CN207926561U - A kind of single channel signal isolation circuit - Google Patents

Abstract

The utility model discloses a kind of single channel signal isolation circuits, including low-pressure side control module, signal isolation module and the high-pressure side control module being sequentially connected；Wherein, low-pressure side control module is output to signal isolation module for generating drive signal, and by drive signal；Signal isolation module includes transformer, and the primary coil of transformer forms the first AC signal, and the first AC signal is transmitted to the secondary coil of transformer so that secondary coil generates the second AC signal according to the drive signal received；High-pressure side control module is handled for receiving the second AC signal.By using above-mentioned technical proposal, the transmission of signal between low pressure side and high pressure side is realized, relative to multi channel signals isolation circuit, effectively reduces circuit cost.

Description

A kind of single channel signal isolation circuit

Technical field

The utility model is related to Signal Isolation Technology field more particularly to a kind of single channel signal isolation circuits.

Background technology

With the development of science and technology with the diversity of product demand, the function of electrical equipment becomes more diverse.And in electricity During the design and use of device equipment, various signals are will produce：The small signal of existing faint millivolt level, and have number Ten volts of big signal, or even also have the strong signal of up to thousands of volts.Above-mentioned low-voltage signal and high-voltage signal, which will pass through, mutually to be passed on from one to another The process passed and conveyed.In the transmission process of unlike signal, in order to avoid being interfered with each other between low-voltage signal and high-voltage signal, The use of signal isolation circuit is particularly important.

In existing signal isolation circuit, it is broadly divided into following three types：

(1) photoisolator, also referred to as photoelectrical coupler, abbreviation optocoupler.It is the device for carrying out transmission telecommunications number using light as medium Part is usually encapsulated in photophore (infrared light-emitting diode LED) and light-receiving device (photosensitive semiconductor pipe) in same shell.When When input terminal power up signal, photophore emits beam, and light-receiving device receives to flow out from output end with regard to generating photoelectric current after light, from And realize the conversion of " electricity-light-electricity ".Compared with other isolation technologies, photoisolator cost is higher, and there is transmission The problems such as rate is low, power consumption height and LED agings.

(2) inductance type isolator turns since it eliminates the photoelectricity of influence efficiency in photoelectrical coupler in application process Ring change section, therefore its power consumption is only the 1/10~1/50 of photoelectrical coupler.But lead to since the isolation scheme is integrated with multi-path digital Letter, therefore cost is higher, and there is easily the problems such as by external magnetic field or noise jamming.

(3) condenser type isolator is general in the prior art using number isolation in order to improve anti-electromagnetic interference capability Device.But since the isolation scheme is also integrated with multi-path digital communication, and the external independent isolation DC/DC power supply of offer is needed, caused Circuit design is complex, and to lead to the problem of cost higher.

In conclusion when solving the relevant issues of high-low pressure signal isolation, usually all there is circuit complexity in the prior art And cost it is higher the problems such as.

Utility model content

The utility model provides a kind of single channel signal isolation circuit, realizes between low-side signal and high-side signal Transmission, reduce cost, technical solution is as follows：

A kind of single channel signal isolation circuit, the circuit include：The low-pressure side control module that is sequentially connected, signal isolation mould Block and high-pressure side control module；Wherein,

The low-pressure side control module, for generating drive signal, and by the drive signal be output to the signal every From module；

The signal isolation module includes transformer, and the primary coil of the transformer is believed according to the driving received Number, the first AC signal is formed, and the first AC signal is transmitted to the secondary coil of the transformer so that the secondary wire Circle generates the second AC signal；

The high-pressure side control module is handled for receiving second AC signal.

Further, the low-pressure side control module includes：

Power supply unit is connected with the first end of the primary coil of the transformer, for generating supply voltage signal；

First microprocessor is connected with the second end of the primary coil of the transformer, for generating pulse-width signal； Correspondingly,

The primary coil forms first with the pulse-width signal according to the supply voltage received and exchanges letter Number.

Further, the low-pressure side control module further includes：

The first resistor and switch unit being sequentially connected；Wherein,

First resistor and the switch unit are connected between first microprocessor and the second end of the primary coil；

The switch unit for obtaining by first resistor current limliting treated pulse-width signal, and exports switch Signal is to the primary coil；Correspondingly,

The primary coil forms first with the supply voltage signal according to the switching signal received and exchanges letter Number.

Further, the low-pressure side control module further includes：

Filter unit is connected between said supply unit and the first end of the primary coil, for the power supply Voltage signal is filtered, and the voltage signal after being filtered is output to the primary coil.

Further, the signal isolation module further includes：Rectification unit；

The input terminal of the rectification unit is connected with the secondary coil of the transformer, and output end is controlled with the high-pressure side Module is connected, and for carrying out rectifying and wave-filtering processing to second AC signal, obtains target output signal and is output to the height Side control module is pressed, so that the high-pressure side control module is handled.

Further, the filter unit includes second resistance and the first capacitance；Wherein,

The first end of the second resistance is connected with said supply unit, and second end passes through first capacity earth；

Output end and the primary coil of the second end of the second resistance as the voltage signal after being filtered First end is connected.

Further, the rectification unit includes：First diode, 3rd resistor, the second capacitance and the second diode；Its In,

First diode connect with 3rd resistor after circuit, pass through the second capacity earth；

Second diodes in parallel is at the both ends of the second capacitance；

Output end of the cathode of second diode as the target output signal, with the high-pressure side control module It is connected.

Further, the switch unit is NPN type metal-oxide-semiconductor, the base stage of the NPN type triode and the first resistor It is connected；

The emitter of the triode is grounded；

The collector of the triode is connected with the second end of the primary coil of the transformer.

Further, the high-pressure side control module is monomer voltage acquisition chip or the second microprocessor.

The utility model provides a kind of single channel signal isolation circuit, which includes low-pressure side control module, signal Isolation module and high-pressure side control module.Wherein, low-pressure side control module, for generating drive signal, and drive signal is defeated Go out to signal isolation module.Signal isolation module includes transformer, and the primary coil of the transformer is believed according to the driving received Number, form the first AC signal.First AC signal can be transmitted to the secondary wire of transformer by the characteristics of using transformer itself Circle so that secondary coil generates the second AC signal.High-pressure side control module receives the second AC signal and is handled.By adopting With above-mentioned technical proposal, the transmission of signal between low pressure side and high pressure side is realized, and by transformer by low-voltage signal and height Pressure signal is isolated.In addition, single channel isolation circuit design provided by the utility model is simple, there is small, cost Low advantage.Relative to multi channel signals isolation circuit, save signal path, at the same also solve using multi channel signals every The problem of isolated power supply need to be provided separately when from circuit, effectively reduce circuit cost.

Description of the drawings

Fig. 1 is a kind of structural schematic diagram for single channel signal isolation circuit that the utility model embodiment one provides；

Fig. 2 is a kind of structural schematic diagram for single channel signal isolation circuit that the utility model embodiment two provides；

Fig. 3 is a kind of circuit diagram for single channel signal isolation circuit that the utility model embodiment two provides.

Specific implementation mode

The utility model is described in further detail with reference to the accompanying drawings and examples.It is understood that herein Described specific embodiment is used only for explaining the utility model, rather than the restriction to the utility model.It further needs exist for It is bright, it illustrates only for ease of description, in attached drawing and the relevant part of the utility model rather than entire infrastructure.

Embodiment one

Fig. 1 is a kind of structural schematic diagram for single channel signal isolation circuit that the utility model embodiment one provides.The electricity Road may be used in the transmittance process of low-side signal and high-side signal, typical such as electric vehicle BMS (Battery Management System, battery management system) field, it is suitable as single line isolation and wakes up use.As shown in Figure 1, this implementation The single channel signal isolation circuit of offer includes：Low-pressure side control module 110, signal isolation module 120 and the height being sequentially connected Press side control module 130.Wherein,

Low-pressure side control module 110 is output to signal isolation module 120 for generating drive signal, and by drive signal. Signal isolation module 120 includes transformer 121, and the primary coil of the transformer forms first according to the drive signal received AC signal, and the first AC signal is transmitted to the secondary coil of transformer so that secondary coil generates the second AC signal. High-pressure side control module 130 is handled for receiving the second AC signal.

Illustratively, may include MCU (Microcontroller in the low-pressure side control module in the present embodiment Unit, microprocessor), for generating drive signal.The drive signal can be PWM (Pulse Width Modulation, arteries and veins Rush width modulated) signal, or other kinds of square-wave signal.The primary coil of transformer is believed according to the driving received Number formed certain frequency the first AC signal.First AC signal will be transmitted to transformer under the action of electromagnetic field The second AC signal that certain frequency is formed on secondary coil, to realize signal from low pressure side on high-tension side transmission.

Since the technical solution of the present embodiment is to have accessed transformer between low pressure side and high pressure side to carry out signal isolation, Circuit design is simple, under the premise of realizing signal isolation, while also having the advantages such as small, at low cost.

The present embodiment one provides a kind of single channel signal isolation circuit, and mould is controlled by the way that transformer is connected to low-pressure side Between block and high-pressure side control module, using the characteristics of transformer itself, it can be achieved that between low-side signal and high-side signal Transmission, and low-voltage signal and high-voltage signal are isolated.Relative to multi channel signals isolation circuit, it is logical to save signal Road, at the same while also solving the problems, such as using multi channel signals isolation circuit isolated power supply need to be provided separately, effectively reduce electricity Road cost.

Embodiment two

Fig. 2 is a kind of structural schematic diagram for single channel signal isolation circuit that the utility model embodiment two provides, this reality Example two is applied to be optimized on the basis of the above embodiments.As shown in Fig. 2, single channel signal isolation electricity provided in this embodiment Road includes：Low-pressure side control module 210, signal isolation module 220 and high-pressure side control module 230.Wherein, signal isolation module 220 include transformer T1.The internal structure and operation principle of each function module are specifically introduced separately below：

1, low-pressure side control module 210：

Low-pressure side control module 210 includes power supply unit 211, first microprocessor 212, filter unit 213, first resistor With switch unit 214.Specifically,

(1) power supply unit 211 are connected with the first end of the primary coil of transformer T1, for generating supply voltage signal. First microprocessor 212 is connected with the second end of the primary coil of transformer T1, for generating pulse-width signal.At this point, for The pulse-width signal that the supply voltage signal and first microprocessor 212 that electric unit 211 generates generate, which is combined, can be used as drive Dynamic signal is handed over correspondingly, the primary coil of transformer T1 forms first according to the supply voltage and pulse-width signal received Flow signal.

Illustratively, the power supply unit in the present embodiment is power supply VCC.

(2) filter unit 213 are connected between power supply unit 211 and the first end of primary coil, for supply voltage Signal is filtered, and the voltage signal after being filtered is output to primary coil.Filtering in through this embodiment Unit can filter out the interference noise in supply voltage, play smooth voltage.

Specifically, Fig. 3 is a kind of circuit signal for single channel signal isolation circuit that the utility model embodiment two provides Figure.As shown in figure 3, filter unit includes second resistance R2 and the first capacitance C1.Wherein,

The first end of second resistance R2 is connected with power supply unit VCC, and second end is grounded by the first capacitance C1.Second resistance The second end of R2 is connected as the output end of the voltage signal after being filtered with the first end of primary coil.

(3) switch unit 214, with first resistor R1 be connected to first microprocessor 212 and primary coil second end it Between.Switch unit 214, for obtaining by first resistor current limliting treated pulse-width signal, and output switching signal arrives Primary coil.At this point, the pulse-width signal phase that supply voltage signal and switch unit 214 that power supply unit 211 generates generate In conjunction with can be used as drive signal, correspondingly, primary coil forms first according to the switching signal and supply voltage signal received AC signal.

Illustratively, in the present embodiment, switch unit 214 can be NPN type triode Q1 or NMOS.As shown in figure 3, The base stage of triode Q1 is connected with first resistor R1；The emitter of triode Q1 is grounded；The collector of triode Q1 with The second end of the primary coil of transformer is connected.

Specifically, after first microprocessor generates pwm signal, by current-limiting resistance R1 can control triode Q1 conducting and Shutdown, to export the switching signal of certain frequency, this switching signal is also pwm signal.The pwm signal and supply voltage of output It is combined, the first AC signal of certain frequency can be formed on the primary coil of transformer.

2, signal isolation module 220：

In the present embodiment, as shown in Figures 2 and 3, signal isolation module 220 further includes rectification unit 221, the rectification unit 221 input terminal is connected with the secondary coil of transformer, and output end is connected with high-pressure side control module 230, for handing over second It after flowing signal progress rectifying and wave-filtering processing, obtains target output signal and is output to high-pressure side control module 230, so that high-pressure side is controlled Molding block 230 is handled.It is defeated that low ripple, the signal of high stability can be obtained in rectification filtering unit in through this embodiment Go out to high-pressure side control module.

Specifically, as shown in figure 3, rectification unit 221 includes：First diode D1,3rd resistor R3, the second capacitance C2 and Second diode D2.Wherein,

First diode D1 connect with 3rd resistor R3 after circuit, pass through the second capacitance C2 ground connection.Second diode D2 It is connected in parallel on the both ends of the second capacitance C2.Output end of the cathode of second diode D2 as target output signal is controlled with high-pressure side Molding block 230 is connected.

Illustratively, the high-pressure side control module in the present embodiment be monomer voltage acquisition chip or the second microprocessor, For handling the signal that rectification unit exports.The target output voltage of rectification circuit output can be used as high-pressure side control mould The wake-up voltage of block.

The present embodiment on the basis of the above embodiments, by using filter unit, switch unit can transformer just Grade coil forms the first AC signal of certain frequency.First AC signal is transmitted to secondary wire from the primary coil of transformer After circle, rectifying and wave-filtering processing is carried out by rectification unit, low ripple can be obtained, the second AC signal of high stability is output to height Side control module is pressed, so that high-pressure side control module is handled.The single channel signal isolation circuit of the utility model embodiment Transmission of the signal between low-pressure side to high-pressure side not only may be implemented, simultaneously because circuit design is simple, also can reach reduction The effect of circuit cost.

Note that above are only the preferred embodiment and institute's application technology principle of the utility model.Those skilled in the art's meeting Understand, the utility model is not limited to specific embodiment described here, can carry out for a person skilled in the art various bright Aobvious variation is readjusted and is substituted without departing from the scope of protection of the utility model.Therefore, although passing through above example The utility model is described in further detail, but the utility model is not limited only to above example, is not departing from Can also include other more equivalent embodiments in the case that the utility model is conceived, and the scope of the utility model is by appended Right determine.

Claims (9)

1. a kind of single channel signal isolation circuit, which is characterized in that including：The low-pressure side control module that is sequentially connected, signal every From module and high-pressure side control module；Wherein,

The low-pressure side control module is output to the signal isolation mould for generating drive signal, and by the drive signal Block；

The signal isolation module includes transformer, the primary coil of the transformer according to the drive signal received, The first AC signal is formed, and the first AC signal is transmitted to the secondary coil of the transformer so that the secondary coil Generate the second AC signal；

The high-pressure side control module is handled for receiving second AC signal.

2. circuit according to claim 1, which is characterized in that the low-pressure side control module includes：

Power supply unit is connected with the first end of the primary coil of the transformer, for generating supply voltage signal；

First microprocessor is connected with the second end of the primary coil of the transformer, for generating pulse-width signal；Accordingly ,

The primary coil forms the first AC signal according to the supply voltage received and the pulse-width signal.

3. circuit according to claim 2, which is characterized in that the low-pressure side control module further includes：

The first resistor and switch unit being sequentially connected；Wherein,

First resistor and the switch unit are connected between first microprocessor and the second end of the primary coil；

The switch unit, for obtaining by first resistor current limliting treated pulse-width signal, and output switching signal To the primary coil；Correspondingly,

The primary coil forms described first with the supply voltage signal according to the switching signal received and exchanges letter Number.

4. circuit according to claim 2, which is characterized in that the low-pressure side control module further includes：

Filter unit is connected between said supply unit and the first end of the primary coil, for the supply voltage Signal is filtered, and the voltage signal after being filtered is output to the primary coil.

5. circuit according to claim 1, which is characterized in that the signal isolation module further includes：Rectification unit；

The input terminal of the rectification unit is connected with the secondary coil of the transformer, output end and the high-pressure side control module It is connected, after carrying out rectifying and wave-filtering processing to second AC signal, obtains target output signal and be output to the high pressure Side control module, so that the high-pressure side control module is handled.

6. circuit according to claim 4, which is characterized in that the filter unit includes second resistance and the first capacitance； Wherein,

The first end of the second resistance is connected with said supply unit, and second end passes through first capacity earth；

Output end and the first of the primary coil of the second end of the second resistance as the voltage signal after being filtered End is connected.

7. circuit according to claim 5, which is characterized in that the rectification unit includes：First diode, third electricity Resistance, the second capacitance and the second diode；Wherein,

First diode connect with 3rd resistor after circuit, pass through the second capacity earth；

Second diodes in parallel is at the both ends of the second capacitance；

Output end of the cathode of second diode as the target output signal, with the high-pressure side control module phase Even.

8. circuit according to claim 3, which is characterized in that the switch unit is NPN type triode, the triode Base stage be connected with the first resistor；

The emitter of the triode is grounded；

The collector of the triode is connected with the second end of the primary coil of the transformer.

9. circuit according to claim 1, which is characterized in that the high-pressure side control module is monomer voltage acquisition chip Or second microprocessor.