor of collector electrode, base stage and emitter, the 3rd transistor has the bipolar transistor of collector electrode, base stage and emitter, the collector electrode of transistor seconds is connected to input node, the second end of the base stage coupling inductor of transistor seconds, and the emitter of transistor seconds is connected to the second end of switching transistor, the 3rd transistorized collector electrode is connected to the second end of switching transistor, the first terminal of the 3rd transistorized base stage coupling inductance, the second end of the 3rd transistorized emitter-coupled inductor.
9. the low noise step-down switching regulator of a kind of programmable voltage slew rate limiter according to claim 1, it is characterized in that: produce an output signal, when input node produces input, output node produces output, and this low noise step-down switching regulator comprises: a kind of device between switched input signal coupling input node and output node; Current conversion rate sensing device and switching device and output node coupling; The voltage conversioning rate of limit switch pressurizer is a kind of device of the first predetermined value, voltage limiting device and input node and switching device coupling; The current conversion rate of limit switch pressurizer is the device of the second predetermined value, current-limiting apparatus and current changing rate checkout gear and switching device coupling; The first predetermined value that wherein voltage conversioning rate restraint device restriction negative voltage transition speed is switching regulator; The first predetermined value that wherein voltage conversioning rate restraint device restriction positive voltage switching rate is switching regulator; The first predetermined value that wherein voltage conversioning rate restraint device restriction negative voltage transition speed and positive voltage switching rate are switching regulator; Wherein current conversion rate limitation devices, the second predetermined value that restriction negative current rate of change is switching regulator; Current conversion rate limitation devices wherein, the second predetermined value that to have limited positive current rate of change be switching regulator; Wherein current conversion rate limitation devices, the second predetermined value that restriction negative current transfer ratio and positive current rate of change are switching regulator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320761208.6U CN203813665U (en) | 2013-11-27 | 2013-11-27 | Low-noise step-down switching voltage regulator with programmable voltage conversion rate limiter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320761208.6U CN203813665U (en) | 2013-11-27 | 2013-11-27 | Low-noise step-down switching voltage regulator with programmable voltage conversion rate limiter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203813665U true CN203813665U (en) | 2014-09-03 |
Family
ID=51452364
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320761208.6U Expired - Lifetime CN203813665U (en) | 2013-11-27 | 2013-11-27 | Low-noise step-down switching voltage regulator with programmable voltage conversion rate limiter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203813665U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103647451A (en) * | 2013-11-27 | 2014-03-19 | 苏州贝克微电子有限公司 | Low-noise voltage step-down switching regulator with programmable voltage switching rate limiter |
| CN110557034A (en) * | 2019-10-08 | 2019-12-10 | 重庆凯米尔汽油机有限公司 | Pre-stage voltage stabilizing system of intermediate-frequency permanent magnet power generation welding machine |
-
2013
- 2013-11-27 CN CN201320761208.6U patent/CN203813665U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103647451A (en) * | 2013-11-27 | 2014-03-19 | 苏州贝克微电子有限公司 | Low-noise voltage step-down switching regulator with programmable voltage switching rate limiter |
| CN110557034A (en) * | 2019-10-08 | 2019-12-10 | 重庆凯米尔汽油机有限公司 | Pre-stage voltage stabilizing system of intermediate-frequency permanent magnet power generation welding machine |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9991794B2 (en) | Hybrid capacitive-inductive voltage converter | |
| Yousefzadeh et al. | A digitally controlled DC/DC converter for an RF power amplifier | |
| US9529373B2 (en) | Switching regulator and control circuit and control method therefor | |
| CN100511941C (en) | Control circuit and control method for DC-DC converter | |
| US9614437B2 (en) | Switching regulator and control circuit and control method therefor | |
| KR101045737B1 (en) | Constant on-time regulator with internal ripple generation and improved output voltage accuracy | |
| US8350541B2 (en) | Control circuit and method for a soft-start scheme of a switch mode power supply for a power amplifier | |
| US7274265B2 (en) | PWM controller with temperature regulation of switching frequency | |
| CN103269161B (en) | Constant-current output BUCK power circuit | |
| CN106788398A (en) | Clock division circuits, control circuit and power management integrated circuit | |
| CN100479310C (en) | Switching power supply apparatus | |
| EP3780369A1 (en) | A buck converter with a current-mode regulator | |
| CN103051220B (en) | Switching Power Supply and controller thereof | |
| CN106655769A (en) | Adaptive voltage regulator and voltage regulating method | |
| CN109391147A (en) | Step-down voltage converter | |
| CN104617771A (en) | Switching power converter system and control method thereof | |
| EP2028751B1 (en) | Low noise step-down switching regulator circuits with programmable slew rate limiter and method | |
| CN103618453A (en) | Switching regulator circuit | |
| CN114337267A (en) | Voltage control circuit and method based on COT (chip on Board) architecture and power supply equipment | |
| CN203562957U (en) | Switching voltage regulator circuit | |
| Villalva | Input-controlled buck converter for photovoltaic applications: modeling and design | |
| CN203813665U (en) | Low-noise step-down switching voltage regulator with programmable voltage conversion rate limiter | |
| CN107508466A (en) | Boost-voltage regulator with efficient soft starting circuit | |
| CN104485819B (en) | A kind of booster circuit | |
| CN103647451A (en) | Low-noise voltage step-down switching regulator with programmable voltage switching rate limiter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: 215000 Building 1, No. 150, Jici Road, science and Technology City, high tech Zone, Suzhou City, Jiangsu Province Patentee after: Suzhou Baker Microelectronics Co.,Ltd. Address before: Room 1404, building 3, No. 209, Zhuyuan Road, high tech Zone, Suzhou, Jiangsu 215011 Patentee before: SUZHOU BAKER MICROELECTRONICS Co.,Ltd. |
|
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term |
Granted publication date: 20140903 |