阅读说明：本技术 一种可调电阻组合电路的控制方法 (Control method of adjustable resistor combined circuit ) 是由 朱浩明 裴芳利 王培征 雷丰科 黄云龙 于 2021-01-04 设计创作，主要内容包括：本发明供一种可调电阻组合电路的控制方法,组合电路包括粗调电路和微调电路；粗调电路与微调电路串联；本发明通过控制器根据目标电阻值Rd,对不同的电位器分别进行调节,通过步进值进计算出粗调电路的电位器的电阻值；进而通过求余运算计算出余数m；控制器根据余数m的数值对不同微调电位器的电阻Rw进行调节；这样精度高、控制灵活。(The invention provides a control method of an adjustable resistance combined circuit, wherein the combined circuit comprises a coarse tuning circuit and a fine tuning circuit; the coarse tuning circuit is connected in series with the fine tuning circuit; according to the invention, different potentiometers are respectively regulated by the controller according to the target resistance value Rd, and the resistance value of the potentiometer of the coarse regulating circuit is calculated through the step value; further calculating a remainder m through remainder operation; the controller adjusts the resistance Rw of different trimmer potentiometers according to the value of the remainder m; therefore, the precision is high and the control is flexible.)

1. A control method of an adjustable resistance combined circuit comprises a coarse tuning circuit and a fine tuning circuit; the coarse tuning circuit is connected in series with the fine tuning circuit; the method is characterized in that: the combined circuit comprises a first resistance end, a second resistance end and a controller; the first resistance end is connected with the input end of the coarse tuning circuit; the output end of the coarse tuning circuit is connected with the input end of the fine tuning circuit; the output end of the fine tuning circuit is connected with the second resistor end; the controller is connected with the control end of the coarse tuning circuit and the control end of the fine tuning circuit; the coarse adjustment circuit comprises a first coarse adjustment potentiometer, a second coarse adjustment potentiometer and a third coarse adjustment potentiometer; the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer are connected in parallel; the fine tuning circuit comprises more than one fine tuning potentiometer;

the control method of the combination circuit comprises the following steps:

(1) presetting a target resistance value Rd; presetting the number n of the fine-tuning potentiometers; the step value of the third coarse potentiometer is RJ 1; the step value of the second coarse potentiometer is RK 1; the step value of the first coarse potentiometer is RL 1;

(2) performing an RJ = RJ1 × F (Rd/RJ 1) operation; obtaining the value of RJ; RJ is the current resistance adjustment value of the third coarse adjustment potentiometer when the target resistance is Rd;

(3) performing a RK = RK 1F (Rd-RJ) operation; obtaining a value of RK; RK is the current resistance adjusting value of the second coarse adjustment potentiometer when the target resistance is Rd;

(4) performing an RL = RL 1F (Rd-RJ-RK) operation; obtaining the value of RL; RL is the current resistance adjustment value of the first coarse potentiometer when the target resistance is Rd;

(5) performing an Rb = Rd-RJ-RK-RL operation; obtaining the value of Rb; rb is the current resistance adjusting value after the n trimming potentiometers are connected in series when the target resistance is Rd;

(6) performing m = (Rb × n)% n operation; obtaining the value of m; m is the remainder of the fine tuning circuit;

(7) performing an R0= Rb n-m operation; obtaining a value of R0; r0 is the reference resistance of the trimming circuit;

(8) if m =0, performing step (9); if m is larger than 0, performing the step (10);

(9) setting the resistance values of the n trimming potentiometers as R0;

(10) setting the resistance values of the (n-m) trimming potentiometers to R0; the resistance values of the m trimmers are set to R0+ n.

2. The method of claim 1, wherein the method further comprises: the controller is independently connected with the n fine-tuning potentiometers; n has a value of 10.

3. The method of claim 1, wherein the method further comprises: the third coarse potentiometer step value RJ1 is greater than the second coarse potentiometer step value RK 1.

4. The method of claim 3, wherein the method further comprises: the step value RK1 for the second coarse potentiometer is greater than the step value RL1 for the first coarse potentiometer.

5. The method of claim 1, wherein the method further comprises: the sliding end of the first coarse adjustment potentiometer is connected with the first resistor end, one end of the first coarse adjustment potentiometer is connected with the controller, the other end of the first coarse adjustment potentiometer is connected with the sliding end of the second coarse adjustment potentiometer, one end of the second coarse adjustment potentiometer is connected with the controller, and the other end of the second coarse adjustment potentiometer is connected with the sliding end of the third coarse adjustment potentiometer; one end of a third coarse adjustment potentiometer is connected with the controller, the other end of the third coarse adjustment potentiometer is connected with the sliding end of more than one fine adjustment potentiometer, one end of more than one fine adjustment potentiometer is connected with the controller, and the other end of more than one fine adjustment potentiometer is connected with the second resistor end after being connected.

Technical Field

The invention relates to the technical field of electronic circuits, in particular to a control method of an adjustable resistor combination circuit.

Background

A digital potentiometer (also called a digitally controlled programmable resistor) is a new type of integrated circuit for digital and analog mixed signal processing of Complementary Metal Oxide Semiconductor (CMOS) instead of a traditional mechanical potentiometer (i.e., an analog potentiometer). The digital potentiometer is controlled by a digital input and generates an analog output. The tap current maximum can range from a few hundred microamperes to a few milliamperes depending on the digital potentiometer. At present, a digital potentiometer is generally used for simulating the resistance value of a temperature-variable resistor, and a resistance value signal of the temperature-variable resistor is converted into an analog signal, and the adjustable minimum resistance value of a resistor network in the digital potentiometer is too large, that is, the adjustment precision of the digital potentiometer is too large, so that the resistance value of the temperature-variable resistor cannot be accurately simulated.

To solve the above problems, the chinese application No. 201911324115.5; a patent document published as 2020.4.17 discloses a variable resistance analog circuit and a parameter design method of the variable resistance analog circuit; the variable resistance analog circuit comprises a fine tuning circuit, a coarse tuning circuit and a controller which is respectively connected with a first control end of the fine tuning circuit and a second control end of the coarse tuning circuit; the controller is used for adjusting the resistance value of the fine adjustment circuit and/or the coarse adjustment circuit; the input end of the coarse tuning circuit is connected with the input end of the variable resistance analog circuit, and the output end of the coarse tuning circuit is connected with the input end of the fine tuning circuit; the input end of the fine adjusting circuit is connected with the output end of the coarse adjusting circuit, the output end of the fine adjusting circuit is connected with the output end of the variable resistance analog circuit, and the input end of the fine adjusting circuit is connected with the input end of the variable resistance analog circuit.

But the first resistance precision resistor of the variable resistance analog circuit; and the adjustment precision of the fine adjustment circuit is changed by connecting the first resistor in parallel with the digital potentiometer; the error of the circuit is large, and the resistance value of the circuit is not linearly adjustable.

Disclosure of Invention

The invention provides a control method of an adjustable resistor combination circuit, which has a simple circuit structure and high resistance value adjustment precision.

In order to achieve the purpose, the technical scheme of the invention is as follows: a control method of an adjustable resistance combined circuit comprises a first resistance end, a second resistance end and a controller; the first resistance end is connected with the input end of the coarse tuning circuit; the output end of the coarse tuning circuit is connected with the input end of the fine tuning circuit; the output end of the fine tuning circuit is connected with the second resistor end; the controller is connected with the control end of the coarse tuning circuit and the control end of the fine tuning circuit; the coarse adjustment circuit comprises a first coarse adjustment potentiometer, a second coarse adjustment potentiometer and a third coarse adjustment potentiometer; the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer are connected in parallel; the fine tuning circuit comprises more than one fine tuning potentiometer;

the control method of the combination circuit comprises the following steps:

(1) presetting a target resistance value Rd; presetting the number n of the fine-tuning potentiometers; the step value of the third coarse potentiometer is RJ 1; the step value of the second coarse potentiometer is RK 1; the step value of the first coarse potentiometer is RL 1;

(2) performing an RJ = RJ1 × F (Rd/RJ 1) operation; obtaining the value of RJ; RJ is the current resistance adjustment value of the third coarse adjustment potentiometer when the target resistance is Rd;

(3) performing a RK = RK 1F (Rd-RJ) operation; obtaining a value of RK; RK is the current resistance adjusting value of the second coarse adjustment potentiometer when the target resistance is Rd;

(4) performing an RL = RL 1F (Rd-RJ-RK) operation; obtaining the value of RL; RL is the current resistance adjustment value of the first coarse potentiometer when the target resistance is Rd;

(5) performing an Rb = Rd-RJ-RK-RL operation; obtaining the value of Rb; rb is the current resistance adjusting value after the n trimming potentiometers are connected in series when the target resistance is Rd;

(6) performing m = (Rb × n)% n operation; obtaining the value of m; m is the remainder of the fine tuning circuit;

(7) performing an R0= Rb n-m operation; obtaining a value of R0; r0 is the reference resistance of the trimming circuit;

(8) if m =0, performing step (9); if m is larger than 0, performing the step (10);

(9) setting the resistance values of the n trimming potentiometers as R0;

(10) setting the resistance values of the (n-m) trimming potentiometers to R0; the resistance values of the m trimmers are set to R0+ n.

In the method, the controller firstly adjusts the third coarse potentiometer by a step value according to a target resistance value Rd, then determines the current adjustment values of the second coarse potentiometer and the first coarse potentiometer, because the coarse resistor is connected with the fine potentiometer in series, and a plurality of fine potentiometers in the fine potentiometer are connected in parallel, the resistance values of the fine potentiometers are determined according to the subtraction of the resistance values of the three coarse potentiometers from the target resistance value, then the upper adjustment values of n fine potentiometers are determined, the adjustment resistance values of the fine potentiometers under different conditions are determined according to the adjustment and division of the resistance values of the fine potentiometers and n, under the condition that the fine potentiometers cannot be adjusted, the fine potentiometers are adjusted, the fine potentiometers and the fine potentiometers are respectively adjusted, so that under the condition that the step value is not changed, the adjustment of the fine potentiometer and the coarse potentiometers is more reliable, and the target resistance value after adjustment is more reliable, different potentiometers are respectively adjusted, because the fine adjustment circuit and the coarse adjustment circuit are arranged in series; the adjusting resistance value of the fine-tuning potentiometer is obtained by calculating the adjusting resistance values of the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer; meanwhile, the resistance values of the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer are calculated through the step values, so that the controller can control the resistance values by changing the adjusting steps of the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer, and the resistance values are linearly adjustable; simultaneously performing RoundDown (downward (direction of decreasing absolute value) rounding number) operation when calculating the resistance values of the first coarse potentiometer, the second coarse potentiometer and the third coarse potentiometer; thus, the precision is high; the scheme also obtains a remainder m within the range of [0, n ] through remainder operation; the controller adjusts the resistance values of different trimmer potentiometers according to the numerical value of the remainder m; thus, the precision is high and the control is flexible; meanwhile, the combined circuit is formed by connecting the fine tuning circuit and the coarse tuning circuit in series, and the fine tuning circuit and the coarse tuning circuit are composed of different potentiometers, so that the circuit design is simple and the cost is low.

Furthermore, the controller is independently connected with the n trimming potentiometers; n has a value of 10.

Further, the third coarse potentiometer step value RJ1 is greater than the second coarse potentiometer step value RK 1.

Further, the step RK1 for the second coarse potentiometer is greater than the step RL1 for the first coarse potentiometer.

Furthermore, the sliding end of the first coarse adjustment potentiometer is connected with the first resistor end, one end of the first coarse adjustment potentiometer is connected with the controller, the other end of the first coarse adjustment potentiometer is connected with the sliding end of the second coarse adjustment potentiometer, one end of the second coarse adjustment potentiometer is connected with the controller, and the other end of the second coarse adjustment potentiometer is connected with the sliding end of the third coarse adjustment potentiometer; one end of a third coarse adjustment potentiometer is connected with the controller, the other end of the third coarse adjustment potentiometer is connected with the sliding end of more than one fine adjustment potentiometer, one end of more than one fine adjustment potentiometer is connected with the controller, and the other end of more than one fine adjustment potentiometer is connected with the second resistor end after being connected.

Drawings

FIG. 1 is a schematic diagram of a combinational circuit using the present invention.

FIG. 2 is a flow chart of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1-2; a control method of an adjustable resistance combined circuit comprises a first resistance end 1, a second resistance end 2 and a controller 3; the first resistance end 1 is connected with the input end of the coarse tuning circuit; the output end of the coarse tuning circuit is connected with the input end of the fine tuning circuit; the output end of the fine tuning circuit is connected with the second resistor end 2; the controller 3 is connected with the control end of the coarse tuning circuit and the control end of the fine tuning circuit; the coarse adjustment circuit includes a first coarse potentiometer 41, a second coarse potentiometer 42, and a third coarse potentiometer 43; the first coarse potentiometer 41, the second coarse potentiometer 42 and the third coarse potentiometer 43 are connected in parallel; the trim circuit includes more than one trim potentiometer 44. More than one trimmer potentiometer 44 is connected to the controller 3 individually. In the present embodiment, ten trimmers 44 are provided. The step value RJ1 of the third coarse potentiometer 43 is greater than the step value RK1 of the second coarse potentiometer 42, and the step value RK1 of the second coarse potentiometer 42 is greater than the step value RL1 of the first coarse potentiometer 41.

The sliding end of the first coarse adjustment potentiometer is connected with the first resistor end, one end of the first coarse adjustment potentiometer is connected with the controller, the other end of the first coarse adjustment potentiometer is connected with the sliding end of the second coarse adjustment potentiometer, one end of the second coarse adjustment potentiometer is connected with the controller, and the other end of the second coarse adjustment potentiometer is connected with the sliding end of the third coarse adjustment potentiometer; one end of a third coarse adjustment potentiometer is connected with the controller, the other end of the third coarse adjustment potentiometer is connected with the sliding end of more than one fine adjustment potentiometer, one end of more than one fine adjustment potentiometer is connected with the controller, and the other end of more than one fine adjustment potentiometer is connected with the second resistor end after being connected.

In this embodiment, the first coarse potentiometer 41, the second coarse potentiometer 42, the third coarse potentiometer 43, and the fine potentiometer 44 are all digital potentiometers; the third coarse potentiometer 43 is of the type: X9C 104; the second coarse potentiometer 42 is of the type: X9C 103; the first coarse potentiometer 41 and the fine potentiometer 44 are of type X9C 102.

The control method of the combination circuit comprises the following steps:

(1) presetting a target resistance value Rd; presetting the number n of the fine-tuning potentiometers; the step value of the third coarse potentiometer is RJ 1; the step value of the second coarse potentiometer is RK 1; the first coarse potentiometer is stepped by RL 1.

(2) Performing an RJ = RJ1 × F (Rd/RJ 1) operation; obtaining the value of RJ; RJ is the current resistance adjustment value of the third coarse potentiometer when the target resistance is Rd.

(3) Performing a RK = RK 1F (Rd-RJ) operation; obtaining a value of RK; RK is the current resistance adjustment value of the second coarse potentiometer when the target resistance is Rd.

(4) Performing an RL = RL 1F (Rd-RJ-RK) operation; obtaining the value of RL; RL is the current resistance adjustment value of the first coarse potentiometer when the target resistance is Rd.

(5) Performing an Rb = Rd-RJ-RK-RL operation; obtaining the value of Rb; rb is the current resistance adjustment value after the n trimming potentiometers are connected in series when the target resistance is Rd.

(6) Performing m = (Rb × n)% n operation; obtaining the value of m; m is the remainder of the trimming circuit.

(7) Performing an R0= Rb n-m operation; obtaining a value of R0; r0 is the reference resistance of the trimming circuit.

(8) If m =0, performing step (9); if m > 0, proceed to step (10).

(9) The resistance values of the n trimmers are set to R0.

(10) Setting the resistance values of the (n-m) trimming potentiometers to R0; the resistance values of the m trimmers are set to R0+ n.

In the steps (2), (3) and (4), F is a RoundDown (direction of decreasing absolute value) rounding numerical operation.

In the method, the controller firstly adjusts the third coarse potentiometer by a step value according to a target resistance value Rd, then determines the current adjustment values of the second coarse potentiometer and the first coarse potentiometer, because the coarse resistor is connected with the fine potentiometer in series, and a plurality of fine potentiometers in the fine potentiometer are connected in parallel, the resistance values of the fine potentiometers are determined according to the subtraction of the resistance values of the three coarse potentiometers from the target resistance value, then the upper adjustment values of n fine potentiometers are determined, the adjustment resistance values of the fine potentiometers under different conditions are determined according to the adjustment and division of the resistance values of the fine potentiometers and n, under the condition that the fine potentiometers cannot be adjusted, the fine potentiometers are adjusted, the fine potentiometers and the fine potentiometers are respectively adjusted, so that under the condition that the step value is not changed, the adjustment of the fine potentiometer and the coarse potentiometers is more reliable, and the target resistance value after adjustment is more reliable, different potentiometers are respectively adjusted, because the fine adjustment circuit and the coarse adjustment circuit are arranged in series; the adjusting resistance value of the fine-tuning potentiometer is obtained by calculating the adjusting resistance values of the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer; meanwhile, the resistance values of the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer are calculated through the step values, so that the controller can control the resistance values by changing the adjusting steps of the first coarse-tuning potentiometer, the second coarse-tuning potentiometer and the third coarse-tuning potentiometer, and the resistance values are linearly adjustable; simultaneously performing RoundDown (downward (direction of decreasing absolute value) rounding number) operation when calculating the resistance values of the first coarse potentiometer, the second coarse potentiometer and the third coarse potentiometer; thus, the precision is high; the scheme also obtains a remainder m within the range of [0, n ] through remainder operation; the controller adjusts the resistance values of different trimmer potentiometers according to the numerical value of the remainder m; thus, the precision is high and the control is flexible; meanwhile, the combined circuit is formed by connecting the fine tuning circuit and the coarse tuning circuit in series, the fine tuning circuit and the coarse tuning circuit are composed of different potentiometers, the circuit design is simple, the cost is low, and in the scheme, the step (1) is specifically as follows: the value of n is preset to be 10.

In the step (6), if Rb is 53; then m is 3; if Rb is 40, m is 0. By carrying out the remainder operation, the problem that n cannot be evenly divided by Rb and the resistance value of each fine-tuning potentiometer cannot be accurately controlled according to Rb is avoided.

In the step (9), if m is 2; in step (10), the resistance values of the eight trimmers 44 are set to R0; the resistance values of the two trimmers 44 are set to R0+ n.