JPH0517606Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention performs reference point compensation,
This invention relates to a recorder that records detected values by performing linearization and the like.

[Prior Art] When recording a detection value, it is necessary to remove noise and the like contained in the detection signal before processing the detection signal obtained by a detector.

The configuration of this type of conventional recorder is shown in FIG.

FIG. 2 is a configuration diagram of a conventional recorder. In the figure, 31 is a hard filter that extracts only signals in a certain frequency band from the detection signal S, and 11 is a hard filter that extracts only signals in a certain frequency band from the detection signal S.
12 is a hard filter 3
Shift voltage variable means adjusts the voltage applied to the differential amplifier 11 in order to compensate for the reference point of the detection signal S that has passed through the detection signal S; 13 changes the amplification factor of the differential amplifier 11 in order to adjust the range of the detection signal S; 21 is a stacked A/D converter that converts the detection signal S consisting of an analog signal amplified by the differential amplifier 11 into a digital signal; 4 is a stacked A/D converter that converts the detected signal S to a digital signal; A processing unit processes the detection signal S consisting of a digital signal to perform reference point compensation, range setting, scaling, linearization, etc.; 5 is a recorder for recording detection values based on the detection signal processed by the processing unit 4; It is a means.

Next, the operation of the conventional recorder configured as described above will be explained.

First, the detection signal is converted into only a signal in a certain frequency band by the hard filter 31, and is amplified in the differential amplifier 11 based on the amplification factor set by the gain variable means 13.
is output to.

At this time, the reference voltage applied to the differential amplifier 11 is adjusted by the shift voltage variable means 12.

The detection signal input to the stacked A/D converter 21 is converted into a digital signal and input to the processing section 4. The processing unit 4 processes the detection signal S to perform linearization, reference point compensation, range adjustment, scaling, etc.

Further, based on the detection signal S processed by the processing section 4, the recording means 5 records the detection value.

Here, the stacked A/D converter 21 and the hard filter 31 serve to remove noise and the like from the detection signal S.

[Problems that the invention attempts to solve] However, in conventional recorders, A/D
A stacked A/D converter is used as a converter,
Conversion time was extremely long.

Furthermore, since a hard filter constructed as a hardware was used as a filter, there was a drawback that frequency characteristics were impaired.

This invention was made to solve the above problems, and the purpose is to obtain a recorder that has good noise characteristics and can perform analog-to-digital conversion at high speed.

[Means for solving the problem] Therefore, the recorder according to this invention amplifies the detection signal with an amplifier that can vary the shift voltage and gain, converts the amplified signal from analog to digital, and converts the amplified signal from analog to digital. In a recorder that records a detection value based on the above detection signal using a recording means after processing such as point compensation, linearization, and range switching, a successive approximation type A/D converter converts the detection signal amplified by an amplifier from analog to digital. It is characterized by comprising a D converter and a soft filter that extracts only a detection signal in a certain frequency band into which the digital signal output from the A/D converter is input.

[Operation] The successive approximation type A/D converter according to this invention converts a detection signal consisting of an analog signal amplified by an amplifier into a digital signal.

This converted digital signal is input to a soft filter, and the soft filter outputs only signals in a certain frequency band from this digital signal.

[Embodiment] An embodiment of the present invention will be described below based on the drawings.

Note that the same components as in the prior art are given the same numbers and their explanations are omitted. FIG. 1 is a block diagram of a recorder showing an embodiment of the present invention. In the figure, 2 is a successive approximation type A/D converter, and 3 is a digital signal output from the successive approximation type A/D converter 2. This is a soft filter that extracts only signals in a certain frequency band.

Here, the soft filter 3 is a digital filter that is processed by software so as to perform a predetermined operation on the digital signal and extract only signals in a certain frequency band. To explain further, this digital filter removes high-frequency noise by constructing a first-order lag low-pass filter using a calculation using a difference equation. Filter output value
FVn-1, current filter input value is PV, filter coefficient is KF, FVn=FVn-1+KF
It can be expressed as (PV-FVn-1).

Next, the operation of one embodiment of the present invention configured as described above will be explained.

First, the detection signal S amplified by the amplifier 11 is input to the successive approximation type A/D converter 2, where it is converted into a digital signal. Successive approximation type A/D
The digital signal converted by the converter 2 is input to the soft filter 3, where only digital signals in a certain frequency band are extracted and output to the processing section 4.

In addition, in this invention, when performing linearization etc., the amount of data required for linearization increases and memory capacity is required, but this can be sufficiently overcome due to recent increases in memory capacity and lower prices. can.

[Effects of the invention] As stated above, this invention has the successive approximation form A/
Since noise is removed using a D converter and a soft filter, the noise characteristics are good.
A recorder that can process at high speed can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a recorder showing an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional recorder. 2... Successive approximation meter A/D converter, 3... Soft filter, 4... Processing section, 5... Recording means, 11
...Differential amplifier.

Claims (1)

[Claims for Utility Model Registration] The detection signal is amplified with an amplifier that can vary the shift voltage and gain, and the amplified signal is converted into an analog
In a recorder that records a detection value based on the above detection signal in a recording means after converting it into digital data and performing processing such as reference point compensation, linearization, and range switching in a processing section, the detection signal amplified by an amplifier is converted from analog to digital. A record characterized by comprising a successive approximation type A/D converter for conversion, and a soft filter for inputting a digital signal output from the A/D converter and extracting only detection signals in a certain frequency band. Total.