CN112564471A - Working sequence control circuit in two-stage conversion circuit and method thereof - Google Patents
Working sequence control circuit in two-stage conversion circuit and method thereof Download PDFInfo
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- CN112564471A CN112564471A CN202011364797.5A CN202011364797A CN112564471A CN 112564471 A CN112564471 A CN 112564471A CN 202011364797 A CN202011364797 A CN 202011364797A CN 112564471 A CN112564471 A CN 112564471A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/36—Means for starting or stopping converters
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
Abstract
The invention discloses a working time sequence control circuit in a two-stage conversion circuit and a method thereof, belonging to the technical field of power supply, comprising a power supply unit, a voltage detection unit, a time sequence control unit, a voltage return difference unit and a signal connection and soft start unit, solving the technical problem of determining whether a DC-DC circuit normally starts to work or not by collecting and comparing the bus voltage.
Description
Technical Field
The invention belongs to the technical field of power supplies, and relates to a working sequence control circuit in a two-stage conversion circuit and a method thereof.
Background
In the AC-DC two-stage conversion circuit, a PFC circuit, such as a non-isolated BOOST circuit, is adopted at the front stage to obtain bus voltage; the bus voltage connection post-stage DC-DC conversion circuit comprises a conventional flyback circuit output and an auxiliary power supply circuit for supplying power to a system. When the input voltage of the DC-DC circuit is too low, the starting capability of the DC-DC circuit is poor, the starting impact current is increased, the bus voltage is increased by too much and not enough, the stable operation cannot be realized, and the design optimization of the transformer is difficult. Therefore, the adoption of a DC-DC circuit working in a wide range is not beneficial to the improvement of the performance of the whole machine.
However, the conventional circuit has application defects and shortcomings, in order to improve the overall efficiency of the product, reduce the volume of the product and reduce the cost, the input voltage of the post-stage DC-DC circuit needs to be set to a certain working range, the size of the bus voltage determines whether the DC-DC circuit starts to work normally, and the defects caused by the wide voltage range work of the DC-DC circuit are overcome.
When a traditional AC-DC circuit is powered on during startup, the starting voltage of the rear-stage DC-DC circuit is often lower than the rectification peak voltage of the input lowest voltage, the starting power is high, the bus voltage has high over-voltage under-voltage oscillation and unstable working conditions, the performance of the transformer cannot reach the optimal working condition, and the performance of the product is reduced.
Disclosure of Invention
The invention aims to provide a working sequence control circuit in a two-stage conversion circuit and a method thereof, which solve the technical problem that whether a DC-DC circuit normally starts working or not by collecting and comparing the bus voltage.
In order to achieve the purpose, the invention adopts the following technical scheme:
a working sequence control circuit in a two-stage conversion circuit comprises a power supply unit, a voltage detection unit, a sequence control unit, a voltage return difference unit and a signal connection and soft start unit;
the time sequence control unit is respectively connected with the power supply unit, the voltage detection unit, the voltage return difference unit and the signal connection and soft start unit;
the voltage detection unit samples the voltage of the bus to be detected;
the time sequence control unit is used for generating a time sequence signal, and the signal connection and soft start unit outputs a control voltage Vout through the time sequence signal;
the voltage return difference unit is used for setting the working return difference voltage of the measured voltage.
Preferably, the timing control unit includes a zener diode ZD2 and a capacitor C2, the power supply unit includes a diode D1, a resistor R5 and a resistor R4, the anode of the diode D1 is connected to the external power source Vin, the cathode is connected to one end of a resistor R5, the other end of the resistor R5 is connected to the power source VCC, the cathode of the zener diode ZD2 is connected to the power source VCC, the anode is connected to the ground, and the capacitor C2 is connected in parallel with the zener diode ZD 2.
Preferably, the voltage detection unit comprises a controllable voltage regulator Q1, a capacitor C4, a capacitor C1, a resistor R2 and a resistor R1, and a reference electrode of the controllable voltage regulator Q1 is connected with the bus to be tested through a resistor R1 and used for acquiring a voltage Vbus on the bus to be tested;
the reference electrode of the controllable voltage-stabilizing source Q1 is also connected with the ground wire through a resistor R2, and a capacitor C1 is connected with the resistor R2 in parallel;
the anode of the controllable voltage-stabilizing source Q1 is connected with the ground wire, and the cathode is connected with the reference electrode of the controllable voltage-stabilizing source Q1 through a resistor C4;
the cathode of the controllable voltage-stabilizing source Q1 is also connected with the power supply VCC through the resistor R4.
Preferably, the signal connection and soft start unit comprises a triode Q2, a triode Q3, a zener diode ZD1 and a capacitor C3, wherein an emitter of the triode Q2 is connected with a ground wire, and a base of the triode Q2 is connected with an anode of the zener diode ZD 1;
an emitting electrode of the triode Q3 is connected with a ground wire, a collecting electrode is connected with the control voltage Vout, the capacitor C3 is connected between the emitting electrode and the collecting electrode of the triode Q3, a base electrode of the triode Q3 is connected with the anode of the voltage stabilizing diode ZD1, and the cathode of the voltage stabilizing diode ZD1 is connected with the cathode of the controllable voltage stabilizing source Q1.
Preferably, the voltage return difference unit includes a resistor R3, one end of the resistor R3 is connected to the reference electrode of the controllable voltage regulator Q1, and the other end is connected to the collector of the triode Q2.
A working sequence control method in a two-stage conversion circuit comprises the following steps:
step 1: establishing a working sequence control circuit in the two-stage conversion circuit, wherein a control voltage Vout is connected with a control circuit enabling pin of a rear-stage circuit, the input voltage of the control circuit enabling pin of the rear-stage circuit is started at a high level, and the low level is not started;
step 2: when the external power supply Vin is powered on, the external power supply Vin supplies power to a capacitor C2 of a power supply Vcc node through a diode D1 and a resistor R5, and the power supply VCC quickly rises to a power supply voltage;
and step 3: at this time, due to the starting delay of a preceding stage PFC circuit on the tested bus and the influence of the rising time of the voltage Vbus on the tested bus, the voltage Vbus is lower than the starting threshold voltage Vth _ on of the reference electrode of the controllable voltage-stabilizing source Q1 at the moment, namely, the input voltage of the reference electrode of the controllable voltage-stabilizing source Q1 is smaller than the internal reference voltage thereof, the controllable voltage-stabilizing source Q1 is cut off, and the output thereof is at a high level;
at this time, the zener diode ZD1, the triode Q2 and the triode Q3 are all in a conducting state, and the control voltage Vout connected to the collector of the triode Q3 is pulled low, so that the subsequent circuit cannot be started;
and 4, step 4: with the increase of time, after the voltage Vbus rises to be higher than the starting threshold voltage Vth _ on, the controllable voltage stabilizing source Q1 is conducted, the output of the controllable voltage stabilizing source Q1 is at a low level which is not enough to enable the voltage stabilizing diode ZD1 to work, and the voltage stabilizing diode ZD1, the triode Q2 and the triode Q3 are all in a cut-off state;
the control voltage Vout of the collector of the triode Q3 is released, the control voltage Vout is connected with the soft start capacitor C3, and the voltage on the soft start capacitor C3 is gradually increased, so that the later-stage circuit is subjected to soft start;
and 5: the resistor R3 is a positive feedback resistor, after the voltage on the tested bus exceeds the starting threshold voltage Vth _ on, because the triode Q2 is cut off, the resistor R3 is not connected with the resistor R2 in parallel, the proportion of the voltage value of the reference electrode input into the controllable voltage-stabilizing source Q1 is increased, the voltage of the tested bus drops to a certain voltage near the starting threshold voltage Vth _ on, the controllable voltage-stabilizing source Q1 is still not cut off again, the capacitor C4 slows down the change speed of the controllable voltage-stabilizing source Q1, and the external DC-DC circuit is ensured to meet the stability requirement after the starting of the starting threshold voltage Vth _ on;
when the bus voltage is reduced, the off-threshold voltage Vth _ off of the off-bus voltage value of the external DC-DC stop work is determined by the resistor R1 and the resistor R2, and the calculation expression of the off-threshold voltage Vth _ off is as follows:
Vth_off×R2/(R1+R2)＝2.5V；
due to the existence of R3, the bus voltage is turned on and off, and a return difference voltage delta Vbus exists, and the calculation expression is as follows:
ΔVbus＝Vth_on-Vth_off。
preferably, in step 4, as the voltage on the bus under test rises, the voltage Vbus reaches the turn-on threshold voltage Vth _ on, and the calculation expression is:
Vth_on×(R2×R3/(R2+R3))/(R1+R2×R3/(R2+R3))＝2.5V。
preferably, the resistor R2 is selected as an initial value, the resistances of the resistor R1 and the resistor R3 are calculated according to the requirements of Vth _ on and Vth _ off, and the resistor R1 is obtained by selecting four equivalent resistors to be connected in series equivalently.
The invention relates to a working sequence control circuit in a two-stage conversion circuit and a method thereof, which solve the technical problem that whether a DC-DC circuit normally starts to work or not by collecting and comparing the bus voltage.
Drawings
FIG. 1 is a schematic block diagram of the present invention;
FIG. 2 is a circuit diagram of embodiment 1;
fig. 3 is a circuit diagram of embodiment 3.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
the working sequence control circuit in the two-stage conversion circuit shown in fig. 1-2 comprises a power supply unit, a voltage detection unit, a sequence control unit, a voltage return difference unit and a signal connection and soft start unit;
the time sequence control unit is respectively connected with the power supply unit, the voltage detection unit, the voltage return difference unit and the signal connection and soft start unit;
the voltage detection unit samples the voltage of the bus to be detected;
the time sequence control unit is used for generating a time sequence signal, and the signal connection and soft start unit outputs a control voltage Vout through the time sequence signal;
the voltage return difference unit is used for setting the working return difference voltage of the measured voltage.
Preferably, the timing control unit includes a zener diode ZD2 and a capacitor C2, the power supply unit includes a diode D1, a resistor R5 and a resistor R4, the anode of the diode D1 is connected to the external power source Vin, the cathode is connected to one end of a resistor R5, the other end of the resistor R5 is connected to the power source VCC, the cathode of the zener diode ZD2 is connected to the power source VCC, the anode is connected to the ground, and the capacitor C2 is connected in parallel with the zener diode ZD 2.
Preferably, the voltage detection unit comprises a controllable voltage regulator Q1, a capacitor C4, a capacitor C1, a resistor R2 and a resistor R1, and a reference electrode of the controllable voltage regulator Q1 is connected with the bus to be tested through a resistor R1 and used for acquiring a voltage Vbus on the bus to be tested;
the reference electrode of the controllable voltage-stabilizing source Q1 is also connected with the ground wire through a resistor R2, and a capacitor C1 is connected with the resistor R2 in parallel;
the anode of the controllable voltage-stabilizing source Q1 is connected with the ground wire, and the cathode is connected with the reference electrode of the controllable voltage-stabilizing source Q1 through a resistor C4;
the cathode of the controllable voltage-stabilizing source Q1 is also connected with the power supply VCC through the resistor R4.
Preferably, the signal connection and soft start unit comprises a triode Q2, a triode Q3, a zener diode ZD1 and a capacitor C3, wherein an emitter of the triode Q2 is connected with a ground wire, and a base of the triode Q2 is connected with an anode of the zener diode ZD 1;
an emitting electrode of the triode Q3 is connected with a ground wire, a collecting electrode is connected with the control voltage Vout, the capacitor C3 is connected between the emitting electrode and the collecting electrode of the triode Q3, a base electrode of the triode Q3 is connected with the anode of the voltage stabilizing diode ZD1, and the cathode of the voltage stabilizing diode ZD1 is connected with the cathode of the controllable voltage stabilizing source Q1.
Preferably, the voltage return difference unit includes a resistor R3, one end of the resistor R3 is connected to the reference electrode of the controllable voltage regulator Q1, and the other end is connected to the collector of the triode Q2.
In this embodiment, the voltage Vbus, the external power Vin, and the power VCC are all provided by an external front-stage AC-DC circuit, and the control voltage Vout is used to control the rear-stage DC-DC circuit.
After the input is electrified, an auxiliary voltage VCC is provided, due to the initial electrification, the voltage of the bus voltage Vbus does not reach the starting set threshold voltage Vth _ on, and the output end of the Q1 is at a high level. At this time, the zener diode ZD1, the transistor Q2 and the transistor Q3 are all in a conducting state, the control voltage Vout output by the transistor Q3 is pulled low, the control circuit enable pin of the control voltage Vout, which is connected with the rear-stage DC-DC circuit, is also pulled low, and at this time, the rear-stage DC-DC circuit is set to be not started.
When the voltage Vbus reaches the turn-on threshold voltage Vth _ on, the control voltage Vout is released, and the subsequent-stage DC-DC circuit is set to be turned on with the charging of the soft-start capacitor C3, so that the setting of the operating lowest voltage range of the second-stage circuit can be realized.
Example 2:
the method for controlling the operation timing in the two-stage conversion circuit according to embodiment 2 is implemented on the basis of the operation timing control circuit in the two-stage conversion circuit according to embodiment 1, and specifically includes the following steps:
step 1: establishing a working sequence control circuit in the two-stage conversion circuit, wherein a control voltage Vout is connected with a control circuit enabling pin of a rear-stage circuit, the input voltage of the control circuit enabling pin of the rear-stage circuit is started at a high level, and the low level is not started;
step 2: when the external power supply Vin is powered on, the external power supply Vin supplies power to a capacitor C2 of a power supply Vcc node through a diode D1 and a resistor R5, and the power supply VCC quickly rises to a power supply voltage;
and step 3: at this time, due to the starting delay of a preceding stage PFC circuit on the tested bus and the influence of the rising time of the voltage Vbus on the tested bus, the voltage Vbus is lower than the starting threshold voltage Vth _ on of the reference electrode of the controllable voltage-stabilizing source Q1 at the moment, namely, the input voltage of the reference electrode of the controllable voltage-stabilizing source Q1 is smaller than the internal reference voltage thereof, the controllable voltage-stabilizing source Q1 is cut off, and the output thereof is at a high level;
at this time, the zener diode ZD1, the triode Q2 and the triode Q3 are all in a conducting state, and the control voltage Vout connected to the collector of the triode Q3 is pulled low, so that the subsequent circuit cannot be started;
and 4, step 4: with the increase of time, after the voltage Vbus rises to be higher than the starting threshold voltage Vth _ on, the controllable voltage stabilizing source Q1 is conducted, the output of the controllable voltage stabilizing source Q1 is at a low level which is not enough to enable the voltage stabilizing diode ZD1 to work, and the voltage stabilizing diode ZD1, the triode Q2 and the triode Q3 are all in a cut-off state;
the control voltage Vout of the collector of the triode Q3 is released, the control voltage Vout is connected with the soft start capacitor C3, and the voltage on the soft start capacitor C3 is gradually increased, so that the later-stage circuit is subjected to soft start;
and 5: the resistor R3 is a positive feedback resistor, after the voltage on the tested bus exceeds the starting threshold voltage Vth _ on, because the triode Q2 is cut off, the resistor R3 is not connected with the resistor R2 in parallel, the proportion of the voltage value of the reference electrode input into the controllable voltage-stabilizing source Q1 is increased, the voltage of the tested bus drops to a certain voltage near the starting threshold voltage Vth _ on, the controllable voltage-stabilizing source Q1 is still not cut off again, the capacitor C4 slows down the change speed of the controllable voltage-stabilizing source Q1, and the external DC-DC circuit is ensured to meet the stability requirement after the starting of the starting threshold voltage Vth _ on;
when the bus voltage is reduced, the off-threshold voltage Vth _ off of the off-bus voltage value of the external DC-DC stop work is determined by the resistor R1 and the resistor R2, and the calculation expression of the off-threshold voltage Vth _ off is as follows:
Vth_off×R2/(R1+R2)＝2.5V；
due to the existence of R3, the bus voltage is turned on and off, and a return difference voltage delta Vbus exists, and the calculation expression is as follows:
ΔVbus＝Vth_on-Vth_off。
preferably, in step 4, as the voltage on the bus under test rises, the voltage Vbus reaches the turn-on threshold voltage Vth _ on, and the calculation expression is:
Vth_on×(R2×R3/(R2+R3))/(R1+R2×R3/(R2+R3))＝2.5V。
preferably, the resistor R2 is selected as an initial value, the resistances of the resistor R1 and the resistor R3 are calculated according to the requirements of Vth _ on and Vth _ off, and the resistor R1 is obtained by selecting four equivalent resistors to be connected in series equivalently.
In this embodiment, the resistance value of the selected resistor R2 is selected to be 10-15K Ω, and Vcc can be set to be 12-15V; ZD1 may alternatively be 5-8V; the load resistor R4 of Q1 is set to satisfy the condition that when Q1 is turned on to 2.5V, the current flowing through R4 is 1mA, and may be selected to be 10K Ω. The R5 and C2 respectively select 100K Ω and 10uF (time constant 1S, about 100mS time to reach Vcc operating level) to meet the requirement of low-voltage fast power supply.
Example 3:
example 3 differs from example 1 in that: the controllable voltage-stabilizing source Q1 is replaced by a triode Q1, a voltage-stabilizing diode D3 is added behind a resistor R1, as shown in FIG. 3, the negative electrode of the voltage-stabilizing diode D3 is connected with the voltage Vbus through a resistor R1, the positive electrode of the voltage-stabilizing diode D3 is connected with the base electrode of a triode Q1, a resistor R2 is connected between the base electrode and the emitter electrode of the triode Q1, the emitter electrode of the triode Q1 is connected with the ground wire, a capacitor C1 is connected in parallel with the resistor R2, the collector electrode of the triode Q1 is connected with the negative electrode of a voltage-stabilizing diode ZD1, one end of a resistor R3 is connected with the base.
In embodiment 3, a transistor Q1 replaces a controllable voltage regulator Q1, and the principle is as follows:
step S1: when the external power supply Vin is powered on, the external power supply Vin supplies power to a capacitor C2 of a power supply Vcc node through a diode D1 and a resistor R5, and the power supply VCC quickly rises to a power supply voltage;
step S2: at this time, due to the startup delay of the preceding stage PFC circuit on the bus to be tested and the influence of the rise time of the voltage Vbus on the bus to be tested, the voltage Vbus is lower than the turn-on threshold voltage Vth _ on of the reference electrode of the triode Q1 at this time, that is, the input voltage of the reference electrode of the triode Q1 is lower than the internal reference voltage thereof, the triode Q1 is cut off, and the output thereof is at a high level;
at this time, the zener diode ZD1, the triode Q2 and the triode Q3 are all in a conducting state, and the control voltage Vout connected to the collector of the triode Q3 is pulled low, so that the subsequent circuit cannot be started;
step S3: as time increases, after the voltage Vbus rises to be higher than the turn-on threshold voltage Vth _ on, the transistor Q1 is turned on, the output thereof is at a low level which is not enough to make the zener diode ZD1 work, and the zener diode ZD1, the transistor Q2 and the transistor Q3 are all in a cut-off state;
the control voltage Vout of the collector of the triode Q3 is released, the control voltage Vout is connected with the soft start capacitor C3, and the voltage on the soft start capacitor C3 is gradually increased, so that the later-stage circuit is subjected to soft start;
step S4: the resistor R3 is a positive feedback resistor, after the voltage on the tested bus exceeds the starting threshold voltage Vth _ on, because the triode Q2 is cut off, the resistor R3 is no longer connected with the resistor R2 in parallel, the proportion of the voltage value of the reference electrode input to the triode Q1 is increased, the triode Q1 is still not cut off again after the voltage of the tested bus falls to a certain voltage near the starting threshold voltage Vth _ on, the capacitor C4 slows down the change speed of the triode Q1, and the external DC-DC circuit is ensured to meet the stability requirement after the starting of the starting threshold voltage Vth _ on.
In this embodiment, since the transistor Q1 is selected, the reference voltage when the operating state of the transistor Q1 is changed is 0.55-0.7V, and in this embodiment 3, it is necessary to redesign and select various parameter values such as R1, R2, and R3, so as to implement setting of the DC-DC input voltage range.
The invention relates to a working sequence control circuit in a two-stage conversion circuit and a method thereof, which solve the technical problem that whether a DC-DC circuit normally starts to work or not by collecting and comparing the bus voltage.
In the present invention, any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing steps of a custom logic function or process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the embodiments of the present invention.
The logic and/or steps represented in the flowcharts or otherwise described herein, e.g., an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.
It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.
It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.
In addition, functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (8)
1. A work sequence control circuit in a two-stage conversion circuit is characterized in that: the system comprises a power supply unit, a voltage detection unit, a time sequence control unit, a voltage return difference unit and a signal connection and soft start unit;
the time sequence control unit is respectively connected with the power supply unit, the voltage detection unit, the voltage return difference unit and the signal connection and soft start unit;
the voltage detection unit samples the voltage of the bus to be detected;
the time sequence control unit is used for generating a time sequence signal, and the signal connection and soft start unit outputs a control voltage Vout through the time sequence signal;
the voltage return difference unit is used for setting the working return difference voltage of the measured voltage.
2. The operation timing control circuit in a two-stage conversion circuit as claimed in claim 1, wherein: the time sequence control unit comprises a voltage stabilizing diode ZD2 and a capacitor C2, the power supply unit comprises a diode D1, a resistor R5 and a resistor R4, the anode of the diode D1 is connected with an external power supply Vin and one end of a cathode connecting resistor R5, the other end of the resistor R5 is connected with a power supply VCC, the cathode of the voltage stabilizing diode ZD2 is connected with the power supply VCC and the anode is connected with a ground wire, and the capacitor C2 is connected with the voltage stabilizing diode ZD2 in parallel.
3. The operation timing control circuit in a two-stage conversion circuit as claimed in claim 2, wherein: the voltage detection unit comprises a controllable voltage-stabilizing source Q1, a capacitor C4, a capacitor C1, a resistor R2 and a resistor R1, wherein a reference electrode of the controllable voltage-stabilizing source Q1 is connected with the tested bus through a resistor R1 and is used for collecting the voltage Vbus on the tested bus;
the reference electrode of the controllable voltage-stabilizing source Q1 is also connected with the ground wire through a resistor R2, and a capacitor C1 is connected with the resistor R2 in parallel;
the anode of the controllable voltage-stabilizing source Q1 is connected with the ground wire, and the cathode is connected with the reference electrode of the controllable voltage-stabilizing source Q1 through a resistor C4;
the cathode of the controllable voltage-stabilizing source Q1 is also connected with the power supply VCC through the resistor R4.
4. The operation timing control circuit in a two-stage conversion circuit according to claim 3, wherein: the signal connection and soft start unit comprises a triode Q2, a triode Q3, a zener diode ZD1 and a capacitor C3, wherein the emitting electrode of the triode Q2 is connected with the ground wire, and the base electrode of the triode Q2 is connected with the anode of the zener diode ZD 1;
an emitting electrode of the triode Q3 is connected with a ground wire, a collecting electrode is connected with the control voltage Vout, the capacitor C3 is connected between the emitting electrode and the collecting electrode of the triode Q3, a base electrode of the triode Q3 is connected with the anode of the voltage stabilizing diode ZD1, and the cathode of the voltage stabilizing diode ZD1 is connected with the cathode of the controllable voltage stabilizing source Q1.
5. The operation timing control circuit in a two-stage conversion circuit according to claim 4, wherein: the voltage return difference unit comprises a resistor R3, one end of a resistor R3 is connected with the reference electrode of the controllable voltage-stabilizing source Q1, and the other end of the resistor R3 is connected with the collector electrode of the triode Q2.
6. A working time sequence control method in a two-stage conversion circuit is characterized in that: the method comprises the following steps:
step 1: establishing a working sequence control circuit in the two-stage conversion circuit, wherein a control voltage Vout is connected with a control circuit enabling pin of a rear-stage circuit, the input voltage of the control circuit enabling pin of the rear-stage circuit is started at a high level, and the low level is not started;
step 2: when the external power supply Vin is powered on, the external power supply Vin supplies power to a capacitor C2 of a power supply Vcc node through a diode D1 and a resistor R5, and the power supply VCC quickly rises to a power supply voltage;
and step 3: at this time, due to the starting delay of a preceding stage PFC circuit on the tested bus and the influence of the rising time of the voltage Vbus on the tested bus, the voltage Vbus is lower than the starting threshold voltage Vth _ on of the reference electrode of the controllable voltage-stabilizing source Q1 at the moment, namely, the input voltage of the reference electrode of the controllable voltage-stabilizing source Q1 is smaller than the internal reference voltage thereof, the controllable voltage-stabilizing source Q1 is cut off, and the output thereof is at a high level;
at this time, the zener diode ZD1, the triode Q2 and the triode Q3 are all in a conducting state, and the control voltage Vout connected to the collector of the triode Q3 is pulled low, so that the subsequent circuit cannot be started;
and 4, step 4: with the increase of time, after the voltage Vbus rises to be higher than the starting threshold voltage Vth _ on, the controllable voltage stabilizing source Q1 is conducted, the output of the controllable voltage stabilizing source Q1 is at a low level which is not enough to enable the voltage stabilizing diode ZD1 to work, and the voltage stabilizing diode ZD1, the triode Q2 and the triode Q3 are all in a cut-off state;
the control voltage Vout of the collector of the triode Q3 is released, the control voltage Vout is connected with the soft start capacitor C3, and the voltage on the soft start capacitor C3 is gradually increased, so that the later-stage circuit is subjected to soft start;
and 5: the resistor R3 is a positive feedback resistor, after the voltage on the tested bus exceeds the starting threshold voltage Vth _ on, because the triode Q2 is cut off, the resistor R3 is not connected with the resistor R2 in parallel, the proportion of the voltage value of the reference electrode input into the controllable voltage-stabilizing source Q1 is increased, the voltage of the tested bus drops to a certain voltage near the starting threshold voltage Vth _ on, the controllable voltage-stabilizing source Q1 is still not cut off again, the capacitor C4 slows down the change speed of the controllable voltage-stabilizing source Q1, and the external DC-DC circuit is ensured to meet the stability requirement after the starting of the starting threshold voltage Vth _ on;
when the bus voltage is reduced, the off-threshold voltage Vth _ off of the off-bus voltage value of the external DC-DC stop work is determined by the resistor R1 and the resistor R2, and the calculation expression of the off-threshold voltage Vth _ off is as follows:
Vth_off×R2/(R1+R2)＝2.5V；
due to the existence of R3, the bus voltage is turned on and off, and a return difference voltage delta Vbus exists, and the calculation expression is as follows:
ΔVbus＝Vth_on-Vth_off。
7. the method of claim 6, wherein the method further comprises: in step 4, as the voltage on the bus to be tested rises, the voltage Vbus reaches the turn-on threshold voltage Vth _ on, and the calculation expression is:
Vth_on×(R2×R3/(R2+R3))/(R1+R2×R3/(R2+R3))＝2.5V。
8. the method of claim 6, wherein the method further comprises: selecting a resistor R2 as an initial value, calculating the resistance values of a resistor R1 and a resistor R3 according to the requirements of Vth _ on and Vth _ off, and selecting four equivalent resistors to be connected in series equivalently to obtain the resistor R1.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117460123A (en) * | 2023-12-26 | 2024-01-26 | 深圳莱福德科技股份有限公司 | Method for preventing no-load runaway of LED driving power supply |
Citations (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020179725A1 (en) * | 2001-05-31 | 2002-12-05 | Shearer Jon Douglas | Low noise solid-state thermostat |
| CN104539166A (en) * | 2014-12-16 | 2015-04-22 | 广州金升阳科技有限公司 | Biasing circuit used of self-excitation push-pull type converter |
| CN204442163U (en) * | 2015-04-09 | 2015-07-01 | 广东工业大学 | The quick active leadage circuit of AC-DC driver output filter capacitor |
| CN104968070A (en) * | 2015-03-18 | 2015-10-07 | 盐城工学院 | LED driving circuit |
| CN106452040A (en) * | 2016-10-20 | 2017-02-22 | 广州金升阳科技有限公司 | Starting circuit |
| CN106532629A (en) * | 2016-12-29 | 2017-03-22 | 电子科技大学 | Overcurrent protection circuit with self-recovery function |
| CN106558980A (en) * | 2016-11-29 | 2017-04-05 | 广州金升阳科技有限公司 | It is a kind of to enable control circuit |
| US20180048232A1 (en) * | 2016-08-09 | 2018-02-15 | California Institute Of Technology | Digital multiphase hysteretic point-of-load dc/dc converter |
| CN108233693A (en) * | 2018-02-26 | 2018-06-29 | 广州金升阳科技有限公司 | A kind of start-up circuit of ultralow input voltage |
| CN208046210U (en) * | 2018-04-09 | 2018-11-02 | 广州金升阳科技有限公司 | A kind of protection circuit against input over-voltage and the Switching Power Supply comprising the circuit |
| CN108964436A (en) * | 2017-05-27 | 2018-12-07 | 许继集团有限公司 | A kind of Switching Power Supply start-up circuit |
| CN208299427U (en) * | 2018-06-13 | 2018-12-28 | 深圳市易优电气有限公司 | Overvoltage crowbar and over-pressure safety device |
| CN109412117A (en) * | 2018-12-06 | 2019-03-01 | 广州金升阳科技有限公司 | A kind of protection circuit against input over-voltage |
| CN208691165U (en) * | 2018-03-22 | 2019-04-02 | 南阳师范学院 | A kind of passive braking circuit of standard |
| CN109742954A (en) * | 2019-01-07 | 2019-05-10 | 广州金升阳科技有限公司 | A kind of DC/DC converter |
| CN109980911A (en) * | 2019-03-29 | 2019-07-05 | 成都市易冲半导体有限公司 | A kind of soft starting circuit that can be adaptively selected and its method |
| CN110011652A (en) * | 2019-04-08 | 2019-07-12 | 北京承力电源有限公司 | A kind of Switching Power Supply at least second level starts sequential control circuit |
| CN209328495U (en) * | 2019-02-20 | 2019-08-30 | 广州视源电子科技股份有限公司 | A kind of soft starting circuit, backlight circuit, circuit board and display |
| CN209748516U (en) * | 2019-04-08 | 2019-12-06 | 北京承力电源有限公司 | Switch power supply at least two-stage starting sequential control circuit |
| CN210605505U (en) * | 2019-11-19 | 2020-05-22 | 常熟开关制造有限公司(原常熟开关厂） | DC voltage stabilizing circuit, power circuit and intelligent circuit breaker controller |
| CN210807208U (en) * | 2019-11-18 | 2020-06-19 | 合肥同智机电控制技术有限公司 | Auxiliary power supply switch circuit |
| CN210959221U (en) * | 2019-08-12 | 2020-07-07 | 国创新能源汽车智慧能源装备创新中心(江苏)有限公司 | Alternating-current charging stake PCB board heat radiation structure |
| CN211184384U (en) * | 2019-12-18 | 2020-08-04 | 江苏航天大为科技股份有限公司 | Power generator for fault self-fusing signal lamp |
-
2020
- 2020-11-27 CN CN202011364797.5A patent/CN112564471B/en active Active
Patent Citations (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020179725A1 (en) * | 2001-05-31 | 2002-12-05 | Shearer Jon Douglas | Low noise solid-state thermostat |
| CN104539166A (en) * | 2014-12-16 | 2015-04-22 | 广州金升阳科技有限公司 | Biasing circuit used of self-excitation push-pull type converter |
| CN104968070A (en) * | 2015-03-18 | 2015-10-07 | 盐城工学院 | LED driving circuit |
| CN204442163U (en) * | 2015-04-09 | 2015-07-01 | 广东工业大学 | The quick active leadage circuit of AC-DC driver output filter capacitor |
| US20180048232A1 (en) * | 2016-08-09 | 2018-02-15 | California Institute Of Technology | Digital multiphase hysteretic point-of-load dc/dc converter |
| CN106452040A (en) * | 2016-10-20 | 2017-02-22 | 广州金升阳科技有限公司 | Starting circuit |
| CN106558980A (en) * | 2016-11-29 | 2017-04-05 | 广州金升阳科技有限公司 | It is a kind of to enable control circuit |
| CN106532629A (en) * | 2016-12-29 | 2017-03-22 | 电子科技大学 | Overcurrent protection circuit with self-recovery function |
| CN108964436A (en) * | 2017-05-27 | 2018-12-07 | 许继集团有限公司 | A kind of Switching Power Supply start-up circuit |
| CN108233693A (en) * | 2018-02-26 | 2018-06-29 | 广州金升阳科技有限公司 | A kind of start-up circuit of ultralow input voltage |
| CN208691165U (en) * | 2018-03-22 | 2019-04-02 | 南阳师范学院 | A kind of passive braking circuit of standard |
| CN208046210U (en) * | 2018-04-09 | 2018-11-02 | 广州金升阳科技有限公司 | A kind of protection circuit against input over-voltage and the Switching Power Supply comprising the circuit |
| CN208299427U (en) * | 2018-06-13 | 2018-12-28 | 深圳市易优电气有限公司 | Overvoltage crowbar and over-pressure safety device |
| CN109412117A (en) * | 2018-12-06 | 2019-03-01 | 广州金升阳科技有限公司 | A kind of protection circuit against input over-voltage |
| CN109742954A (en) * | 2019-01-07 | 2019-05-10 | 广州金升阳科技有限公司 | A kind of DC/DC converter |
| CN209328495U (en) * | 2019-02-20 | 2019-08-30 | 广州视源电子科技股份有限公司 | A kind of soft starting circuit, backlight circuit, circuit board and display |
| CN109980911A (en) * | 2019-03-29 | 2019-07-05 | 成都市易冲半导体有限公司 | A kind of soft starting circuit that can be adaptively selected and its method |
| CN110011652A (en) * | 2019-04-08 | 2019-07-12 | 北京承力电源有限公司 | A kind of Switching Power Supply at least second level starts sequential control circuit |
| CN209748516U (en) * | 2019-04-08 | 2019-12-06 | 北京承力电源有限公司 | Switch power supply at least two-stage starting sequential control circuit |
| CN210959221U (en) * | 2019-08-12 | 2020-07-07 | 国创新能源汽车智慧能源装备创新中心(江苏)有限公司 | Alternating-current charging stake PCB board heat radiation structure |
| CN210807208U (en) * | 2019-11-18 | 2020-06-19 | 合肥同智机电控制技术有限公司 | Auxiliary power supply switch circuit |
| CN210605505U (en) * | 2019-11-19 | 2020-05-22 | 常熟开关制造有限公司(原常熟开关厂） | DC voltage stabilizing circuit, power circuit and intelligent circuit breaker controller |
| CN211184384U (en) * | 2019-12-18 | 2020-08-04 | 江苏航天大为科技股份有限公司 | Power generator for fault self-fusing signal lamp |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117460123A (en) * | 2023-12-26 | 2024-01-26 | 深圳莱福德科技股份有限公司 | Method for preventing no-load runaway of LED driving power supply |
| CN117460123B (en) * | 2023-12-26 | 2024-03-15 | 深圳莱福德科技股份有限公司 | Method for preventing no-load runaway of LED driving power supply |
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