CN201355875Y

CN201355875Y - Electromagnetic oven circuit based on SoC chip

Info

Publication number: CN201355875Y
Application number: CNU2008202349801U
Authority: CN
Inventors: 丘守庆; 许申生; 刘春光; 李鹏; 陈劲锋
Original assignee: Shenzhen CHK Technology Co Ltd
Current assignee: Shenzhen CHK Technology Co Ltd
Priority date: 2008-12-12
Filing date: 2008-12-12
Publication date: 2009-12-02
Anticipated expiration: 2018-12-12

Abstract

The utility model relates to an electromagnetic oven circuit based on an SoC chip, which comprises a power inverter circuit and a CHK-S008 type SoC chip. The chip is internally integrated with a CPU, a comparator, an operational amplifier, an A/D converter and an IGBT drive and control module; a feedback simulation type IGBT drive comprises a drive and control module, a comparator, an external drive and an external feedback circuit which is connected between the output of the drive and control module and the in-phase input end of the comparator; the output of the comparator is connected with a feedback end of the drive and control module; and the external drive is connected between the output of the drive and control module and the input of the power inverter circuit to drive the power inverter circuit to work. A pulse signal is fed back to the inside of the chip by the external feedback circuit and corrects the IGBT drive waveform, optimize the waveform of the pulse signal and improve the working efficiency; and meanwhile, the external feedback circuit can generate simulation action to the weak condition of synchronous signals, and avoid the synchronous signals failing when the commercial power is lower.

Description

Electromagnetic oven circuit based on the SoC chip

Technical field

The utility model belongs to the electromagentic furnace technology field with the electric energy heating, especially a kind of electromagnetic oven circuit based on SoC (System on a Chip) chip.

Background technology

At present; main flow family expenses electromagnetic oven application circuit; generally be discrete elements such as employing four comparators or dual comparator and many resistance, electric capacity, diode, triode; circuit such as formation is synchronous, resonance, driving, current surge protection; cooperate MCU control, realize main resonant circuit and various basic defencive function.The shortcoming of existing sort circuit is: number of elements is many, and the fault point is many, produces, maintenance difficulty is big, whole cost height

Most electromagnetic ovens all produce the system synchronization signal by the IGBT source voltage and the direct voltage at sampling LC resonant tank two ends by a comparator comparison process, but when line voltage is low, sampled signal is very faint, causes comparator not overturn easily, sync fail.

Summary of the invention

Be the above-mentioned defective of avoiding existing electromagentic furnace technology to exist; the utility model provides a kind of electromagnetic oven circuit based on the SoC chip; integrated CPU in its SoC chip, some comparators, operational amplifier and by the IGBT drive control module of CPU control; and dispose the protective circuit of multiple optimal design; so that the electromagnetic oven functional reliability improves, production cost reduces.

Electromagnetic oven circuit based on the SoC chip of the present utility model comprises: rectifier bridge, filter, by power inversion circuit and control unit that IGBT and LC resonant tank are formed is characterized in that:

Control unit adopts CHK-S008 type SoC chip, the IGBT drive control module that is integrated with CPU, the some comparators that are connected with the respective input of CPU respectively, operational amplifier, an A/D converter in this SoC chip slapper and is connected in the output of CPU; Further comprise:

One feedback excitation formula IGBT driver, this IGBT driver comprises the IGBT drive control module in the described SoC chip slapper, first comparator, external drive circuit, and be connected to external feedback circuit between the described IGBT drive control module output and the first comparator in-phase input end, the feedback end of the output termination IGBT drive control module of first comparator, described external drive circuit is connected between the input of the output of described IGBT drive control module and power inversion circuit, and the output pulse signal of IGBT drive control module is amplified the power inversion circuit work that promotes.

The utility model further comprises a synchronous signal deteching circuit, this synchronization signal detection circuit comprise first comparator in the described SoC chip slapper, be connected in the synchronizing signal sample circuit of first comparator input terminal and be connected in described IGBT drive control module output with the first comparator in-phase input end between described external feedback circuit, this external feedback circuit is fed back the in-phase input end of pulse signal to the first comparator that described IGBT drive control module exports.

An interval stores the correcting current parameter in the built-in memory in the described CHK-S008 type SoC chip slapper, this memory, the power of calibration electromagnetic oven when being used for CPU operation calibration procedure.

The utility model electromagnetic oven circuit adopts the SoC chip technology, this SoC built-in chip type the CPU core control technology, brought into play frequency stabilization, power output management and control system signal initiatively, be not vulnerable to the advantage of external disturbance; The chip integration height, the peripheral applications circuit is simple, greatly reduces production, maintenance difficulty and cost.

It adopts the feedback excitation formula IGBT drive circuit of being made up of IGBT drive control module, external drive circuit and external feedback circuit etc. in the SoC chip slapper, IGBT drive control module output pulse signal feeds back to chip internal through external feedback circuit the IGBT drive waveforms is revised, optimize pulse signal waveform, increase work efficiency; Can produce incentive action to the faint situation of synchronizing signal by external feedback circuit simultaneously, avoid synchronizing signal when civil power is low, to lose efficacy.

Description of drawings

Fig. 1 is a theory diagram of the present utility model;

Fig. 2 is the embodiment circuit diagram;

The CHK-008 type SoC chip internal circuit diagram that Fig. 3 adopts for Fig. 2 embodiment.

Embodiment

Below in conjunction with embodiment the utility model is further specified

With reference to Fig. 1-3, electromagnetic oven circuit mainly comprises: rectifier bridge 1, filter 2, power inversion circuit 4 and the control unit 8 be made up of IGBT and LC resonant tank.Also be provided with current sampling circuit 3 in control unit 8 outsides, detect the voltage detecting circuit 9 of the voltage signal of input ac power, synchronized sampling circuit 5, external drive circuit 6 and external feedback circuit 7 or the like.

Control unit 8 adopts CHK-S008 type SoC chip shown in Figure 3, be integrated with CPU in this SoC chip slapper, four comparator C P0-CP3 that are connected with the respective input of CPU respectively, operational amplifier OP, A/D converter and the IGBT drive control module that is connected in the PPG signal output part of CPU.Also integrated one is used for other MCU or display driver chip communication data communication module, reaches memory etc. in the CHK-S008 type SoC chip slapper.

Wherein, an interval stores the correcting current parameter in the memory in the CHK-S008 type SoC chip slapper, the power of calibration electromagnetic oven when being used for CPU operation calibration procedure.Dispose the memory block that is used for storage products information in the described memory, can store the electromagnetic oven product information in this memory block, as: information such as product bar code, supplier number, serial number, date of manufacture.By button operation, on charactron or LED, show product information, can strengthen the information privacy effect, increase the counterfeit difficulty of product greatly.CHK-S008 type SoC chip adopts the 16PIN encapsulation.

IGBT drive control module in the described SoC chip slapper, comparator C P0, external drive circuit 6 and be connected in comparator C P0 in-phase input end and IGBT drive control module output between external feedback circuit 7 form feedback excitation formula IGBT drivers, the feedback end of the output termination IGBT drive control module of comparator C P0, external drive circuit 6 is connected between the output of described IGBT pre-driver module and the input of power inversion circuit 4 (being the grid of IGBT), and the output pulse signal of IGBT pre-driver module is amplified to promote power inversion circuit work.

Comparator C P0 in the described SoC chip slapper, synchronized sampling circuit 5 and outside feedback circuit 7 are formed synchronization signal detection circuit, this external feedback circuit 7 connects between the in-phase input end and IGBT drive control module output of comparator C P0, and this external feedback circuit is fed back the in-phase input end of the pulse signal of described IGBT drive control module output to comparator C P0.

Among embodiment Fig. 2, rectifier bridge 1, filter 2 and power inversion circuit 4 can adopt custom circuit, power inversion circuit 4 is made up of IGBT1 and LC resonant tank, the LC resonant tank is connected between the output of the source electrode of IGBT and filter, resonant inductance is arranged in the heating plate of electromagnetic oven, produce high-frequency alternating magnetic field during work on resonance coil, this high-frequency alternating magnetic field produces eddy current by the irony cooker and is converted to heat energy.

Feedback excitation formula IGBT driver comprises: the IGBT drive control module in the CHK-S008 type SoC chip slapper, comparator C P0, external drive circuit 6 and the external feedback circuit 7 that is composed in series by resistance R 9 and capacitor C 9, external feedback circuit 7 is connected between the in-phase input end (15Pin) of IGBT drive control module output (3Pin) and comparator C P0, the feedback end of the output termination IGBT drive control module of comparator C P0, the pulse signal of IGBT drive control module output feeds back to IGBT drive control module inside by external feedback circuit 7 and comparator C P0 the IGBT drive waveforms is revised, optimize pulse signal waveform, increase work efficiency.External drive circuit 6 is connected between the IGBT grid of the output of described IGBT drive control module and power inversion circuit 4, and the output pulse signal of IGBT pre-driver module is amplified to promote power inversion circuit work.

External drive circuit 6 is by triode Q1, Q2, Q3, reach resistance R 13, R14 composition, the Q1 collector electrode connects power positive end by R14, base stage connects power positive end by R13, and the base stage of Q2, Q3 connects the Q4 collector electrode, and the Q2 collector electrode connects power positive end, the collector electrode of Q3 and the grounded emitter of Q1, the emitter of Q2, Q3 connects as output, and this output connects the IGBT tube grid by current limliting R16, and the base stage of Q4 meets the IGBT driver module output 3Pin in the described SoC chip slapper.

Synchronization signal detection circuit comprises comparator C P0, synchronized sampling circuit 5 that is connected with comparator C P0 in the described SoC chip slapper and the external feedback circuit 7 that is composed in series by resistance R 9 and capacitor C 9, and this external feedback circuit connects between the in-phase input end and IGBT drive control module output of comparator C P0.

Synchronized sampling circuit 5 comprises resistance R 4, R5, R6 series arm, and this series arm is connected to the IGBT source electrode, is used for gathering the IGBT source voltage; And resistance R 4, R5 series arm, this series arm are used for gathering the direct voltage of LC resonant tank front end as benchmark.During the electromagnetism heating, synchronous sampling signal enters comparator C P0 and relatively produces synchronizing signal and offer CPU, when line voltage is low, comparator C P0 two input end signals are very faint, because of there is Offset in comparator, cause comparator not overturn this moment easily, sync fail, and the signal that the IGBT drive control module produces in the sheet of described SoC chip is stronger, process R9, C9 feedback effect are to comparator C P0 in-phase input end, can produce incentive action to the faint situation of synchronizing signal, avoid synchronizing signal when civil power is low, to lose efficacy.

Diode D1, D2, the divider resistance R17, the R18 that are connected with the D2 negative pole with diode D1, and the conventional voltage detecting circuit 9 formed such as capacitor C 22, diode D1, D2 positive pole connect rectifier bridge respectively and exchange incoming line, and voltage detecting circuit 9 outputs meet the input 7Pin of SoC chip.

The constantan wire resistance R K1 and the resistance R 8 etc. that are connected between rectifier bridge and the IGBT drain electrode constitute current sampling circuit 3, current sampling circuit 3 outputs meet the input 13Pin of described SoC chip, and the operational amplifier OP in this current sampling circuit 3 and the described SoC chip forms current detection circuit.The voltage detection signal of the current signal of current detection circuit output and voltage detecting circuit 9 outputs is imported the CPU rated output after the A/D converter conversion in sheet.

Comparator C P1 in the described SoC chip slapper and above-mentioned resistance R 4 as synchronized sampling circuit 5, R5, R6 series arm are formed a conventional IGBT recoil high-pressure limit circuit, resistance R 5, R6 common port meet the 14Pin of SoC chip to the comparator C P1 in-phase input end that is connected with CPU by resistance R 7, appropriateness is turned down power output when recording the recoil high pressure above set point.

Comparator C P2 in the described SoC chip slapper and outside surge voltage sample circuit can be formed the voltage surge testing circuit; comparator C P3 in the described SoC chip slapper and outside surge current sample circuit can be formed the current surge testing circuit, and then provide voltage or current surge protection by CPU and/or IGBT drive control module to the electromagnetic oven system.

Claims

1, a kind of electromagnetic oven circuit based on the SoC chip comprises rectifier bridge, filter, by power inversion circuit and control unit that IGBT and LC resonant tank are formed, it is characterized in that:

Control unit adopts CHK-S008 type SoC chip, the IGBT drive control module that is integrated with CPU, the some comparators that are connected with the respective input of CPU respectively, operational amplifier, an A/D converter in this SoC chip slapper and is connected in the output of CPU;

Further comprise:

One feedback excitation formula IGBT driver, this IGBT driver comprise IGBT drive control module, first comparator, the external drive circuit in the described SoC chip slapper and be connected to described IGBT drive control module output and the first comparator in-phase input end between external feedback circuit, the feedback end of the output termination IGBT drive control module of first comparator, described external drive circuit is connected between the input of the output of described IGBT drive control module and power inversion circuit, to promote power inversion circuit work.

2, according to the electromagnetic oven circuit of claim 1, it is characterized in that: further comprise a synchronous signal deteching circuit, this synchronization signal detection circuit comprise first comparator in the described SoC chip slapper, be connected in the synchronizing signal sample circuit of first comparator input terminal and be connected in described IGBT drive control module output with the first comparator in-phase input end between described external feedback circuit, this external feedback circuit is fed back the in-phase input end of pulse signal to the first comparator that described IGBT drive control module exports.

3, according to the electromagnetic oven circuit of claim 1, it is characterized in that: an interval stores the correcting current parameter in described CHK-S008 type SoC built-in chip type one memory, this memory, the power of calibration electromagnetic oven when being used for CPU operation calibration procedure.

4, according to the electromagnetic oven circuit of claim 3, it is characterized in that: be provided with the product information memory block that is used to store the electromagnetic oven product information in the described memory.

5, according to the electromagnetic oven circuit of claim 1 or 2 or 3, it is characterized in that: an also integrated communication module in the described CHK-008 type SoC chip slapper is used for and other CPU or display driver chip swap data.

6, electromagnetic oven circuit according to claim 1 or 2, it is characterized in that further comprising: described external drive circuit is by triode Q1, Q2, Q3, and resistance R 13, R14 forms, triode Q1 collector electrode connects power positive end by R14, base stage connects power positive end by R13, triode Q2, the base stage of Q3 connects triode Q4 collector electrode, triode Q2 collector electrode connects power positive end, the grounded emitter of the collector electrode of triode Q3 and triode Q1, triode Q2, the emitter of Q3 connects as output, this output termination IGBT grid, the base stage of triode Q4 connects the IGBT pre-driver module output in the described SoC chip slapper.

7, according to the electromagnetic oven circuit of claim 1 or 2, it is characterized in that: described external feedback circuit is composed in series by resistance R 9 and capacitor C 9.

8, according to the electromagnetic oven circuit of claim 1 or 2, it is characterized in that: described CHK-S008 type SoC chip adopts the 16PIN encapsulation.