阅读说明：本技术 一种增量式编码器ic中绝对位置输出的方法 (Method for outputting absolute position in incremental encoder IC ) 是由 胡枭 张超 汪坚雄 于 2020-07-09 设计创作，主要内容包括：本发明公开了一种增量式编码器IC中绝对位置输出的方法。可以实现在编码器上电工作时或控制端发送绝对位置请求时,复用增量式编码器的输出接口,从同一输出端口输出代表绝对值位置的脉冲信号,从而使计数设备获得输出位移变化量的绝对位置信息。该方法兼容增量式编码器的电机系统的输出方式,不需要额外的接口,节省成本；该方法不需要的额外位置变化,可以实时获取当前位置。本发明结构简单,占用面积小,不需要额外的接口,不需要的额外位置变化,不会增加电机系统成本,可应用于电机控制,电机传感等领域。(The invention discloses a method for outputting absolute position in an incremental encoder IC. The output interface of the incremental encoder can be multiplexed when the encoder is electrified and works or the control end sends an absolute position request, and the pulse signal representing the absolute value position is output from the same output port, so that the counting equipment can obtain the absolute position information of the output displacement variation. The method is compatible with the output mode of the motor system of the incremental encoder, does not need an additional interface and saves the cost; the method can acquire the current position in real time without needing extra position change. The invention has simple structure, small occupied area, no need of additional interfaces and no need of additional position change, does not increase the cost of a motor system, and can be applied to the fields of motor control, motor sensing and the like.)

1. A method of absolute position output in an incremental encoder IC, comprising the steps of:

step (1): receiving an absolute position request signal and outputting a selection signal;

step (2): outputting a corresponding selection output signal according to the selection signal;

and (3): and generating and outputting an output position signal pulse according to the selection output signal.

2. The method of claim 1, wherein the step (1) comprises:

the input end of the input control module is connected with an absolute position request signal sent by an external counting and control IC and used for outputting a selection signal according to the external absolute position request signal.

3. The method of claim 2, wherein the step (2) comprises:

the mode selection module selects the increment signal output by the increment signal generation circuit or the absolute value signal output by the absolute value position generation circuit according to the selection signal input from the input control module, and outputs the signal.

4. A method of absolute position output in an incremental encoder IC as claimed in claim 3, wherein said step (3) comprises:

and the output driving module generates and outputs an output position signal pulse according to the signal input from the mode selection module.

5. A method of absolute position output in an incremental encoder IC as claimed in any one of claims 1 to 4, in which, after power-up of the encoder, the output port outputs a pulse signal representing the absolute position, and then outputs a signal representing the incremental position.

6. The method of claim 5, wherein when the encoder IC is operating normally and outputting the incremental position signal, the external control terminal sends an absolute position request signal, and outputs a pulse signal representing the absolute position at the same output port.

7. The method of claim 5, wherein the absolute value position code output format is 1 IO port output code, 2 IO port output code or 3 IO port output code.

8. The method of claim 7, wherein 1 IO port is used to output code: selecting any output interface in the encoder output A, B, Z for output, wherein the number of output pulses is related to the absolute position value; 2 IO ports are adopted to output codes: selecting any two output interfaces in the encoder output A, B, Z for output, outputting two pulses which are orthogonal in 90 degrees, and outputting pulse combinations which are orthogonal in 90 degrees, wherein the number of the pulse combinations is related to the absolute position value; 3 IO ports are adopted to output codes: and outputting 120-degree orthogonal pulse combinations by adopting 3 IO ports to output absolute value position codes, wherein the number of the pulse combinations is related to the absolute position value.

Technical Field

The invention relates to the technical field of electronic circuits, in particular to a method for outputting absolute positions in an incremental encoder IC.

Background

The incremental encoder IC is an application specific integrated circuit that converts the amount of displacement change into a periodic electrical signal, converts the electrical signal into counting pulses, and expresses the magnitude of the displacement by the number of pulses. Incremental encoders typically have a three-way signal output (differential has six signals): A. b, Z, wherein the signals of the A, B two channels are generally orthogonal (90 ° out of phase) pulsed signals and the Z phase is a zero pulse signal. Its advantages are simple structure, long average life of machine (more than tens of thousands of hours), high anti-interference power and reliability, and long-distance transmission.

The incremental encoder has the defects that absolute position information of displacement variation cannot be output, when the encoder is not moved or is powered off, the position can be memorized only by internal memory of counting equipment, and the encoder cannot move at any time; when the incoming call works, the encoder can not be interfered to lose the pulse in the process of outputting the pulse, otherwise, the position memorized by the counting device can be shifted.

One way to solve this problem is to add a reference point, which the encoder corrects into the memory location of the counting device each time it passes. Therefore, in industrial control, a reference point is found first in each operation, and the method of starting machine and changing is adopted. For example, the positioning of a printer scanner is based on the principle of an incremental encoder, and the printer scanner needs to move back and forth to find a reference zero point every time the printer scanner is started, and then the printer scanner can normally work. Therefore, the method is only suitable for the application occasions of allowing the position to move when the mobile terminal is started, and the current position cannot be obtained in real time; on the other hand, such a few reference points set in advance, before the reference point, cannot guarantee the accuracy of the position.

Another way to solve this problem is to use an absolute value encoder, each position of which corresponds to a certain digital code, and the current position can be obtained in real time, and the output of which is typically a protocol output. Because the absolute value encoder has higher cost, the method is suitable for a high-value motor system; on the other hand, the output interface of the absolute value encoder is incompatible with the output interface of the incremental encoder, and the problem of the incremental encoder cannot be solved.

Disclosure of Invention

In view of the shortcomings in the prior art, an object of the embodiments of the present invention is to provide a method for outputting an absolute position in an incremental encoder IC, so as to solve the above-mentioned problems in the background art.

In order to achieve the purpose, the invention provides the following technical scheme:

a method of absolute position output in an incremental encoder IC, comprising the steps of:

step (1): receiving an absolute position request signal and outputting a selection signal;

step (2): outputting a corresponding selection output signal according to the selection signal;

and (3): and generating and outputting an output position signal pulse according to the selection output signal.

As a further aspect of the present invention, the step (1) specifically includes:

the input end of the input control module is connected with an absolute position request signal sent by an external counting and control IC and used for outputting a selection signal according to the external absolute position request signal.

As a further aspect of the present invention, the step (2) specifically includes:

the mode selection module selects the increment signal output by the increment signal generation circuit or the absolute value signal output by the absolute value position generation circuit according to the selection signal input from the input control module, and outputs the signal.

As a further aspect of the present invention, the step (3) specifically includes:

and the output driving module generates and outputs an output position signal pulse according to the signal input from the mode selection module.

As a further scheme of the invention, after the encoder is electrified and operated, a pulse signal representing the absolute value position is output at the output port, and then a signal representing the incremental position is output.

As a further scheme of the invention, when the encoder IC works normally and outputs the incremental position signal and the external control end sends the absolute position request signal, the pulse signal representing the absolute value position is output at the same output port.

As a further scheme of the invention, the absolute value position code output format adopts 1 IO port output code, 2 IO port output codes or 3 IO port output codes.

As a further scheme of the present invention, 1 IO port is used to output codes: selecting any output interface in the encoder output A, B, Z for output, wherein the number of output pulses is related to the absolute position value; 2 IO ports are adopted to output codes: selecting any two output interfaces in the encoder output A, B, Z for output, outputting two pulses which are orthogonal in 90 degrees, and outputting pulse combinations which are orthogonal in 90 degrees, wherein the number of the pulse combinations is related to the absolute position value; 3 IO ports are adopted to output codes: and outputting 120-degree orthogonal pulse combinations by adopting 3 IO ports to output absolute value position codes, wherein the number of the pulse combinations is related to the absolute position value.

The invention has the beneficial effects that:

1. the invention provides a method for outputting an absolute position in an incremental encoder IC, which solves the problems that the incremental encoder IC in the prior art cannot output absolute position information of displacement variation, an absolute value encoder output interface is incompatible with the incremental encoder output interface, and the absolute value encoder is high in cost. When the encoder is powered on to work or the control end sends an absolute position request, the output interface of the incremental encoder is multiplexed, and a pulse signal representing the absolute value position is output from the same output port, so that the counting equipment can obtain the absolute position information of the output displacement variation. The method is compatible with the output mode of the motor system of the incremental encoder, does not need an additional interface and saves the cost; the method can acquire the current position in real time without needing extra position change. The invention has simple structure, small occupied area, no need of additional interfaces and no need of additional position change, does not increase the cost of a motor system, and can be applied to the fields of motor control, motor sensing and the like.

2. Because the output mode of the motor system compatible with the incremental encoder is adopted, an additional interface is not needed, output cables are saved, and the existing incremental encoder has good compatibility; because the pulse signal representing the absolute value position can be output, the counting device can obtain the absolute position information of the output displacement variation, the current position can be obtained in real time due to the unnecessary extra position variation; due to the fact that the output interface of the incremental encoder is multiplexed, the cost of a motor system cannot be increased, and the incremental encoder has the advantage of cost.

To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Description of the drawings:

FIG. 1 is a system architecture diagram provided by the present invention;

FIG. 2 is a timing diagram of the signal characteristics of the present invention, after the encoder is powered on, the pulse signal representing the absolute position is output first, and then the incremental position is output;

fig. 3 is a timing diagram of the characteristics of the pulse signal output representing the absolute position when the control terminal sends an absolute position request according to the present invention.

Fig. 4 is a timing chart of the encoding characteristics output by using 1 IO port according to the present invention.

Fig. 5 is a timing chart of the encoding characteristics provided by the present invention using 2 IO ports for output.

FIG. 6 is a timing diagram of the output encoding feature provided by the present invention using 3 IO ports.

The specific implementation mode is as follows:

the invention will be described more fully and clearly in connection with the accompanying drawings and the accompanying knowledge, and it is to be understood that the circuit diagrams described are merely exemplary embodiments of the invention, and are not intended to represent all exemplary embodiments.

Referring to fig. 1 to 6, a method for outputting an absolute position in an incremental encoder IC may simplify a circuit structure, reduce additional interfaces, maintain better compatibility, and reduce additional position changes.

The invention is used for absolute position output in an incremental encoder IC, and comprises the following steps: the device comprises an input control module, a mode selection module, an incremental signal generation circuit, an absolute value position generation circuit and an output driving module;

the input control module has an input end connected with a control signal sent by an external counting and control IC, outputs a selection signal according to the external signal, inputs the selection signal to one input end of the mode selection module and is used for controlling the selection and the output of the incremental signal and the absolute value signal; the mode selection module is used for generating a 2-out-of-one output signal according to a selection signal input into the control module, an increment signal output by the increment signal generation circuit and an absolute value signal output by the absolute value position generation circuit, and inputting the output signal to one input end of the output driving module; an increment signal generation circuit for generating an increment signal; an absolute value position generating circuit for generating an absolute value position signal; and the output driving module generates and outputs position signal pulses according to the 2-out-of-one output signal input from the mode selection module.

In the invention, after the encoder is electrified and operated, a pulse signal representing the absolute value position is output firstly, and then a signal of the increment position is output. When the encoder works normally and outputs the incremental position signal, if the external control end sends an absolute position request signal, a pulse signal representing the absolute value position is output from the same output interface.

The absolute value coding output format has three output coding modes, and 1 IO port output code, 2 IO port output codes or 3 IO port output codes can be adopted. The method specifically comprises the following steps: 1 IO port is adopted to output codes: and selecting A, B, Z any IO interface to output, wherein the number of output pulses is related to the absolute position value. 2 IO ports are adopted to output codes: any two IO interfaces in A, B, Z are selected to output 90-degree orthogonal pulse combinations, and the number of the output pulse combinations is related to the absolute position value. 3 IO ports are adopted to output codes: and selecting all 3 output IOs, outputting 120-degree orthogonal pulse combinations, wherein the number of the output pulse combinations is related to the absolute position value.

Because the output mode of the motor system compatible with the incremental encoder is adopted, an additional interface is not needed, output cables are saved, and the existing incremental encoder has good compatibility; the pulse signal representing the absolute value position can be output, so that the counting equipment can obtain absolute position information of output displacement variation, and the current position can be obtained in real time due to unnecessary extra position variation; due to the fact that the output interface of the incremental encoder is multiplexed, the cost of a motor system cannot be increased, and the incremental encoder has the advantage of cost.