Level-adjustable output system for RS232 serial communication card

Abstract

The invention provides a level-adjustable output system for an RS232 serial communication card, which belongs to the technical field of serial communication cards and comprises an upper computer communication interface, a transceiver chip, a master controller, a data buffer, a high-level DAC (digital-to-analog converter), a filter, a buffer amplifier, a TVS (transient voltage suppressor) protector, a low-level DAC and a push-pull driving stage. The level adjustable output system for the RS232 serial port communication card provides a stable, reliable and flexible solution for RS232 serial port communication through the characteristics of accurate level adjustment, enhanced anti-interference capability, efficient data transmission, strong driving capability, comprehensive protection mechanism and easy integration and maintenance.

Description

Technical Field

[0001] The invention relates to the field of serial port communication cards, in particular to a level-adjustable output system for RS232 serial port communication cards. Background Art

[0002] In the existing RS232 serial communication, the level-adjustable output structure has the following problems:

[0003] Incompatible levels: The RS232 standard defines specific voltage ranges (usually +3V to +15V for logic "0" and -3V to -15V for logic "1"). If the adjustable output structure is not accurately adjusted to these voltage ranges, it may cause unstable or failed communications with other devices.

[0004] Output stability: Level-adjustable outputs may introduce noise or instability when adjusting the voltage, especially when the load changes. If the output level is unstable, it may cause bit errors during data transmission.

[0005] Response time: The level-adjustable output structure may have a delay when adjusting the level, which is a problem for serial communication that requires a fast response. Especially in the case of high-frequency data transmission, the delay in response time may affect the overall communication efficiency.

[0006] Current output capability: RS232 communication usually requires a certain current output capability. If the current output capability of the level-adjustable output structure is insufficient, it may cause signal attenuation and affect the reliability of long-distance transmission.

[0007] Overheating: When working at high load for a long time, the level-adjustable output structure may overheat, resulting in performance degradation or failure. A reasonable heat dissipation solution needs to be designed.

[0008] Electrical isolation: Lack of proper electrical isolation may result in ground loop problems between different devices, causing signal interference or damaging the equipment.

[0009] Therefore, there is an urgent need in the art for a level-adjustable output system for an RS232 serial port communication card that can solve one or more of the above problems.

[0010] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0011] The purpose of the present invention is to provide a technical solution with level compatibility, stable output, low response delay, strong current output capability, good heat dissipation and electrical isolation.

[0012] To achieve the above object, the present invention provides the following solutions:

[0013] A level-adjustable output system for an RS232 serial port communication card, comprising:

[0014] Host computer communication interface, transceiver chip, main control, data buffer, high-level DAC, filter, buffer amplifier, TVS protector, low-level DAC and push-pull driver stage;

[0015] The host computer communication interface is connected to the transceiver chip, the transceiver chip is connected to the main control, the main control is respectively connected to the data buffer, the high level DAC, the low level DAC and the push-pull drive stage, the high level DAC and the low level DAC are respectively connected to the filter, the filter is connected to the buffer amplifier, the buffer amplifier is connected to the TVS protector, and the TVS protector is connected to the push-pull drive stage.

[0016] Optionally, the host computer communication interface is used for communication between the board and the host computer, using PCI, PCIe, CPCI, PXIe, USB and Ethernet interface methods.

[0017] Optionally, the transceiver chip is used to convert the host computer interface protocol into an interface that can be recognized by the main control device.

[0018] Optionally, the main control is an FPGA or a high-speed single-chip microcomputer, which is used to parse host computer instructions and receive data set by the host computer to be sent. The main control is also used to control DAC and adjust the output level.

[0019] Optionally, when the master control sending logic is idle, the data to be sent from the host computer will be sent directly through the output stage. When the sending logic is busy, the received data will be temporarily stored in the data cache module and sent out when the board is idle.

[0020] Optionally, the high-level DAC and the low-level DAC are used to generate high-level and low-level voltage values ​​for serial port output respectively, and the high-level DAC and the low-level DAC are controlled by a main control chip, and the specific set voltage values ​​are issued by a host computer.

[0021] Optionally, the filter can filter out most of the noise output by the DAC and provide level stability;

[0022] The TVS protector is used to protect the buffer amplifier from being affected by the external surge signal.

[0023] The buffer amplifier is used to provide a level voltage with driving capability for push-pull driving.

[0024] Optionally, the push-pull driving stage uses two upper and lower MOS tubes as output switches, and a three-state controller is provided in front of the MOS tube. The output of the three-state controller is controlled by a level control signal given by the main control, and the three-state controller controls the MOS tube to be turned on or off;

[0025] The master controller gives an enable control signal to control whether this output is enabled;

[0026] When the upper MOS tube is turned on, it outputs a high level, and the voltage is the output voltage of the high-level DAC and buffer amplifier.

[0027] When the lower MOS tube is turned on, it outputs a low level, and the voltage is the output voltage of the low-level DAC and buffer amplifier.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The present invention provides a level-adjustable output system for an RS232 serial communication card, comprising: a host computer communication interface, a transceiver chip, a main control, a data buffer, a high-level DAC, a filter, a buffer amplifier, a TVS protector, a low-level DAC and a push-pull driver stage;

[0030] 1. Communication and data processing

[0031] Stable data transmission:

[0032] The host computer communication interface ensures the connection with external devices (such as computers and other host computer devices) and provides a channel for data input and output. The transceiver chip is responsible for converting between different level standards to ensure the normal RS232 serial communication.

[0033] The master controller controls the entire system and coordinates the work of each component. The data buffer can temporarily store data to avoid loss or congestion during data transmission, thereby improving the stability and reliability of data transmission.

[0034] Flexible level control:

[0035] The existence of high-level DAC and low-level DAC enables the system to adjust the output level. This is very useful in different application scenarios. For example, when communicating with external devices with different level requirements, the DAC output level can be adjusted to match the input level requirements of the external device.

[0036] 2. Signal quality

[0037] Signal filtering and amplification:

[0038] The filter can filter the output signal, remove the noise and interference components in the signal, and improve the purity of the signal. The buffer amplifier can amplify the filtered signal and enhance the signal strength so that it can better drive external devices.

[0039] Protection function:

[0040] TVS protectors can protect the system from instantaneous high voltage pulses (such as those caused by electrostatic discharge, electromagnetic interference, etc.) causing damage to the system, thereby improving the stability and reliability of the system and extending the service life of the system.

[0041] 3. Driving capability

[0042] The push-pull driver stage can improve the output drive capability of the system, enabling it to better drive the load. For example, when the connected external device has certain requirements for the driving current of the input signal, the push-pull driver stage can provide sufficient current to meet the requirements, ensuring that the data can be accurately transmitted to the external device. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0044] Figure 1 A schematic diagram of the system structure provided by an embodiment of the present invention.

[0045] Figure 2 A schematic diagram of a push-pull driving stage structure provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] The purpose of the present invention is to provide a technical solution with level compatibility, stable output, low response delay, strong current output capability, good heat dissipation and electrical isolation.

[0048] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0049] Embodiment 1:

[0050] This embodiment provides a level-adjustable output system for an RS232 serial communication card, such as Figure 1 As shown, including:

[0051] Host computer communication interface, transceiver chip, main control, data buffer, high-level DAC, filter, buffer amplifier, TVS protector, low-level DAC and push-pull driver stage;

[0052] The host computer communication interface is connected to the transceiver chip, the transceiver chip is connected to the main control, the main control is respectively connected to the data buffer, the high level DAC, the low level DAC and the push-pull drive stage, the high level DAC and the low level DAC are respectively connected to the filter, the filter is connected to the buffer amplifier, the buffer amplifier is connected to the TVS protector, and the TVS protector is connected to the push-pull drive stage.

[0053] Furthermore, the host computer communication interface is used for communication between the board and the host computer, and adopts PCI, PCIe, CPCI, PXIe, USB and Ethernet interface methods.

[0054] Furthermore, the transceiver chip is used to convert the upper computer interface protocol into an interface that can be recognized by the main control device.

[0055] Furthermore, the main control is an FPGA or a high-speed single-chip microcomputer, which is used to parse the host computer instructions and receive the data set to be sent by the host computer. The main control is also used to control the DAC and adjust the output level.

[0056] Furthermore, when the master control sending logic is idle, the data to be sent from the host computer will be sent directly through the output stage. When the sending logic is busy, the received data will be temporarily stored in the data cache module and sent out when the board is idle.

[0057] Furthermore, the high-level DAC and the low-level DAC are used to generate high-level and low-level voltage values ​​for serial port output respectively. The high-level DAC and the low-level DAC are controlled by the main control chip, and the specific set voltage values ​​are issued by the host computer.

[0058] Furthermore, the filter can filter out most of the noise output by the DAC and provide level stability;

[0059] The TVS protector is used to protect the buffer amplifier from being affected by the external surge signal.

[0060] The buffer amplifier is used to provide a level voltage with driving capability for push-pull driving.

[0061] Further, such as Figure 2 As shown, the push-pull driving stage uses two MOS tubes as output switches, and a three-state controller is provided in front of the MOS tube. The output of the three-state controller is controlled by a level control signal given by the main control, and the three-state controller controls the MOS tube to be turned on or off;

[0062] The master controller gives an enable control signal to control whether this output is enabled;

[0063] When the upper MOS tube is turned on, it outputs a high level, and the voltage is the output voltage of the high-level DAC and buffer amplifier.

[0064] When the lower MOS tube is turned on, it outputs a low level, and the voltage is the output voltage of the low-level DAC and buffer amplifier.

[0065] By designing appropriate DAC and buffer amplifier, the output high level can be configured in the range of 0V to 18V, and the low level can be configured in the range of -18V to 0V. It can cover the RS232 level standard and provide voltage over-limit pull-off capability.

[0066] By configuring appropriate MOS tubes, the ±18V output capability can be met.

[0067] The board obtains power from the outside through the power interface, and converts it into the voltage required by each module of the board through the voltage conversion device inside the board.

[0068] One master controller can drive the output of multiple serial ports.

[0069] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0070] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A level-adjustable output system for RS232 serial communication card, characterized in that: include: Host computer communication interface, transceiver chip, main control, data buffer, high-level DAC, filter, buffer amplifier, TVS protector, low-level DAC and push-pull driver stage; The host computer communication interface is connected to the transceiver chip, the transceiver chip is connected to the main control, the main control is respectively connected to the data buffer, the high level DAC, the low level DAC and the push-pull drive stage, the high level DAC and the low level DAC are respectively connected to the filter, the filter is connected to the buffer amplifier, the buffer amplifier is connected to the TVS protector, and the TVS protector is connected to the push-pull drive stage.

2. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: The host computer communication interface is used for communication between the board and the host computer, and adopts PCI, PCIe, CPCI, PXIe, USB and Ethernet interface methods.

3. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: The transceiver chip is used to convert the upper computer interface protocol into an interface that can be recognized by the main control device.

4. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: The main control is an FPGA or a high-speed single-chip microcomputer, which is used to parse the host computer instructions and receive the data set to be sent by the host computer. The main control is also used to control the DAC and adjust the output level.

5. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: When the master control sending logic is idle, the data to be sent from the host computer will be sent directly through the output stage. When the sending logic is busy, the received data will be temporarily stored in the data cache module and sent out when the board is idle.

6. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: The high-level DAC and the low-level DAC are used to generate high-level and low-level voltage values ​​for serial port output respectively. The high-level DAC and the low-level DAC are controlled by the main control chip, and the specific set voltage values ​​are issued by the host computer.

7. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: The filter can filter out most of the noise output by the DAC and provide level stability; The TVS protector is used to protect the buffer amplifier from being affected by the external surge signal. The buffer amplifier is used to provide a level voltage with driving capability for push-pull driving.

8. The level-adjustable output system for RS232 serial communication card according to claim 1, characterized in that: The push-pull driving stage uses two MOS tubes as output switches, and a three-state controller is placed in front of the MOS tube. The output of the three-state controller is controlled by a level control signal given by the main control, and the three-state controller controls the MOS tube to be turned on or off. The master controller gives an enable control signal to control whether this output is enabled; When the upper MOS tube is turned on, it outputs a high level, and the voltage is the output voltage of the high-level DAC and buffer amplifier. When the lower MOS tube is turned on, it outputs a low level, and the voltage is the output voltage of the low-level DAC and buffer amplifier.

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