JPH02131030A - Data reception circuit - Google Patents

Abstract

PURPOSE:To suppress all input signals up to a receptible level by providing an amplitude limiter on a reception side equipment such as a hybrid transformer in a data reception circuit in a data transmission equipment in which the reception side and the transmission side are separated. CONSTITUTION:When a signal received from a reception winding 40r of a hybrid transformer 40 is at a normal transmission level or below, an amplitude limiter 41 gives a reception signal to a reception section 42 without being operated. Moreover, when the reception signal is at a normal transmission level or over, Zener diodes 41a, 41b of the amplitude limiter 41 are operated. Thus, an excess input signal exceeding the reception capability is limited by the reception section 42 and the reception section 42 is always operated in the optimum state. Thus, the data reception circuit 4 of the amplitude limiter 41 of the simple constitution is operated in the optimum state and data transmission is attained in opposition to the data transmission equipment sending a signal with a level exceeding the conventional transmission level.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data transmission device, and more particularly to a data receiving circuit that makes all input received signals at a receivable level.

[Conventional technology]

Conventionally, this type of data transmission device has a configuration in which a receiving side and a transmitting side are separated by a hybrid transformer or the like connected to a communication line.

Such a data transmission device has a data receiving circuit. This data receiving circuit is configured according to the transmission waveform level of the extensive system of this data transmission device. That is, the data receiving circuit of the conventional data transmission device performs line equalization based on the transmission waveform level of the system. Therefore, when a waveform with a higher level than its own transmission waveform is input to the reception section of the data reception circuit, the reception level exceeds the operating range of the feeder line equalization section, which is abnormally high, and reception becomes impossible.

Furthermore, the input waveform level to the receiving section is defined by the transmission waveform of the system, and the data receiving circuit of the conventional data transmission device operates so that an excessively large input waveform does not need to be treated as a signal.

[Problem to be solved by the invention]

However, recently, in pursuit of improved noise resistance,
It has become necessary to increase the level of the transmitted waveform of the system over that of conventional devices. For this reason, there has been a demand for connecting and using a data transmission device that is currently in operation and a data transmission device that can provide a high level of transmitted waveform.

The present invention has been made to solve the above-mentioned drawbacks, and an object of the present invention is to provide a data receiving circuit that suppresses all input signals to a receivable level.

[Means to solve the problem]

In order to achieve the above object, the data receiving circuit of the present invention is a data receiving circuit in a data transmission device in which a receiving side and a transmitting side are separated by a hybrid transformer or the like connected to a communication line. The device is characterized in that an amplitude limiter is provided on the receiving side of the signal.

According to the present invention, since an amplitude limiter is provided on the receiving side of a high print transformer or the like, it becomes possible to receive waveforms having a higher level than the own received waveform level, which was conventionally impossible to receive.

〔Example〕 Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of the data receiving circuit of the present invention.

In the figure, the data transmission device 2 includes a data receiving circuit 4.
, a transmitter 6 , and a signal processor 8 .

The data receiving circuit 4 includes a high print transformer 40, an amplitude limiter 41 consisting of a Zener diode (418.41b) and a resistor 41r, and a receiving section 42. The hybrid transformer 40 includes a negative winding 40p, a receiving winding 4Or, and a transmitting winding 40t. - The next winding 40p is connected to digital line 1 via terminals Tp and Tm.
Connected to 0. The transmitter winding 40t is connected to the output α;1: of the transmitter 6. The receiving winding 40r is connected to an amplitude limiter 41. The amplitude limiter 41 is configured by connecting a resistor 41r and a series circuit in which Zener diodes 41a and 41b are connected in series in opposite directions in an inverted cursor shape. Zener diode 41 of amplitude limiter 41
Both ends of a and 41b are connected to the input end of the receiving section 42. An output end of the receiving section 42 is connected to the signal processing section 8. The receiving section 42 is required to have the ability to receive input signals in a wide range of levels from the level of the transmitted signal to the minute level attenuated by the intermediate line.

For this reason, the receiving section 42 is designed to extend toward a region where the receiving level is low, and does not guarantee operation for input signals higher than the transmitting level.

Further, the signal processing section 8 is connected to the input end of the transmitting section 6. A signal line 12 for transmitting control, status, etc. is connected to the signal processing unit 8.

The operation of the embodiment configured in this way will be explained.

First, when the signal received from the reception winding 40r of the hybrid transformer 40 is below the normal transmission level, the amplitude limiter 41 provides the reception signal to the reception section 42 without any operation. The receiving section 42 processes the received signal in a predetermined operation and provides it to the signal processing section 8.

On the other hand, if the signal received from the reception winding 40r of the hybrid transformer 40 is higher than the normal transmission level, the amplitude limiter 41 connects the Zener diodes 41a, 41
By operating b, the receiving section 42 is restricted from receiving an excessive input signal that exceeds its reception capability. Thereby, the receiving section 42 always operates in an optimal state.

As described above, according to the present embodiment, the data receiving circuit 4 can be operated in an optimal state with the amplitude limiter 41 having a simple configuration, and the data receiving circuit 4 can be operated in an optimal state, and the amplitude limiter 41 can be operated in an optimal state, and the data receiving circuit 4 can be operated in an optimal state. data transmission.

〔Effect of the invention〕

As explained above, the present invention suppresses the level of all received signals below the level that can be received by the amplitude limiter, so it has the advantage of being able to communicate with all types of data transmission devices. be.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention. 2... Data transmission device, 4... Data receiving circuit, 8... Signal processing unit, 41... Amplitude limiter, 41a, 41b... ... Zener diode, 41
r...Resistance.

Claims (1)

[Claims] A data receiving circuit in a data transmission device in which a receiving side and a transmitting side are separated by a hybrid transformer or the like connected to a communication line, characterized in that an amplitude limiter is provided on the receiving side of the hybrid transformer, etc. receiving circuit.