CN206332611U - The low-voltage starting circuit of step-up switching power supply - Google Patents
The low-voltage starting circuit of step-up switching power supply Download PDFInfo
- Publication number
- CN206332611U CN206332611U CN201621091217.9U CN201621091217U CN206332611U CN 206332611 U CN206332611 U CN 206332611U CN 201621091217 U CN201621091217 U CN 201621091217U CN 206332611 U CN206332611 U CN 206332611U
- Authority
- CN
- China
- Prior art keywords
- circuit
- oscillator
- voltage
- switch
- auxiliary
- 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 - Fee Related
Links
Landscapes
- Dc-Dc Converters (AREA)
Abstract
The utility model discloses a kind of low-voltage starting circuit of step-up switching power supply, including the voltage source being sequentially connected in series, power tube, inductance and current foldback circuit, and it is connected in parallel on the pierce circuit between voltage source and inductance, pierce circuit is divided into magnet oscillator circuit and auxiliary oscillator circuit two parts, magnet oscillator circuit includes master oscillator, comparator, band-gap reference circuit, PWM comparators and switch S1, master oscillator is powered by voltage source, worked after voltage source rises to 1.9V with a frequency relatively stablized, lifting simultaneously maintains output voltage, channel frequency stability is high, auxiliary oscillator circuit includes auxiliary oscillator, input voltage and switch S2, auxiliary oscillator is powered by input voltage, 0.8V can starting of oscillation, the conducting and shut-off of power tube were controlled before 1.9V is risen to, make voltage source progressively lifting, operating voltage is reduced to greatest extent, extend the service life of battery.The utility model is beneficial to business development.
Description
Technical field
The utility model is related to IC design field, and in particular to a kind of low voltage starting electricity of step-up switching power supply
Road.
Background technology
Various portable type electronic products, such as camera, video camera, mobile phone, notebook computer, multimedia player are all needed
The power management chips such as DC-DC converter, this kind of portable set is wanted typically to be powered using battery, gross energy is limited, therefore, electricity
Source chip needs to reduce operating voltage to greatest extent, extends the service life of battery.Traditional DC-DC operating voltage is general
All in more than 1.0V.
DC-DC step-up switching power supplies are to work at a low input voltages, using controlling circuit turn-on and switch-off power
Pipe, when power tube is turned on, inductance storage energy；When power tube is turned off, inductance is released energy, and output capacitance is charged, defeated
Go out voltage rise.As input power as little as below 1.0V, if the driving voltage of DC-DC chips is derived from input power, chip
Portion's circuit cannot normal work, DC-DC just can not start；If the driving voltage of DC-DC chips is derived from output voltage,
Equally, chip can not start and carry out any boost action at all, and the excursion of input supply voltage is larger.
Utility model content
The purpose of this utility model is to overcome the deficiencies in the prior art there is provided a kind of low cost, channel frequency stability
It is high, it is adaptable to the low-voltage starting circuit of the larger step-up switching power supply of mains voltage variations.
The technical solution of the utility model is as follows：
A kind of low-voltage starting circuit of step-up switching power supply, including be sequentially connected in series voltage source, power tube, electricity
Sense and current foldback circuit, and the pierce circuit being connected in parallel between the voltage source and inductance, the pierce circuit
It is divided into magnet oscillator circuit and auxiliary oscillator circuit two parts, the magnet oscillator circuit includes master oscillator, comparator, band-gap reference
Circuit, PWM comparators and switch S1, the control end EN1 connections of the comparator and master oscillator, the PWM comparators and master
The control end EN2 connections of oscillator, the voltage source is connected to the negative pole of comparator, the positive pole of the comparator with it is described
PWM comparators are connected, and the band-gap reference circuit is used as the reference voltage source of the PWM comparators, one end of the switch S1
Be connected with master oscillator, the other end of the switch S1 is connected to the circuit of the power tube and inductance, thus with power tube and
Inductance formation is connected in parallel, and the conducting and disconnection of master oscillator are controlled by the switch S1, and the auxiliary oscillator circuit includes
Auxiliary oscillator, input voltage and switch S2, the auxiliary oscillator powered by input voltage, one end of the switch S2 and
Auxiliary oscillator is connected, the circuit of the other end of the switch S2 connection power tube and inductance, thus with power tube and electricity
Sense formation is connected in parallel, and the conducting and disconnection of power tube are controlled by the switch S2.
Further, in the above-mentioned technical solutions, the master oscillator employs ring oscillator structure, makes the main oscillations
Frequency of oscillation of the device in 1.9 ~ 8V supply voltage interval output 350kHz or so.
Further, in the above-mentioned technical solutions, overvoltage crowbar is provided with the master oscillator.
Further, in the above-mentioned technical solutions, the auxiliary oscillator also uses ring oscillator structure, makes this auxiliary
The starting of oscillation voltage of oscillator is helped to be down to 0.8V.
Compared with prior art, the beneficial effects of the utility model are：The utility model is directed to traditional input power electricity
Press excursion larger, in the case where considering commercial cost, devise 2 pierce circuits：Master oscillator and auxiliary oscillating
Device.Master oscillator is that voltage source is powered by output voltage, with a frequency relatively stablized after voltage source rises to 1.9V
Work, lifting simultaneously maintains output voltage, and channel frequency stability is high.Auxiliary oscillator is powered by input voltage, and 0.8V can rise
Shake, the conducting and shut-off of power tube were controlled before 1.9V is risen to, makes voltage source progressively lifting.Work is reduced to greatest extent
Make voltage, extend the service life of battery.
Brief description of the drawings
Fig. 1 is the circuit diagram of the low-voltage starting circuit of step-up switching power supply described in the utility model embodiment；
Fig. 2 is the internal circuit diagram of master oscillator described in the utility model；
Fig. 3 is the internal circuit diagram of auxiliary oscillator described in the utility model.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in detail.
As shown in figure 1, the utility model provides a kind of low-voltage starting circuit of step-up switching power supply, including it is sequentially connected in series
Voltage source 1, power tube 2, inductance 3 and the current foldback circuit 4 of connection, and be connected in parallel on the voltage source 1 and inductance 3 it
Between pierce circuit 5, the pierce circuit 5 is divided into magnet oscillator circuit and auxiliary oscillator circuit two parts by the present embodiment,
Wherein：
The magnet oscillator circuit includes master oscillator 61, comparator 62, band-gap reference circuit 63, PWM comparators 64 and opened
S1 is closed, the comparator 62 is connected with the control end EN1 of master oscillator 61, the control of the PWM comparators 64 and master oscillator 61
EN2 connections in end processed, the voltage source 1 is connected to the negative pole of comparator 62, and the positive pole of the comparator 62 is compared with the PWM
Device 64 is connected, the band-gap reference circuit 63 as the PWM comparators 64 reference voltage source, one end of the switch S1 with
Master oscillator 61 is connected, and the other end of the switch S1 is connected to the circuit of the power tube 2 and inductance 3, thus with power tube 2
It is connected in parallel with the formation of inductance 3, the conducting and disconnection of master oscillator 61 is controlled by the switch S1.The master oscillator 61 is leaned on
Output voltage is that voltage source 1 is powered, and is worked after voltage source 1 rises to 1.9V with a frequency relatively stablized, lifting is simultaneously
Maintain output voltage.
The auxiliary oscillator circuit includes auxiliary oscillator 71, input voltage 72 and switch S2, the auxiliary oscillator 71
Powered by input voltage 72, one end of the switch S2 is connected with auxiliary oscillator 71, the other end connection of the switch S2
The circuit of the power tube 2 and inductance 3, so as to be connected in parallel with power tube 2 and the formation of inductance 3, is controlled by the switch S2
The conducting and disconnection of power tube 2.Auxiliary oscillator 71 is powered by input voltage 72,0.8V can starting of oscillation, risen in voltage source 1
1.9V controlled the conducting and shut-off of power tube 2 in the past, made the progressively lifting of voltage source 1.
Ring oscillator is simple in construction because of its, it is easy to integrated, and is used for the design of many IC chips, but it vibrates
Frequency is influenceed larger by mains voltage variations, and the master oscillator 91 of the present embodiment employs ring oscillator as shown in Figure 2
Structure, VC1, VC2 are respectively overvoltage crowbar, and the output signal of PWM comparators, MP10 and MP11 carry for band-gap reference circuit
The image current of confession, the size of rational control image current and electric capacity C1, C2, i.e., can make master oscillator 1.9 ~ 8V's
Supply voltage interval output 350kHz or so frequency of oscillation.
The auxiliary oscillator 71 also uses ring oscillator structure, and it utilizes the principle of subthreshold conduction so that
Starting of oscillation voltage is down to 0.8V, but this auxiliary oscillator 71 frequency in 0.8V ~ 1.9V supply voltage is interval changes very greatly,
Very big surge current can be caused in the circuit start stage, cause the unstable of system.As shown in figure 3, M1 ~ M13 is low input
Voltage bias current circuit, this circuit major function is the biased electrical for producing a constant na level at a low input voltages
Stream.M8 ~ M13 is start-up circuit, and M3, M4 are operated in sub-threshold region；Constant-current source I1 and I4 is to electric capacity C1 discharge and recharges, the vibration
The nucleus module of device is two comparators, and M21, M22 composition COMP1, comparator threshold is higher, is the conduction threshold of M22 pipes；
M22, M23, M24, M25, M26, R2 constitute COMP2, and the comparator threshold is relatively low；SE is the switching signal of auxiliary oscillator 71,
SEB is SE inverted signal.When voltage source is less than 1.9V, SE is high level, and M17, M18 end, and does not influence R, S triggerings
The upset of device, auxiliary oscillator 71 works, and switch S1 disconnects, S2 closures；When voltage source is higher than 1.9V, SE is low electricity
Flat, auxiliary oscillator 71 is turned off, and switch S1 closures, S2 is disconnected, and M17, M18 are turned on, R=1, S=0, and AUXCLK is locked
For high level, power consumption is both reduced, R after auxiliary oscillator 71 is turned off is it also avoid, nondeterministic statement occur in S ends.
Its operation principle is：After circuit start, the starting of oscillation of auxiliary oscillator 71 first, voltage source 1 gradually rises, rise
During to 1.4V, the starting of oscillation of master oscillator 61, but now only auxiliary oscillating signal passes to the grid of power tube 2 by switching S2, when
When voltage source 1 is increased to 1.9V, auxiliary oscillator 71 is turned off, and the signal of master oscillator 61 passes to power tube 2 by switching S1
Grid, voltage source 1 continues to be increased to after the output voltage 3.3V of setting, and the unlatching of master oscillator 61 is controlled by feedback circuit
With shut-off, to maintain this output voltage.
Preferred embodiment of the present utility model is these are only, the utility model is not limited to, it is all in this practicality
Any modification, equivalent and improvement made within new spirit and principle etc., should be included in guarantor of the present utility model
Within the scope of shield.
Claims (4)
1. a kind of low-voltage starting circuit of step-up switching power supply, including be sequentially connected in series voltage source, power tube, inductance
And current foldback circuit, and the pierce circuit being connected in parallel between the voltage source and inductance, it is characterised in that：It is described to shake
Swing device circuit and be divided into magnet oscillator circuit and auxiliary oscillator circuit two parts, the magnet oscillator circuit include master oscillator, comparator,
Band-gap reference circuit, PWM comparators and switch S1, the control end EN1 connections of the comparator and master oscillator, the PWM ratios
Compared with the control end EN2 connections of device and master oscillator, the voltage source is connected to the negative pole of comparator, the positive pole of the comparator
It is connected with the PWM comparators, the band-gap reference circuit is used as the reference voltage source of the PWM comparators, the switch S1
One end be connected with master oscillator, the other end of the switch S1 is connected to the circuit of the power tube and inductance, so that and work(
Rate pipe and inductance formation are connected in parallel, and the conducting and disconnection of master oscillator, the auxiliary oscillating electricity are controlled by the switch S1
Road includes auxiliary oscillator, input voltage and switch S2, and the auxiliary oscillator is powered by input voltage, the switch S2's
One end is connected with auxiliary oscillator, and the other end of the switch S2 connects the circuit of the power tube and inductance, so that and power
Pipe and inductance formation are connected in parallel, and the conducting and disconnection of power tube are controlled by the switch S2.
2. the low-voltage starting circuit of step-up switching power supply according to claim 1, it is characterised in that：The master oscillator
Ring oscillator structure is employed, makes the master oscillator in 1.9 ~ 8V supply voltage interval output 350kHz or so oscillation frequency
Rate.
3. the low-voltage starting circuit of step-up switching power supply according to claim 2, it is characterised in that：The master oscillator
It is interior to be provided with overvoltage crowbar.
4. the low-voltage starting circuit of step-up switching power supply according to claim 1, it is characterised in that：The auxiliary oscillating
Device also uses ring oscillator structure, the starting of oscillation voltage of the auxiliary oscillator is down to 0.8V.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621091217.9U CN206332611U (en) | 2016-09-29 | 2016-09-29 | The low-voltage starting circuit of step-up switching power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621091217.9U CN206332611U (en) | 2016-09-29 | 2016-09-29 | The low-voltage starting circuit of step-up switching power supply |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206332611U true CN206332611U (en) | 2017-07-14 |
Family
ID=59286857
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621091217.9U Expired - Fee Related CN206332611U (en) | 2016-09-29 | 2016-09-29 | The low-voltage starting circuit of step-up switching power supply |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN206332611U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107800310A (en) * | 2017-11-17 | 2018-03-13 | 上海新进半导体制造有限公司 | The power source supply method and control chip of control chip in inverse-excitation type switch power-supply |
| CN108400704A (en) * | 2018-05-09 | 2018-08-14 | 无锡鸿恩泰科技有限公司 | Step-up DC-DC ultralow pressure cold start-up circuits |
| WO2020150158A1 (en) * | 2019-01-14 | 2020-07-23 | Texas Instruments Incorporated | Methods and apparatus to start converters into a pre-biased voltage |
-
2016
- 2016-09-29 CN CN201621091217.9U patent/CN206332611U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107800310A (en) * | 2017-11-17 | 2018-03-13 | 上海新进半导体制造有限公司 | The power source supply method and control chip of control chip in inverse-excitation type switch power-supply |
| CN107800310B (en) * | 2017-11-17 | 2020-07-10 | 上海新进半导体制造有限公司 | Power supply method of control chip in flyback switching power supply and control chip |
| CN108400704A (en) * | 2018-05-09 | 2018-08-14 | 无锡鸿恩泰科技有限公司 | Step-up DC-DC ultralow pressure cold start-up circuits |
| WO2020150158A1 (en) * | 2019-01-14 | 2020-07-23 | Texas Instruments Incorporated | Methods and apparatus to start converters into a pre-biased voltage |
| US10917005B2 (en) | 2019-01-14 | 2021-02-09 | Texas Instruments Incorporated | Methods and apparatus to start converters into a pre-biased voltage |
| US11611274B2 (en) | 2019-01-14 | 2023-03-21 | Texas Instruments Incorporated | Methods and apparatus to start converters into a pre-biased voltage |
| US11770067B2 (en) | 2019-01-14 | 2023-09-26 | Texas Instruments Incorporated | Methods and apparatus to start converters into a pre-biased voltage |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN206336142U (en) | Battery management system | |
| CN206332611U (en) | The low-voltage starting circuit of step-up switching power supply | |
| CN110323736A (en) | Power supply switch circuit and electronic equipment | |
| CN103594288A (en) | Relay driving device and driving method thereof | |
| CN107508458B (en) | Starting circuit of PWM chip of ultra-wide voltage auxiliary power supply | |
| CN204482092U (en) | A kind of non-isolated voltage-dropping type LED drive circuit of intelligent synchronization rectification | |
| CN203206118U (en) | Efficient DC/DC boost converting circuit | |
| CN110829557A (en) | Isolated electrolytic capacitor-free constant-current charging circuit and switching method thereof | |
| CN203722473U (en) | Embedded single-switch Buck-Boost converter | |
| CN203261052U (en) | Charging circuit utilizing battery of turned-off laptop | |
| CN206117538U (en) | Switching power supply circuit device that convergence was inputed in zero standby | |
| CN202189964U (en) | Energy-saving socket circuit for computer started up remotely | |
| CN212992001U (en) | Light-operated boost circuit with turn-off function | |
| CN204271916U (en) | A kind of auxiliary power supply circuit of Switching Power Supply | |
| CN212752233U (en) | MOS tube driving circuit | |
| CN204013231U (en) | A kind of boosted switch power supply | |
| CN209072364U (en) | A kind of synchronous rectification control chip and circuit | |
| CN206506464U (en) | A kind of domestic refrigerator compressor variable frequency controller | |
| CN201821265U (en) | Non-polar isolation reverse converter | |
| CN203618180U (en) | LED driving apparatus | |
| CN201928187U (en) | High-voltage start switch circuit and switch power applying high-voltage start switch circuit | |
| CN105337480A (en) | Grid driving circuit with switching tubes connected in parallel | |
| CN201467324U (en) | Low power consumption CPU standby commutation circuit | |
| CN206442559U (en) | A kind of LED drive circuit | |
| CN104470105A (en) | Logic protection amplifying grid drive system based on bootstrap circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20170714 Termination date: 20190929 |