CN103149866A - Method and circuit for increasing resolution of resistance adjustment of DCP (Data Central Processor) - Google Patents

Abstract

The invention discloses a method for increasing the resolution of resistance adjustment of a DCP (Data Central Processor). The method comprises the following steps of: a, selecting n DCPs with the same model number to connect in parallel; and b, selecting an MCU (Micro Control Unit) to control tapping positions of n DCPs. A circuit for improving the resolution of the resistance adjustment of the DCP, which is disclosed by the invention, comprises the MCU and the n DCPs with the same model number, wherein the n DCPs with the same model number are connected in parallel to form an equivalent DCP; the MCU is used for controlling the change of the tapping position of each DCP and ensuring that the tapping position of each DCP is always positioned at the same position; and the n showing the quantity of the DCPs is an integer greater than 1. According to the method and the device disclosed by the invention, a plurality of DCP chips with different model numbers are connected in parallel and a minimum incremental value of the resistance adjustment of the DCP is greatly reduced on the premise of not changing the total tapping quantity of the DCPs, and thus the stepping adjustment resolution of the resistance of the equivalent DCP is increased and the application range of the DCP is widened.

Description

A kind of method and circuit that improves DCP resistance adjustment resolution

Technical field

The present invention relates to the application technology of digital regulation resistance DCP, particularly a kind of method and circuit that improves DCP resistance adjustment resolution.

Background technology

Digital regulation resistance DCP has non-volatile, high reliability, is commonly used in to consist of rheostat or voltage divider in electronic equipment.Microcontroller passes through I ²The serial line interface such as C, SPI is controlled the variation of DCP tap position, realizes the step-by-step adjustment to DCP resistance, and the resolution of its resistance adjustment is determined by total resistance value and the inner tap number of DCP.DCP product in the market only has several tap number such as 16/32/64/100/256/1024, in the situation that some needs the high resolving power step-by-step adjustment, can't meet the demands.

Summary of the invention

In order to overcome the shortcoming of above-mentioned technical matters, the invention provides a kind of method that circuit is simple, control improves DCP resistance adjustment resolution flexibly.

The method of raising DCP resistance adjustment resolution of the present invention, its special feature is, comprises the following steps: a. chooses n same model digital regulation resistance DCP, and this n DCP is connected with parallel form, consists of an equivalent DCP; If the all-in resistance of each DCP is R _T, tap number is that t, tap position are i, the variable resistance of equivalent DCP is R _EB. choose a microcontroller, by serial line interface, the tap position of n DCP is controlled.

The method of raising DCP resistance adjustment resolution of the present invention, in described step a, the tap terminals R of n DCP _WAll connect together as the tap terminals R of equivalent DCP _WE, the RL end of n DCP all connects together as the low side R of equivalent DCP _LE, the R of n DCP _HHold all unsettled; In described step b, the tap position that MCU controls each DCP changes, and guarantees that the tap of each DCP is in same position all the time.

The method of raising of the present invention DCP resistance adjustment resolution, the quantity n of DCP used is desirable greater than 1 positive integer.N DCP is in parallel, makes the resistance adjustment stepping value of equivalent DCP become the n of single DCP/one, and resistance adjustment resolution improves greatly.

Correspondingly, in order to overcome the shortcoming of above-mentioned technical matters, the invention provides the circuit that a kind of circuit is simple, control improves DCP resistance adjustment resolution flexibly.

The circuit of raising DCP resistance adjustment resolution of the present invention comprises microcontroller, a n same model DCP; N DCP connects with parallel form, consists of an equivalent DCP; The R of n DCP _HHold all unsettled, the tap terminals R of n DCP _WAll connect together as the tap terminals R of equivalent DCP _WE, the R of n DCP _LEnd all connects together as the low side R of equivalent DCP _LEThe tap position that MCU controls each DCP changes, and guarantees that the tap of each DCP is in same position all the time.The quantity n of DCP used is desirable greater than 1 positive integer.

The invention has the beneficial effects as follows: in parallel by adopting a plurality of same model DCP chips, under the prerequisite that does not change the total tap number of DCP, the smallest incremental value of resistance adjustment is reduced greatly, thereby improved the resistance step-by-step adjustment resolution of DCP, expanded the range of application of DCP.

Description of drawings

Accompanying drawing is electric theory diagram of the present invention.

In figure: 1MCU, 2 the 1st digital regulation resistance DCP1,3 the 2nd digital regulation resistance DCP2,4 a n digital regulation resistance DCPn.

Embodiment

By reference to the accompanying drawings, the method for raising of the present invention DCP resistance adjustment resolution, carry out according to following steps: a. chooses n same model digital regulation resistance DCP chip, and the resistance side of this n DCP is connected with parallel form, consists of an equivalent DCP; If the all-in resistance of each DCP is R _T, tap number is that t, tap position are i, the variable resistance of equivalent DCP is R _EB. choose a microcontroller, by serial line interface, the tap position of n DCP is controlled.

In the method for above-mentioned raising DCP resistance adjustment resolution, the tap terminals R of n DCP _WAll connect together as the tap terminals R of equivalent DCP _WE, the R of n DCP _LEnd all connects together as the low side R of equivalent DCP _LE, the R of n DCP _HHold all unsettled; The tap position that MCU controls each DCP changes, and guarantees that the tap of each DCP is in same position all the time.The quantity n of DCP used is desirable greater than 1 positive integer.

As shown in drawings, provided the circuit of raising DCP resistance adjustment resolution of the present invention, it comprises MCU (1), first digit potentiometer DCP1 (2), second digit potentiometer DCP2 (3), a n digital regulation resistance DCPn (4).Shown n digital regulation resistance DCP model is identical, equivalent DCP of this n DCP formation in parallel; DCP1 (2), DCP2 (3) ... the R of DCPn (4) _WEnd is connected in parallel as the tap terminals R of equivalent DCP _WE, DCP1 (2), DCP2 (3) ... the R of DCPn (4) _LEnd is connected in parallel as the low side R of equivalent DCP _LEMCU (1) controls each DCP tap R by serial line interface _WChange in location, the tap of each DCP is in same position all the time.Like this, the tap resistance of equivalent DCP is namely the parallel connection of all DCP tap resistance.By equivalent DCP circuit is analyzed, can draw its variable resistance R _EFor:

$R_E=\frac{R_T}{n(t-1)}\×i---\left(1\right)$

The resistance adjustment stepping value of single DCP is:

$\mathrm{\Δ}=\frac{R_T}{(t-1)}---\left(2\right)$

The resistance adjustment stepping value of equivalence DCP becomes:

$\mathrm{\Δ}=\frac{R_T}{n(t-1)}---\left(3\right)$

The resistance adjustment stepping value of equivalence DCP is the n/of single DCP, and resistance step-by-step adjustment resolution improves greatly.

Claims (4)

1. a method that improves DCP resistance adjustment resolution, is characterized in that, comprises the following steps:

A. choose n same model digital regulation resistance DCP, this n DCP is connected with parallel form, consist of an equivalent DCP; If the all-in resistance of each DCP is R _T, tap number is that t, tap position are i, the variable resistance of equivalent DCP is R _E

B. choose a microcontroller, by serial line interface, the tap position of n DCP is controlled.

2. the method for raising according to claim 1 DCP resistance adjustment resolution is characterized in that: in described step a, and the tap terminals R of n DCP _WAll connect together as the tap terminals R of equivalent DCP _WE, the R of n DCP _LEnd all connects together as the low side R of equivalent DCP _LE, the R of n DCP _HHold all unsettled; In described step b, the tap position that MCU controls each DCP changes, and guarantees that the tap of each DCP is in same position all the time; The quantity n of DCP used is desirable greater than 1 positive integer.

3. a circuit that improves DCP resistance adjustment resolution, comprise microcontroller, a n same model DCP, and it is characterized in that: n DCP connects with parallel form, consists of an equivalent DCP; The R of n DCP _HHold all unsettled, the tap terminals R of n DCP _WAll connect together as the tap terminals R of equivalent DCP _WE, the R of n DCP _LEnd all connects together as the low side R of equivalent DCP _LEThe tap position that MCU controls each DCP changes, and guarantees that the tap of each DCP is in same position all the time.

4. the circuit of raising according to claim 3 DCP resistance adjustment resolution is characterized in that: the quantity n of DCP used is desirable greater than 1 positive integer.

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