JPH0399506A - Selective input type amplification factor switching amplifier - Google Patents

Abstract

PURPOSE:To share an amplifier to reduce the mounting space by interlocking selection of plural input lines and switching of the amplification factor of the amplifier with each other. CONSTITUTION:A switch 12 is controlled by a switch control part 14 to select input lines 7a to 7c of sensors 3a to 3c of an input part 7, and simultaneously, a switch 13B of an amplification factor switching amplifying part 13 is controlled and feedback resistances 13a to 13d of an amplifier 13A are selected in accordance with selected sensors 3a to 3c to control the amplification factor of the amplifier 13A, and the amplification output of the amplifying part 13 dependent on sensors 3a to 3c is fixed. By this constitution, one amplifier is shared among different sensors, and the mounting space of a selective input type amplification factor switching amplifier is reduced to obtain an economical device.

Description

[Detailed Description of the Invention] [Summary] This invention relates to an amplifying device that receives and amplifies multi-channel voltage input, and in particular, a method for making amplified output voltages in the same range when the input voltage ranges from each channel are different. Regarding selective input type amplification factor switching type amplifiers, the purpose of this is to allow multiple signals to be converted into the same voltage range with one amplifier, thereby reducing mounting space and device costs. a plurality of input lines for inputting a plurality of signals having , a switch for selecting one of these input lines, and an amplification factor switching type amplifier for amplifying the signal from the input line selected by the switch. In addition, a control means is provided for switching the selection of the input line by the switch and the amplification factor of the amplifier in conjunction with each other so that the signal from any input line is output as a signal having approximately the same voltage range even when the signal is input to the amplifier. Establish and configure.

[Industrial Application Field] The present invention relates to an amplifying device that receives and amplifies multi-channel voltage input, and particularly relates to an amplifier device that receives and amplifies multi-channel voltage input. The present invention relates to a selective input type amplification factor switching type amplifier.

[Prior Art] In general, a monitoring system, for example, a system in which air conditioning of a building or the like is managed and monitored by a master station other than the building, is configured as shown in FIG. 3. In other words, each building 1 to be monitored is provided with a terminal device 2, and this terminal device 2
Detection signals (analog signals) are input as voltages from various sensors 3a to 3c arranged at various locations in the building 1 to detect temperature and the like. The terminal device 2 is connected to a master station 6 via a line 5 controlled by the CPU 4, and the detection results from each sensor 3a to 3C input to the terminal bag Wt2 are transmitted to the master station 6 via the line 5. digitally transmitted.

At this time, the terminal device 2 receives detection signals from the various sensors 3a to 3C, but the range of the input voltage that is the detection signal may differ depending on the sensor.

The input detection signal is A/D converted and sent to the master station 6, but when inputting the detection signal to the A/D converter (not shown) in the terminal device 2, the input signals are of the same voltage. If it is not within this range, the A/D converter will not work properly.

Therefore, in the case where the input voltage range differs for each channel due to the characteristics of each sensor 3a to 3C, in order to make the voltages in the same voltage range, an amplifier device as shown in FIG. It is located within 2.

FIG. 4 is a circuit diagram showing a conventional amplifier device. In this FIG. 88-8c are amplifiers that amplify and output the signals from human power N1A7a-7C, respectively, and 9a-9f are amplifiers 8a-8c. amplification factor A
1 to A, and the amplification factor A of the amplifier 8a is set to (R+R
, )/R, and a resistor 9c with a resistance value R,,R.

9d, the amplification factor A2 of the amplifier 8b is (R+R2)/R
The amplification factor A3 of the amplifier 8C is set to (R+R,)/R by the resistors 9e and 9f with resistance values R, , R, but each amplification factor A, ~A, is connected to the input line. 78
It is set so that signals having different voltage ranges from 7c to 7c are output as signals having substantially the same voltage range.

Further, 10 receives the amplified signals from each of the amplifiers 8a to 8C and switches/selects any one of these signals to A.
A switch 11 for sending data to a /D converter (not shown), etc. is a switch control unit that controls the switching operation of this switch 10.

With the above configuration, detection signals of different voltage ranges from the sensors 3a to 3C are input to the amplifiers 88 to 8C through three channels, that is, input lines 7a to 7c, respectively, and in each amplifier 88 to 8C, the resistance 9a is ~9f
The signal is amplified at a predetermined increase rate set by , and is converted into a signal having approximately the same voltage range and output. The three types of signals amplified and converted in this manner are input to the switch 10, and are outputted from the switch 10 in a time-sharing manner by switching the switch 10 by the switch control section 11.

[Problem to be Solved by the Invention] However, in such a conventional amplifier device, when signals having different voltage ranges are inputted to each input line (channel) 7a to 7c, each input line 7a to 7c has a different voltage range. Amplifiers 8a to 8c must be provided in the circuit, which requires a large mounting space and increases the cost required for the device.The problem is that the larger the number of input signals, the more mounting space and cost are required. be.

The present invention aims to solve such problems,
1g more! By using an I-switching type amplifier, multiple signals can be converted into the same voltage range with one amplifier, reducing mounting space and device costs.Selective input type amplification rate switching type amplifier. The purpose is to provide equipment.

[Means for resolving issues] FIG. 1 is a block diagram of the principle of the present invention.

In FIG. 1, as in the conventional case, 38 to 3C are sensors that output a plurality of (three types in this case) detection signals each having a different voltage range, and 7 is one of these sensors 3a to 3C.
7a to 7C are sensors 3a to 3C, respectively.
Input line for inputting detection signals of different voltage ranges from
channel).

Further, 12 is a switch for selecting one of the input lines 7a to 7C, and 13 is an input line 7 selected by this switch 12.
An amplification factor switching type amplification section that amplifies the signal from 8 to 7c,
This amplifying section 13 includes an amplifier 13A, a switch 13B, and resistors 13a to 13d. The amplifier 13A amplifies the signal selected by the switch 12, and the amplification factor of the amplifier 13A is determined by the resistors 13a to 13.
d, and can be switched by switch 13B. In other words, the switch 13B switches the amplification factor by selecting one of the resistors 13b to 13d. When the resistor 13b is selected, the amplification factor of the amplifier 13A is determined by the resistors 13a and 13b with resistance values R and R□. (R+R,)/R(=A,), and if you select the resistor 13c, the resistance value R2R2 becomes (R+R2)/R(=A,) due to the resistors 13a and 13c, and if you select the resistor 13d, The resistance values R, R, and the resistors 13a and 13d result in (R+R3)/R(=A 3 ). These amplification factors A~A are set by determining resistance values so that signals having different voltage ranges from the input lines 78~7C are output as signals having approximately the same voltage range.

Further, reference numeral 14 denotes a switch control unit (control means), which controls the input lines of the switch 12 so that no matter which of the input lines 78 to 7C the signal is input to the amplification unit 13, the signal is output as a signal in almost the same voltage range. 78 to 7c and the amplification factor of the amplifier 13A in the amplifying section 13 (switch 13B
(selection of resistors 13b to 13d).

[Function] With the above-described configuration, detection signals in different voltage ranges from the sensors 3a to 3C are input to the switch 12 through the input lines 7a to 7c, respectively, and one of the three signals is input to the switch 12 through the input lines 7a to 7c.
is selected and input to the amplifying section 13.

In the amplifying section 13, in conjunction with the selection of the input lines 7a to 7C by the switch 12, the switch 13B switches and selects the resistors 13b to 13d, and the amplification factor of the amplifier 13A is set to the selected input line. It can be switched from A to A according to the input voltage range of 7a to 7C. Switching control of the switches 12 and 13B is performed by the switch control section 14.
This is done by

This allows the amplifier 13A to be used for different input voltage ranges.
The amplification factor of the amplification section 13 can be switched, and the output from the amplification section 13 can be made to be within approximately the same voltage range.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 2 is a circuit diagram showing one embodiment of the present invention.

In this embodiment, as in the conventional case, in a building management system as shown in FIG. If provided,
An amplification device used to bring the signals from each sensor 3a to 3C into the same voltage range (for example, ±10v) will be described.

Each sensor 3a to 3C in the input section 7 is connected to an input line 7a to 7c.
(CHI, CH2, CH3, respectively) are connected to the switch 12. This switch 12 is composed of three switching elements 12a to 12c connected to input lines 7a to 7C, respectively, and by turning on (closed) one of these switching elements 12a to 12C, This selects one of the input lines 7a to 7c.

Further, the switch 12 is connected to an amplification factor switching type amplification section 13, and in this amplification section 13, signals from the input lines 78 to 7C selected in a time-division manner by the switch 12 are amplified. ing. The amplification unit 13 includes an amplifier ↑3A that amplifies the signal selected by the switch 12, and a switch 13 that switches the amplification factor of this amplifier 13A.
B, and resistors 13a to 1 that set the amplification factor of the amplifier 13A.
It is composed of 3d.

Here, the switch 13B has resistors 13b to 13, respectively.
Three switching elements 13e to 13g connected to d
These switching elements 13e to 13
By turning on (closed) one of resistors 13b to 13d, one of the corresponding resistors 13b to 13d is selected to switch the amplification factor. When the resistor 13b is selected, the amplification factor of the amplifier 13A is the resistor 13a with resistance values R and R1.

13b becomes (R+R,)/R(=A,), and if resistor 13c is selected, resistor 13a with resistance value R, R,
, 13c becomes (R+R2)/R (=A,), and if resistor 13d is selected, resistor 13a with resistance values R, R,
, 13d, it becomes (R+R3)/R(=A3). In this embodiment, these amplification factors (gains) of 80 to A3 are:
Voltage ranges ±IV, ± from input lines 78 to 7c, respectively.
5V and ±10V signals have the same voltage range ±10V, respectively.
The resistance values are determined and set to be 10 times, 2 times, and 1 times so that it is output as a signal of v. Therefore,
When the switching element 13e is on, the amplification factor is 10 times, when the switching element 13f is on, the amplification factor is 2 times, and when the switching element 13g is on, the amplification factor is 1 time.

Furthermore, each switch 12.13 has a switch control unit (
Control means) 14 is connected, and control signals A, B, and C2D from this switch control section 14 are sent to switches 12 and 13 through 2-bit signal lines, respectively.

Then, the switch control unit 14 controls which of the input lines 78 to 78
Even when the signal from 7c is input to the amplifying section 13, the input line 7 is connected to the switching elements 12a to 12c of the switch 12 in order to output it as a signal in the same voltage range ±IOV.
Select from a to 7c.

The amplification factor of the amplifier 13A in the amplifying section 13, that is, the selection of the resistors 13b to 13d by the switching elements 13e to 13g of the switch 13B, is switched in conjunction with the selection of the resistors 13b to 13d.

The control signals A and B sent to the switch 12 are, for example, given as 0.1 data as shown in Table 1 below to select the input lines 7a to 7c (CH2-CH2), while the switches], 3B The control signals C and D sent to are also 1, for example,
As shown in Table 2 below, the resistances 13b to 13d are given as 0.1 data, that is, the amplification factor (gain) is 10 times, 2 times,
1x is selected. In addition, switch 12
The control signal is A so that A and switch 13B are linked.
=C.

It is output as B=D.

In addition, the switching element 12a of the switch 12.13B
As ~12e and 13e~13g, analog switches or relay switches are used.

With the above configuration, detection signals of different voltage ranges from the sensors 3a to 3c are input to the switch 12 through three channels, that is, input lines 78 to 7c, respectively.
In this switch 12, signals from input lines 78 to 7c selected by control signals A and B from the switch control section 14 are input to the amplification section 13.

In the amplifier section 13, in conjunction with the selection of the inputs IIA7a to 7c by the switch 12, the switch 13B receives control signals C and D from the switch control section 14 to switch and select the resistors 13b to 13d. The increase rate of the amplifier 13A is changed according to the input voltage range of the selected input lines 78 to 7c.

That is, in this embodiment, when the input line 7a is selected, a signal with a voltage range of ±1■ is input, so that the switching element 1
3e is turned on, the amplification factor is increased to 10 times, and the input line 7b is turned on.
When selecting, a signal of 5V above the voltage range is input, so
The switching element 13f is turned on and the amplification factor is doubled, and when the input line 7c is selected, a signal in the voltage range of ±1 V is input, so the switching element 13g is turned on and the amplification factor is doubled.

This allows for different input voltage ranges ±IV, ±5V, ±1
With respect to 0V, the amplification factor of the amplifier 13A is switched to 10 times, 2 times, and 1 time, respectively, and the output from the amplifier section 13 can be kept within the same voltage range of ±10V.

As described above, according to the selective input type amplification factor switching type amplifier of this embodiment, the amplification factor of the amplifier 13A is automatically switched and controlled according to the voltage range of the signals input from the input lines 78 to 7c. Therefore, a plurality of signals can be converted into the same voltage range by one amplifier 13A, and the amplifier 13A can be shared, and the mounting space and device cost can be reduced significantly.

Note that in the above-described embodiment, a case has been described in which there are three input lines, that is, three signals having different voltage ranges are input, but the present invention is not limited to this. Further, in the above embodiment, a case has been described in which the detection signals from the sensors 3a to 3c of the building management system are amplified, but the present invention is not limited to this, and the present invention can be applied to The same applies to various cases in which it is necessary to convert a signal into a signal having approximately the same voltage range.

[Effects of the Invention] As detailed above, according to the selective input type amplification factor switching type amplifier of the present invention, the amplification factor of the amplifier can be automatically adjusted according to the voltage range of signals input from a plurality of input lines. It is configured so that multiple signals can be switched and controlled and converted into the same voltage range with one amplifier, so the amplifier can be shared, greatly reducing the mounting space and equipment cost. It has the advantage of being able to reduce

[Brief explanation of drawings]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a circuit diagram showing an embodiment of the present invention, Fig. 3 is a block diagram showing a general building management system, and Fig. 4 is a block diagram of a conventional amplification device. FIG. In the figure, 3a to 3c are sensors, 7 is an input section, and 7a to 7c are input lines. 12 is a switch. 12a to 12c are switching elements, 13 is an amplification factor switching type amplifier, 13A is an amplifier, 13B is a switch, 13a to 13d are resistors, 13e to 13g are switching elements, and 14 is a switch control unit (control means).

Claims (1)

[Claims] A plurality of input lines (7a to 7c) for inputting a plurality of signals having different voltage ranges, a switch (12) for selecting one of these input lines (7a to 7c), Input lines (7a to 7c) selected by the switch (12)
An amplification factor switching type amplifier (13) is provided to amplify the signal from the amplifier (13), and the signal from any of the input lines (7a to 7c) is
13), the switch (12) switches the input line (
7a to 7c) and a control means (14) for switching the amplification factor of the amplifier (13) in conjunction with each other.