CN205453479U

CN205453479U - Two many output driver of isolation systems

Info

Publication number: CN205453479U
Application number: CN201620130600.4U
Authority: CN
Inventors: 杨航; 刘凌; 倪骏康; 胡全龙
Original assignee: Second Affiliated Hospital School of Medicine of Xian Jiaotong University
Current assignee: Second Affiliated Hospital School of Medicine of Xian Jiaotong University
Priority date: 2016-02-19
Filing date: 2016-02-19
Publication date: 2016-08-10
Anticipated expiration: 2026-02-19

Abstract

The utility model discloses a two many output driver of isolation systems. Including control panel and drive plate. The control panel contains control panel power module and the minimum system module of TMS320F28335 type DSP singlechip, the drive plate contains drive plate power module, power module, drive signal spare module, direct drive module, transformer isolation drive module, optical coupling isolation drive module, digital potentiometer module, display module and load module. Compare with current drive circuit, the utility model discloses six kinds of combinations of three kinds of drive circuit structures of accessible and two kinds of devices of accuse type entirely reduce switching loss in order to satisfy the drive requirement under the different power indexs, the accessible the button in the minimum system or the drive signal of required range of acquisition of the slide rheostat on the drive signal spare module and frequency and grid resistance are in order to show improvement drive properties. This system is used for the power electronic field to solve the drive circuit structure determination, keeps apart mode selection and the design of grid resistance parameter.

Description

A kind of double isolation multi output drive system

Technical field

This utility model relates to field of power electronics one drive system, especially a kind of double isolation multi output drive systems.

Background technology

Drive circuit is the interface of control circuit and device for power switching, its design relation system effectiveness and safety, and irrational circuit parameter can cause high voltage spike to damage driving chip and switching tube.At present, the design of most drive circuits is often single only for a certain specific driven object design element parameter and isolation method；Single electronic power switch pipe is adapted only to certain power and voltage occasion, as MOSFET is only suitable for small-power and the most high pressure resistant, when driven object changes, it is impossible to ensure good driveability.It is capacitive that the grid of IGBT, MOSFET penetrate (or grid source) interpolar, the stray inductance of grid return is inevitable, without resistance, grid return can produce the strongest vibration under the excitation of driver drives pulse, therefore must eliminate grid vibration by series gate resistance, resistance have impact on grid in full-controlled switch device transient process and penetrates the parameters such as (or grid source) rising of voltage across poles, fall time, switching loss and collector current rate of change.All there is technology shortcoming in the aspects such as China's research to driving puts into from the beginning of the nearly more than ten years are the most progressively, driving module research and development integrated at power.

Utility model content

In order to overcome the deficiencies in the prior art, the purpose of this utility model is to provide double isolation multi output drive systems that one comprises three kinds of driving circuit structures, two kinds of isolation methods (light-coupled isolation and transformer isolation) and two kinds of all-controlling power electronics devices (MOSFET and IGBT).

The technical solution of the utility model is achieved in that

Including panel and driving plate；Panel comprises panel power module and TMS320F28335 type DSP single-chip minimum system module；Plate is driven to comprise driving plate power module, power model, driving signal spare module, directly drive module, transformer isolation to drive module, light-coupled isolation to drive module, digital regulation resistance module, display module and load blocks；The signal output port that drives of TMS320F28335 type DSP single-chip minimum system module and driving signal spare module directly drives module, light-coupled isolation to drive module and transformer isolation to drive the input of module to be connected with driving plate, directly driving module, light-coupled isolation to drive module and transformer isolation to drive the outfan of module to be connected with the input of power model, the outfan of power model is connected with the input of load blocks.

Power module comprises panel power module and drives plate power module, and described panel power module uses model to be the chip of TPS767D301, and its 5 and 6,11 and No. 12 pins connect the DC voltage of+5～+9V；Its 3 and 4,9 and No. 10 pin ground connection and respectively with a 0.1uF patch capacitor in parallel and a 10uF electrochemical capacitor between 5 and 6,11 and 12 pins；After its 17 and No. 18 pin output+3.3V DC voltages, 23 and No. 24 pin output+1.8V DC voltages connect a 0.1uF patch capacitor and a 10uF electrochemical capacitor, ground connection is for power decoupling；+ 3.3V DC voltage connects a 1K Ω resistance and a light emitting diode to show that TPS767D301 chip normally works；The DC voltage inlet side of+5～+9V uses on-off control break-make, and panel power module provides power supply for TMS320F28335 type DSP single-chip minimum system module.

Described driving plate power module uses model to be the chip of 78M05, its No. 1 pin ground connection；Its No. 2 pins connect+15V DC voltage a 0.33uF capacity earth of connecting；+ 5V DC voltage a 0.01uF capacity earth of connecting is exported after its No. 3 pin serial connection one 1mH inductance；+ 15V DC voltage ground connection of connecting after a 3K Ω resistance and a light emitting diode is to show that voltage is successfully accessed, and driving plate power module is to drive signal spare module, directly drive module, light-coupled isolation to drive module, transformer isolation to drive module and display module to provide power supply.

Described driving signal spare module uses model to be the chip of NE555, and its No. 8 pins and No. 3 pins connect a switch respectively and export with control chip work and pwm signal；Its No. 4 pin serial connection one 1K Ω resistance are connected with No. 7 pins with after 10K Ω slide rheostat；Its No. 2 are connected and a 4.7nF patch capacitor ground connection of connecting with No. 6 pins, are connected with No. 7 pins after another series connection one 20K Ω slide rheostat；Ground connection after its No. 5 pin serial connection one 10nF patch capacitors；Its No. 1 pin is directly grounded.

The resistance of described driving module is the digital regulation resistance of MCP410 by model, and its No. 1, No. 2 and No. 3 pins are connected with TMS320F28335 type DSP single-chip minimum system module；Its No. 8 pins connect+5V DC voltage；Its No. 4 pin ground connection, its No. 5, No. 6 and No. 7 pins pick out to use as the adjustable resistance of resistance.

Described direct driving module comprises the chip that model is IR2121, and its No. 1 pin connects+15V DC voltage；Its No. 8 pins connect 0.1uF patch capacitor and decouple for chip power；Its No. 2 pins are driving signal input；Ground connection after its No. 3 and No. 4 pins in parallel one 0.1uF patch capacitors；Its No. 5 and No. 6 pin ground connection；Its No. 7 pins are driving voltage outfan, are connected to resistance input；Owing to the high insulation resistance between switching tube grid source electrode and between grid emitter-base bandgap grading and thin dielectric layer easily cause device breakdown, therefore between grid emitter-base bandgap grading and a 10K Ω resistance is to discharge gate charge and to protect device.

Described light-coupled isolation drives module to comprise the optocoupler driving chip that model is TLP250；Its No. 1 and No. 4 pins unsettled；Its No. 2 pins are driving signal input, and a 2K Ω resistance of connecting before this pin is with current limliting；Its No. 3 pin ground connection；Its No. 6 are connected as driving voltage outfan with No. 7 pins, are connected to resistance input；Its No. 8 pins connect+15V DC voltage and a 0.1uF capacity earth of connecting decouples for chip power；For faster devices turn-off speed, access-9V DC voltage at No. 5 pins of TLP250 chip.

It is the direct driving chip of IR2121, pulse transformer and two 5V stabilivolts that described transformer isolation drives module to comprise model；No. 1 pin of IR2121 chip connects+15V DC voltage；Its No. 8 pins connect 0.1uF patch capacitor and decouple for chip power；Its No. 2 pins are driving signal input；Ground connection after its No. 3 and No. 4 pins in parallel one 0.1uF patch capacitors；Its No. 5 and No. 6 pin ground connection；Its No. 7 pins are driving voltage outfan, are connected to resistance input；Pulse transformer primary series capacitance plays the effect of isolated DC component, and series resistance, to absorb resonant energy, eliminates voltage oscillation；The transformer turn ratio selected is 1:1, by the Zener diode of two differential concatenations being connected in parallel on its both sides to play negative voltage clamper between grid and source electrode, and quickening switching tube turn-off speed；A 10K Ω resistance in parallel between grid source electrode.

Described display module be model be the chip of LCD1602, its signal input part 4～No. 16 pins are connected with TMS320F28335 type DSP single-chip minimum system.

The beneficial effects of the utility model are: can reduce switching loss by six kinds of combinations of three kinds of driving circuit structures and two kinds of wholly-controled device to meet the driving requirement under different capacity index；When driven object changes, needed for can being obtained by the slide rheostat on the button on single-chip minimum system or driving signal spare module, amplitude and the driving signal of frequency and grid resistance value are to significantly improve the driveability of system, thus obtain satisfied driving effect.This system determines for field of power electronics solution driving circuit structure, isolation method selects and resistance parameter designing.

Accompanying drawing explanation

Fig. 1 is this utility model system structure schematic diagram.

Fig. 2 is this utility model panel power module circuitry schematic diagram.

Fig. 3 is this utility model panel JTAG modular circuit schematic diagram.

Fig. 4 is that this utility model panel guides modular circuit schematic diagram.

Fig. 5 is that this utility model drives plate power module circuitry schematic diagram.

Fig. 6 is that this utility model drives power output plate modular circuit schematic diagram.

Fig. 7 is that this utility model drives plate to drive signal spare module circuit theory diagrams.

Fig. 8 is that this utility model drives plate display module circuit theory diagrams.

Fig. 9 is that this utility model drives plate directly to drive modular circuit schematic diagram.

Figure 10 is that this utility model drives board transformer isolation drive modular circuit schematic diagram.

Figure 11 is that this utility model drives plate light-coupled isolation to drive modular circuit schematic diagram.

Figure 12 is that this utility model drives plate digital regulation resistance modular circuit schematic diagram.

Detailed description of the invention

Below in conjunction with accompanying drawing, this utility model is described in further detail, every employing analog structure of the present utility model and similar change thereof, protection scope of the present invention all should be listed in.

As it is shown in figure 1, this utility model comprises panel and drives plate.Panel comprises panel power module (Fig. 2), JTAG module (Fig. 3), guides module (Fig. 4), TMS320F28335 chip, power filtering module, double plug-in unit pricking with needle module, reseting module and clock module etc.；Plate is driven to comprise driving plate power module (Fig. 5), power model (Fig. 6), driving signal spare module (Fig. 7), display module (Fig. 8), directly drive module (Fig. 9), transformer isolation to drive module (Figure 10), light-coupled isolation to drive module (Figure 11), digital regulation resistance module (Figure 12) and load blocks；The signal output part that drives of TMS320F28335 type DSP single-chip minimum system module and driving signal spare module directly drives module, light-coupled isolation to drive module and transformer isolation to drive the input of module to be connected with driving plate, directly driving module, light-coupled isolation to drive module and transformer isolation to drive the outfan of module to be connected with the input of power model, the outfan of power model is connected with the input of load blocks.

As in figure 2 it is shown, the high precision electro source chip that this utility model panel power module uses model to be TPS767D301 produces+3.3V and two kinds of voltages of+1.8V for DSP.Its 5 and 6,11 and No. 12 pins connect the DC voltage of+5～+9V；Its 3 and 4,9 and No. 10 pin ground connection and respectively with a 0.1uF patch capacitor in parallel and a 10uF electrochemical capacitor between 5 and 6,11 and 12 pins；After its 17 and No. 18 pin output+3.3V DC voltages, 23 and No. 24 pin output+1.8V DC voltages connect a 0.1uF patch capacitor and a 10uF electrochemical capacitor, ground connection is for power decoupling；+ 3.3V DC voltage connects a 1K Ω resistance and a light emitting diode to show that TPS767D301 chip normally works；The DC voltage inlet side of+5～+9V uses on-off control break-make.Panel power module provides power supply for TMS320F28335 type DSP single-chip minimum system module.Minimum system clock circuit module of the present utility model uses TMS320F28335 type DSP single-chip microcomputer external crystal oscillator, the quartz crystal of a 30MHz is connected between X1 and X2, system selects the PLL function of 5 frequencys multiplication by programming, can realize the maximum operating frequency (150MHz) of TMS320F28335.

As shown in Figure 3, this utility model panel JTAG module downloads the anti-interference of mouth in view of JTAG, at the TDI being connected with DSP, TMS, TCK, EMUO, EMU1 port is connected to power supply by the pull-up resistor of 4.7k Ω, the TRST pin pull down resistor ground connection by 4.7k Ω, and on its pin, add the shunt capacitance of 0.1 μ F respectively.

As shown in Figure 4, this utility model panel guides the vector meeting of restarting in module booting ROM again to perform to the incoming program of InitBoot function, its option includes: jump to Flash, jump to SARAM, jump to OTP, jump to XINTF or call from serial ports and guide to download routines a sheet.When equipment is restarted, after the equipment of execution initializes, bootstrap can check that the state of GPIO pin is to determine that user selects which kind of bootmode, physical circuit connection to refer to Fig. 4.

As it is shown in figure 5, this utility model drives plate power module to use model to be the chip of 78M05, its No. 1 pin ground connection；Its No. 2 pins connect+15V DC voltage a 0.33uF capacity earth of connecting；+ 5V DC voltage a 0.01uF capacity earth of connecting is exported after its No. 3 pin serial connection one 1mH inductance；+ 15V DC voltage connects after a 3K Ω resistance and a light emitting diode ground connection to show that voltage is successfully accessed.Drive plate power module for driving signal spare module, directly driving module, light-coupled isolation to drive module, transformer isolation to drive module and display module to provide power supply.

As shown in Figure 6, this utility model drives the MOSFET of power output plate module to use the IRFP4568PbF, IGBT of IR company to use the IKW25N120H3 of Infineon company；The drain electrode of MOSFET and the colelctor electrode series limiting resistor of IGBT are followed by+24V DC voltage；The source electrode of MOSFET and the grounded emitter of IGBT；The colelctor electrode of the drain electrode of MOSFET, grid, source electrode and IGBT, grid, emitter stage are drawn respectively for test and connect.

As it is shown in fig. 7, this utility model drives plate to drive signal spare module to use model to be the chip of NE555, its No. 8 pins and No. 3 pins connect a switch respectively and export with control chip work and pwm signal；Its No. 4 pin serial connection one 1K Ω resistance are connected with No. 7 pins with after 10K Ω slide rheostat；Its No. 2 are connected and a 4.7nF patch capacitor ground connection of connecting with No. 6 pins, are connected with No. 7 pins after another series connection one 20K Ω slide rheostat；Ground connection after its No. 5 pin serial connection one 10nF patch capacitors；Its No. 1 pin is directly grounded.The effect driving signal spare module is to make the amplitude of driving signal, frequency-adjustable.

As shown in Figure 8, this utility model drive plate display module be model be the chip of LCD1602, its signal input part (4～No. 16 pins) is connected with TMS320F28335 type DSP single-chip minimum system, in order to show when the amplitude of front wheel driving signal and frequency and grid resistance value.

The chip that model is IR2121 as it is shown in figure 9, this utility model drives plate directly to drive module to comprise, its No. 1 pin connects+15V DC voltage；Its No. 8 pins connect 0.1uF patch capacitor and decouple for chip power；Its No. 2 pins are driving signal input；Ground connection after its No. 3 and No. 4 pins in parallel one 0.1uF patch capacitors；Its No. 5 and No. 6 pin ground connection；Its No. 7 pins are driving voltage outfan, are connected to resistance input；Owing to the high insulation resistance between switching tube grid source electrode and between grid emitter-base bandgap grading and thin dielectric layer easily cause device breakdown, therefore between grid emitter-base bandgap grading and a 10K Ω resistance is to discharge gate charge and to protect device.

As shown in Figure 10, this utility model drives plate light-coupled isolation to drive module to comprise the optocoupler driving chip that model is TLP250；Its No. 1 and No. 4 pins unsettled；Its No. 2 pins are driving signal input, and the input current brought by PWM for reduction, a 2K Ω resistance of connecting before this pin is with current limliting；Its No. 3 pin ground connection；Its No. 6 are connected as driving voltage outfan with No. 7 pins, are connected to resistance input；Its No. 8 pins connect+15V DC voltage and a 0.1uF capacity earth of connecting decouples for chip power；For faster devices turn-off speed, access-9V DC voltage at No. 5 pins of TLP250 chip.

As shown in figure 11, this utility model drives board transformer isolation drive module to comprise model is the direct driving chip of IR2121, pulse transformer and two 5V stabilivolts；No. 1 pin of IR2121 chip connects+15V DC voltage；Its No. 8 pins connect 0.1uF patch capacitor and decouple for chip power；Its No. 2 pins are driving signal input；Ground connection after its No. 3 and No. 4 pins in parallel one 0.1uF patch capacitors；Its No. 5 and No. 6 pin ground connection；Its No. 7 pins are driving voltage outfan, are connected to resistance input；Pulse transformer primary series capacitance plays the effect of isolated DC component, and series resistance, to absorb resonant energy, eliminates voltage oscillation；The transformer turn ratio selected is 1:1, by the Zener diode of two differential concatenations being connected in parallel on its both sides to play negative voltage clamper between grid and source electrode, and quickening switching tube turn-off speed；Between grid source electrode, a 10K Ω resistance in parallel is with protection grid and switching device.

As shown in figure 12, this utility model drives the resistance of module to be the digital regulation resistance of MCP410 by model, and its No. 1, No. 2 and No. 3 pins are connected with TMS320F28335 type DSP single-chip minimum system module；Its No. 8 pins connect+5V DC voltage；Its No. 4 pin ground connection, its No. 5, No. 6 and No. 7 pins pick out to use as the adjustable resistance of resistance.

Before system work, this utility model is first by 1,3 or 2, the 3 of two ends access power module (Fig. 6) P7 of load, reselection directly drives module (Fig. 9), transformer isolation to drive module (Figure 10) and light-coupled isolation to drive the one (in P2, P3, P4, is connected) in module (Figure 11) with in P5, P6 corresponding pin, can be by six kinds of combinations of three kinds of driving circuit structures and two kinds of wholly-controled device to meet the driving requirement under different capacity index.Tri-pins of the P11 of digital regulation resistance module (Figure 12) are connected with panel, the 1 of P12,2 or 2,3 drive the P9 in module (Figure 10) or light-coupled isolation to drive the 1 of P10,2 in module (Figure 11) to be connected with the P8 directly driven in module (Fig. 9), transformer isolation to be adjusted resistance by the monolithic processor controlled digital regulation resistance of TMS320F28335 type DSP (Figure 12) with realization.Each pin of display module (Fig. 8) is corresponding with panel TMS320F28335 type DSP single-chip microcomputer to be connected to show the amplitude and frequency and grid resistance value working as front wheel driving signal.When not having panel, available button S1 and S2 driving signal spare module (Fig. 7) opens this module, and by adjusting slide rheostat Radj1 and Radj2 to realize the adjustment of drive signal amplitude and frequency.

During work, if selecting directly to drive module (Fig. 9), TMS320F28335 type DSP single-chip minimum system or No. 2 pins driving the driving signal of signal spare module (Fig. 7) to pass through U1 chip input, driving voltage is added in the grid source electrode two ends of MOSFET or the grid emitter-base bandgap grading two ends of IGBT by resistance by output signal, to drive MOSFET or IGBT.If selecting transformer isolation to drive module (Figure 10), TMS320F28335 type DSP single-chip minimum system or No. 2 pins driving the driving signal of signal spare module (Fig. 7) to pass through U2 chip input, driving voltage is added in the grid source electrode two ends of MOSFET or the grid emitter-base bandgap grading two ends of IGBT by resistance by output signal, to drive MOSFET or IGBT.If selecting light-coupled isolation to drive module (Figure 11), TMS320F28335 type DSP single-chip minimum system or No. 2 pins driving the driving signal of signal spare module (Fig. 7) to pass through U3 chip input, driving voltage is added in the grid source electrode two ends of MOSFET or the grid emitter-base bandgap grading two ends of IGBT by resistance by output signal, to drive MOSFET or IGBT.

Claims

1. double isolation multi output drive systems, including panel and driving plate；Panel comprises panel power module and TMS320F28335 type DSP single-chip minimum system module；Plate is driven to comprise driving plate power module, power model, driving signal spare module, directly drive module, transformer isolation to drive module, light-coupled isolation to drive module, digital regulation resistance module, display module and load blocks；It is characterized in that, the signal output port that drives of TMS320F28335 type DSP single-chip minimum system module and driving signal spare module directly drives module, light-coupled isolation to drive module and transformer isolation to drive the input of module to be connected with driving plate, directly driving module, light-coupled isolation to drive module and transformer isolation to drive the outfan of module to be connected with the input of power model, the outfan of power model is connected with the input of load blocks.

Double isolation multi output drive system the most according to claim 1, it is characterized in that, power module comprises panel power module and drives plate power module, described panel power module uses model to be the chip of TPS767D301, and its 5 and 6,11 and No. 12 pins connect the DC voltage of+5～+9V；Its 3 and 4,9 and No. 10 pin ground connection and respectively with a 0.1uF patch capacitor in parallel and a 10uF electrochemical capacitor between 5 and 6,11 and 12 pins；After its 17 and No. 18 pin output+3.3V DC voltages, 23 and No. 24 pin output+1.8V DC voltages connect a 0.1uF patch capacitor and a 10uF electrochemical capacitor, ground connection is for power decoupling；+ 3.3V DC voltage connects a 1K Ω resistance and a light emitting diode to show that TPS767D301 chip normally works；The DC voltage inlet side of+5～+9V uses on-off control break-make, and panel power module provides power supply for TMS320F28335 type DSP single-chip minimum system module.

Double isolation multi output drive system the most according to claim 2, it is characterised in that described driving plate power module uses model to be the chip of 78M05, its No. 1 pin ground connection；Its No. 2 pins connect+15V DC voltage a 0.33uF capacity earth of connecting；+ 5V DC voltage a 0.01uF capacity earth of connecting is exported after its No. 3 pin serial connection one 1mH inductance；+ 15V DC voltage ground connection of connecting after a 3K Ω resistance and a light emitting diode is to show that voltage is successfully accessed, and driving plate power module is to drive signal spare module, directly drive module, light-coupled isolation to drive module, transformer isolation to drive module and display module to provide power supply.

Double isolation multi output drive system the most according to claim 2, it is characterised in that described driving signal spare module uses model to be the chip of NE555, its No. 8 pins and No. 3 pins connect a switch respectively and export with control chip work and pwm signal；Its No. 4 pin serial connection one 1K Ω resistance are connected with No. 7 pins with after 10K Ω slide rheostat；Its No. 2 are connected and a 4.7nF patch capacitor ground connection of connecting with No. 6 pins, are connected with No. 7 pins after another series connection one 20K Ω slide rheostat；Ground connection after its No. 5 pin serial connection one 10nF patch capacitors；Its No. 1 pin is directly grounded.

Double isolation multi output drive system the most according to claim 1, it is characterized in that, the resistance of described driving module is the digital regulation resistance of MCP410 by model, and its No. 1, No. 2 and No. 3 pins are connected with TMS320F28335 type DSP single-chip minimum system module；Its No. 8 pins connect+5V DC voltage；Its No. 4 pin ground connection, its No. 5, No. 6 and No. 7 pins pick out to use as the adjustable resistance of resistance.

Double isolation multi output drive system the most according to claim 1, it is characterised in that described direct driving module comprises the chip that model is IR2121, and its No. 1 pin connects+15V DC voltage；Its No. 8 pins connect 0.1uF patch capacitor and decouple for chip power；Its No. 2 pins are driving signal input；Ground connection after its No. 3 and No. 4 pins in parallel one 0.1uF patch capacitors；Its No. 5 and No. 6 pin ground connection；Its No. 7 pins are driving voltage outfan, are connected to resistance input；Owing to the high insulation resistance between switching tube grid source electrode and between grid emitter-base bandgap grading and thin dielectric layer easily cause device breakdown, therefore between grid emitter-base bandgap grading and a 10K Ω resistance is to discharge gate charge and to protect device.

Double isolation multi output drive system the most according to claim 1, it is characterised in that described light-coupled isolation drives module to comprise the optocoupler driving chip that model is TLP250；Its No. 1 and No. 4 pins unsettled；Its No. 2 pins are driving signal input, and a 2K Ω resistance of connecting before this pin is with current limliting；Its No. 3 pin ground connection；Its No. 6 are connected as driving voltage outfan with No. 7 pins, are connected to resistance input；Its No. 8 pins connect+15V DC voltage and a 0.1uF capacity earth of connecting decouples for chip power；For faster devices turn-off speed, access-9V DC voltage at No. 5 pins of TLP250 chip.

Double isolation multi output drive system the most according to claim 1, it is characterised in that it is the direct driving chip of IR2121, pulse transformer and two 5V stabilivolts that described transformer isolation drives module to comprise model；No. 1 pin of IR2121 chip connects+15V DC voltage；Its No. 8 pins connect 0.1uF patch capacitor and decouple for chip power；Its No. 2 pins are driving signal input；Ground connection after its No. 3 and No. 4 pins in parallel one 0.1uF patch capacitors；Its No. 5 and No. 6 pin ground connection；Its No. 7 pins are driving voltage outfan, are connected to resistance input；Pulse transformer primary series capacitance plays the effect of isolated DC component, and series resistance, to absorb resonant energy, eliminates voltage oscillation；The transformer turn ratio selected is 1:1, by the Zener diode of two differential concatenations being connected in parallel on its both sides to play negative voltage clamper between grid and source electrode, and quickening switching tube turn-off speed；A 10K Ω resistance in parallel between grid source electrode.

Double isolation multi output drive system the most according to claim 1, it is characterised in that described display module be model be the chip of LCD1602, its signal input part 4～No. 16 pins are connected with TMS320F28335 type DSP single-chip minimum system.