CN202268797U - Circuit for improving performance of isolated driving circuit - Google Patents

Abstract

Translated fromChinese

一种改善隔离驱动电路性能的电路，包括驱动变压器B1及其原边的隔直电容C1、缓冲电阻R1和电阻R2、功率开关管，它还包括加速电容C2、在线取电电路；加速功率开关管开通及关断的电路；所述隔直电容C1接收的信号到达驱动变压器B1的次级后经过加速电容C2和缓冲电阻R1并联后的电路及电阻R2后，使信号加速且完整的进入所述的加速功率开关管开通及关断的电路而控制功率开关管快速的开通及关断。本实用新型通过对传统电路的改进，使得功率开关管的GS之间，能得到一个很好的单极性且幅度不随占空比变化的驱动脉冲。从而使得隔离驱动线路能够更好的适应更高效率，更稳定的现代各种开关电源及其他电子线路频率更高，体积更小，功率密度更大的要求。

A circuit for improving the performance of an isolated drive circuit, including a drive transformer B1 and a DC blocking capacitor C1 on its primary side, a snubber resistor R1 and a resistor R2, and a power switch tube. It also includes an acceleration capacitor C2 and an online power-fetching circuit; an acceleration power switch After the signal received by the DC blocking capacitor C1 reaches the secondary side of the drive transformer B1, it passes through the circuit in which the acceleration capacitor C2 and the buffer resistor R1 are connected in parallel and the resistor R2, so that the signal accelerates and completely enters the circuit. The circuit for accelerating the turn-on and turn-off of the power switch tube described above is used to control the fast turn-on and turn-off of the power switch tube. The utility model improves the traditional circuit, so that the GS of the power switch tube can obtain a good unipolar driving pulse whose amplitude does not vary with the duty cycle. As a result, the isolated drive circuit can better adapt to the requirements of higher efficiency and more stable modern various switching power supplies and other electronic circuits with higher frequency, smaller volume and higher power density.

Description

A kind of circuit that improves the isolated drive circuit performance

Technical field

The utility model relates to a kind of circuit that improves needs with the drive circuit performance of the power switch pipe of transformer isolation.

Background technology

At present, traditional transformer isolation drive circuit has exposed considerable problem in practice process, comprise misleading, and the efficiency losses that the driving force deficiency is brought is big, and the reverse breakdown power switch pipe responds soon inadequately, can not be suitable for higher frequency etc.Traditional isolated drive circuit figure sees accompanying drawing 2.

The utility model content

For overcoming the defective of prior art; The utility model is on the basis of original circuit; Reach desirable effect through increasing less components and parts, make between the GS of power switch pipe, can obtain a good unipolarity and amplitude not with the driving pulse of change in duty cycle.

The purpose of the utility model is achieved in that a kind of circuit that improves the isolated drive circuit performance; Comprise capacitance C1, buffer resistance R1 and resistance R 2, the power switch pipe Q3 on driving transformer B1 and former limit thereof, it also comprises speed-up capacitor C2, online power-supply circuit; The circuit that the accelerating power switching tube is opened and turn-offed; The signal that said capacitance C1 receives arrives behind driving transformer B1 secondary through behind the circuit and resistance R 2 after speed-up capacitor C2 and 1 parallel connection of buffering resistance R, makes the circuit that signal quickens and the complete described accelerating power switching tube of entering is opened and turn-offed and power controlling switching tube Q3 opens fast and turn-offs.

Described online power-supply circuit is made up of diode D1 and capacitor C 3; The anode of this diode D1 and an end of capacitor C 3 connect all that the accelerating power switching tube is opened and the feeder ear of breaking circuit; And the source electrode of the said power switch pipe of another termination of this capacitor C 3, the negative electrode of this diode D1 connects the signal input part of the circuit that said accelerating power switching tube opens and turn-off.

The totem structure that the circuit that described accelerating power switching tube is opened and turn-offed is made up of triode Q1 and Q2.

The capacitance C1 of the utility model makes the former limit of driving transformer winding reset with voltage very stably, and the output waveform of drive circuit does not have spine and vibration; Transmission of acceleration drive signal and the buffer circuit be made up of buffer resistance R1 and speed-up capacitor C2 make the secondary signal of driving transformer can reach the circuit of back complete and fast and don't can cause damage to the circuit of back, the online power taking circuit of being made up of diode D1 and capacitor C 3; Totem power supply for the back; Thereby do not need external power source, simplified circuit, capacitor C 3 has also played the effect of filtering interference signal simultaneously; Prevent that power switch pipe Q3 from misleading; By the totem structure that Q1 and Q2 form, accelerating power switching tube Q3 opens and closes closed procedure, thereby has reduced opening and turn-off power loss of power switch pipe Q3; Improved the whole efficiency of driver circuit; Also make this circuit can be operated in higher frequency, serve as the effect that prevents power switch pipe Q3 reverse breakdown by diode D2, the reverse voltage that makes power switch pipe Q3 bear is clamped down on about 0.7V.

The utility model is through through to the improvement of traditional circuit, makes between the GS of power switch pipe, can obtain a good unipolarity and amplitude not with the driving pulse of change in duty cycle.Thereby make the isolation drive circuit can better adapt to more high efficiency, more stable modern various Switching Power Supplies and other electronic circuit frequencies are higher, and volume is littler, power density bigger requirement.

Description of drawings

Fig. 1 is the circuit theory diagrams of the utility model;

Fig. 2 is traditional isolated drive circuit figure.

Embodiment

Below in conjunction with accompanying drawing the utility model and beneficial effect thereof are done further detailed explanation.With reference to figure 1, a kind of circuit that improves the isolated drive circuit performance comprises that it also comprises speed-up capacitor C2, online power-supply circuit outside capacitance C1, buffer resistance R1 and resistance R 2, the power switch pipe Q3 on driving transformer B1 and former limit thereof; The circuit that the accelerating power switching tube is opened and turn-offed; Described online power-supply circuit is made up of diode D1 and capacitor C 3; The totem structure that the circuit that described accelerating power switching tube is opened and turn-offed is made up of triode Q1 and Q2; Annexation is: the end after the secondary said speed-up capacitor C2 of a termination of said driving transformer B1 and 1 parallel connection of buffering resistance R; The signal input part of the said totem of another termination after this speed-up capacitor C2 and 1 parallel connection of buffering resistance R; And on buffer resistance R1 and electric capacity, response speed that can signal for faster; One end of the anode of described diode D1 and capacitor C 3 all connects the feeder ear of totem, and the source electrode of the said power switch pipe Q3 of another termination of this capacitor C 3, the negative electrode of this diode D1 connects the signal input part of said totem; The signal input part of the said totem of one termination of said resistance R 2, the source electrode of the said power switch pipe Q3 of another termination of this resistance R 2; The secondary other end of the cold end of said totem and said driving transformer B1 all connects the source electrode of said power switch pipe Q3.

It also comprises clamp circuit, and this clamp circuit is diode D2, and its anode connects the signal input part of totem, and negative electrode connects the source electrode of said power switch pipe.This diode D2 serves as the effect that prevents power switch pipe Q3 reverse breakdown, and the reverse voltage that makes power switch pipe Q3 bear is clamped down on about 0.7V.Thereby guaranteed the high efficiency of this drive circuit, fail safe.

It also comprises resistance R 3, the drive end of the said totem of a termination of this resistance R 3, the driving stage of another termination power switch pipe.This resistance R 3 makes that power switch pipe can be open-minded accurately.

The parameter of each element is following among the embodiment: capacitor C 1 model: 1U/50V; Speed-up capacitor C2 and capacitor C 3 models: 0.1U/50V; Buffer resistance R1 and resistance R 3 models: 10R, R2 model: 3K Ω, the model of diode D1 and D2: 1N4148; Triode Q1 model: 9013 NPN type, Q2 model: 9015 positive-negative-positive.

The workflow of the utility model: send PWM by control circuit and drive needed signal and energy; Reach the secondary of transformer to energy and signal through capacitance and driving transformer; Then pass through buffer resistance and speed-up capacitor; Online power-supply circuit and Q1 through D1 and C3 composition forms the circuit that the accelerating power switching tube is opened again, remedied because the big inadequately problem of the undesirable transient current that causes of transformer self parameter makes that through R3 power switch pipe can be open-minded fast and accurately; When the drive signal end, the quick discharging circuit of forming through Q2 makes power switch pipe turn-off fast and accurately.

Claims (5)

Translated fromChinese

1.一种改善隔离驱动电路性能的电路，包括驱动变压器B1及其原边的隔直电容C1、缓冲电阻R1和电阻R2、功率开关管Q3，其特征在于：它还包括加速电容C2、在线取电电路；加速功率开关管开通及关断的电路；所述隔直电容C1接收的信号到达驱动变压器B1的次级后经过加速电容C2和缓冲电阻R1并联后的电路及电阻R2，使信号加速且完整的进入所述的加速功率开关管开通及关断的电路而控制所述功率开关管Q3快速的开通及关断。1. A circuit for improving the performance of an isolated drive circuit, comprising a DC blocking capacitor C1 of a drive transformer B1 and its primary side, a snubber resistor R1 and a resistor R2, a power switch tube Q3, characterized in that: it also includes an acceleration capacitor C2, an online Power-taking circuit; the circuit for turning on and off the accelerating power switch tube; the signal received by the DC blocking capacitor C1 reaches the secondary side of the drive transformer B1 and passes through the circuit after the accelerating capacitor C2 and the buffer resistor R1 are connected in parallel and the resistor R2, so that the signal Accelerate and completely enter the circuit of accelerating the turn-on and turn-off of the power switch tube to control the fast turn-on and turn-off of the power switch tube Q3.2.根据权利要求1 所述的一种改善隔离驱动电路性能的电路，其特征在于：所述的在线取电电路由二极管D1和电容C3组成，该二极管D1的阳极和电容C3的一端均接加速功率开关管开通及关断电路的供电端，而该电容C3的另一端接所述功率开关管的源极，该二极管D1的阴极接所述加速功率开关管开通及关断电路的信号输入端。2. A circuit for improving the performance of an isolated drive circuit according to claim 1, characterized in that: the online power-taking circuit is composed of a diode D1 and a capacitor C3, and the anode of the diode D1 is connected to one end of the capacitor C3 The power supply end of the acceleration power switch tube is turned on and off, and the other end of the capacitor C3 is connected to the source of the power switch tube, and the cathode of the diode D1 is connected to the signal input of the acceleration power switch tube on and off circuit end.3.根据权利要求1 所述的一种改善隔离驱动电路性能的电路，其特征在于：所述的加速功率开关管开通及关断的电路是由三极管Q1及Q2组成的图腾柱结构。3. A circuit for improving the performance of an isolated drive circuit according to claim 1, characterized in that: the circuit for accelerating the turn-on and turn-off of the power switch tube is a totem pole structure composed of triodes Q1 and Q2.4.根据权利要求1至3 所述的任一种改善隔离驱动电路性能的电路，其特征在于：它还包括钳位电路，该钳位电路是二极管D2，该二极管D2的阳极接图腾柱的信号输入端，阴极接所述功率开关管Q3的源极。4. The circuit for improving the performance of an isolated drive circuit according to any one of claims 1 to 3, characterized in that: it also includes a clamping circuit, the clamping circuit is a diode D2, and the anode of the diode D2 is connected to the totem pole Signal input terminal, the cathode is connected to the source of the power switch tube Q3.5.根据权利要求1至3 所述的任一种改善隔离驱动电路性能的电路，其特征在于：它还包括电阻R3，该电阻R3的一端接所述图腾柱的驱动端，另一端接功率开关管的驱动极。5. The circuit for improving the performance of an isolated drive circuit according to any one of claims 1 to 3, characterized in that it also includes a resistor R3, one end of the resistor R3 is connected to the driving end of the totem pole, and the other end is connected to the power The drive pole of the switch tube.

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