CN213367755U - RS232 signal isolation passive converter - Google Patents
RS232 signal isolation passive converter Download PDFInfo
- Publication number
- CN213367755U CN213367755U CN202022178305.5U CN202022178305U CN213367755U CN 213367755 U CN213367755 U CN 213367755U CN 202022178305 U CN202022178305 U CN 202022178305U CN 213367755 U CN213367755 U CN 213367755U
- Authority
- CN
- China
- Prior art keywords
- terminal
- diode
- optical coupler
- output
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Electronic Switches (AREA)
Abstract
The utility model relates to a RS232 signal isolation passive converter, which comprises a serial port electricity taking circuit and a signal isolation circuit which are connected between an RS232 input/output terminal A and an RS232 input/output terminal B; the number of the serial port electricity-taking circuits and the number of the signal isolation circuits are two, and the first serial port electricity-taking circuit and the second serial port electricity-taking circuit respectively take electricity from the signal output port of the terminal A or the signal output port of the terminal B and then supply power to the corresponding first signal isolation circuit or the corresponding second signal isolation circuit; the signal isolation circuit comprises a first optical coupler and a second optical coupler, and input ports of the first optical coupler and the second optical coupler are connected with a signal output end of a terminal A/a terminal B; one pin of the output ports of the first and second optocouplers is connected to a high level or a low level, and the other pin is connected to the signal input port of the terminal B/the terminal a. Two opto-couplers realize signal isolation respectively and realize that RS232 signal level superposes about 15V again simultaneously, make product cost reduction, product size reduce.
Description
Technical Field
The utility model relates to a communication circuit field, concretely relates to passive converter is kept apart to RS232 signal.
Background
The RS232 interface has a high signal level value, cannot be hot plugged, and is easy to damage a chip of the interface circuit, so that the RS232 led out from the computer mainboard is frequently damaged when the RS232 interface equipment is used, and therefore, protective measures need to be taken.
In the prior art, an RS232 signal is generally converted into a TTL level chip, and the TTL is converted into the RS232 signal chip after optical coupling isolation. The voltage of any signal line of the RS232 interface is in a negative logic relation, and is not compatible with a TTL level, so that a level conversion circuit is required to be connected with the TTL circuit. The whole insulation apparatus is costly and the product size is large.
SUMMERY OF THE UTILITY MODEL
The utility model discloses to the technical problem who exists among the prior art, provide a passive converter is kept apart to RS232 signal.
The utility model provides an above-mentioned technical problem's technical scheme as follows: an RS232 signal isolation passive converter comprising: the serial port power-taking circuit and the signal isolation circuit are connected between the RS232 input and output terminal A and the RS232 input and output terminal B;
the number of the serial port electricity-taking circuits and the number of the signal isolation circuits are two, and the first serial port electricity-taking circuit and the second serial port electricity-taking circuit respectively take electricity from the signal output port of the terminal A or the signal output port of the terminal B and then supply power to the corresponding first signal isolation circuit or the corresponding second signal isolation circuit;
the signal isolation circuit comprises a first optical coupler and a second optical coupler, and input ports of the first optical coupler and the second optical coupler are connected with a signal output end of the terminal A/terminal B; one pin of the output ports of the first optical coupler and the second optical coupler is connected with the high level or the low level, and the other pin of the output ports of the first optical coupler and the second optical coupler is connected with the signal input port of the terminal B/terminal A.
The utility model has the advantages that: two opto-couplers realize signal isolation respectively and realize that RS232 signal level superposes about 15V again simultaneously, make product cost reduction, product size reduce.
On the basis of the technical scheme, the utility model discloses can also do following improvement.
Further, in the input port of the first optical coupler, the anode of the light emitting diode is connected with the signal output end of the terminal A/terminal B, and the cathode of the light emitting diode is grounded;
in the input port of the second optical coupler, the cathode of the light emitting diode is connected with the signal output end of the terminal A/terminal B, and the anode of the light emitting diode is grounded.
Further, the signal isolation circuit comprises three paths, each path comprising the first optical coupler and the second optical coupler;
the input ports of the first optical coupler and the second optical coupler of the three paths are respectively connected with TXD, DTR and RTS pins of the terminal A/terminal B, and the output ports are respectively connected with RXD, DSR and CTS pins of the terminal B/terminal A.
Furthermore, the signal isolation circuit also comprises a current-limiting resistor; and the signal output end of the terminal A/terminal B is connected with the input ports of the first optical coupler and the second optical coupler through the current-limiting resistor.
Further, the serial port electricity taking circuit takes electricity from the TXD, the DTR and the RTS of the terminal A/terminal B.
Further, the three pins of TXD, DTR and RTS of the terminal a/terminal B are respectively connected with the anodes of the diode D1, the diode D3 and the diode D5, and the cathodes of the diode D1, the diode D3 and the diode D5 are all connected with the output high level of the serial port power-taking circuit;
the three pins of TXD, DTR and RTS of the terminal A/terminal B are respectively connected with the cathodes of a diode D2, a diode D4 and a diode D6, and the anodes of the diode D2, the diode D4 and the diode D6 are all connected with the output low level of the serial port power-taking circuit;
the output high level and the output low level are further respectively connected with the anode of a capacitor C1 and the cathode of a capacitor C2, and the cathode of the capacitor C1 and the anode of the capacitor C2 are grounded after being connected.
Further, the output high level is connected with the cathode of a diode D7, the anode of the diode D7 is connected with the anode of a capacitor C8 and the cathode of a diode D8, and the anode of the diode D8 is grounded;
the negative electrode of the capacitor C8 is connected with one end of the MOS tube Q1 and one end of the MOS tube Q2;
the other end of the MOS transistor Q1 is grounded, and the other end of the MOS transistor Q2 is connected with the output low level;
the output low level is connected with the cathode of a diode D10, the anode of the diode D10 is connected with the cathode of a capacitor C9 and the anode of a diode D9, and the cathode of the diode D8 is grounded;
the anode of the capacitor C9 is connected with one end of a MOS tube Q3 and one end of a MOS tube Q4;
the other end of the MOS transistor Q3 is grounded, and the other end of the MOS transistor Q4 is connected with the output high level.
Further, the serial port electricity taking circuit also comprises a high-frequency square wave generating circuit; the high-frequency square wave generating circuit generates high-frequency square waves to control the on and off of the MOS tube Q1, the MOS tube Q2, the MOS tube Q3 and the MOS tube Q4 respectively.
The beneficial effect of adopting the further scheme is that: the light emitting diodes of the two optical couplers have the positive electrodes connected with the terminal A/the terminal B and the negative electrodes grounded; the cathode of the other light-emitting diode is connected with the terminal A/terminal B, the anode of the other light-emitting diode is grounded, and the terminal A/terminal B is conducted corresponding to one optical coupler when outputting high and low levels, so that the change of the output end from + V to-V is realized, and a redundant control judgment circuit is not needed; the power supply does not need to supply + V and-V power supplies externally, and the stable + V and-V power supplies are realized by directly taking electricity from TXD, DTR and RTS of serial ports; get the electric circuit to ordinary can have data transmission a large amount of data and the baud rate can make the serial ports get the electric voltage unstable than higher, especially under the RS232 signal three-wire system condition, the utility model discloses an increase + V and-V high frequency charge, can guarantee that the voltage of output is all relatively more stable at any time.
Drawings
Fig. 1 is a block diagram of an RS232 signal isolation passive converter according to the present invention;
fig. 2 is a schematic circuit diagram of one path in a signal isolation circuit provided by the present invention;
fig. 3 is the utility model provides a pair of serial ports gets circuit schematic diagram of electric circuit.
Detailed Description
The principles and features of the present invention are described below in conjunction with the following drawings, the examples given are only intended to illustrate the present invention and are not intended to limit the scope of the present invention.
Fig. 1 shows a block diagram of a RS232 signal isolation passive converter according to the present invention, and as can be seen from fig. 1, the converter includes: the serial port power-taking circuit and the signal isolation circuit are connected between the RS232 input and output terminal A and the RS232 input and output terminal B; the number of the serial port electricity-taking circuits and the number of the signal isolation circuits are two, and the data output end of the terminal A is connected with the data input end of the terminal B through the first serial port electricity-taking circuit and the first signal isolation circuit; and the data output end of the terminal B is connected with the data input end of the terminal A through a second serial port electricity-taking circuit and a second signal isolation circuit.
The first serial port electricity-taking circuit and the second serial port electricity-taking circuit respectively take electricity from the signal output port of the terminal A/terminal B and then supply power to the corresponding first signal isolation circuit or second signal isolation circuit.
As shown in fig. 2, the signal isolation circuit according to the present invention includes a first optical coupler and a second optical coupler, and input ports of the first optical coupler and the second optical coupler are connected to a signal output terminal of a terminal a/a terminal B, as can be seen from fig. 2; one pin of the output ports of the first and second optocouplers is connected to a high level or a low level, and the other pin is connected to the signal input port of the terminal B/the terminal a.
In specific implementation, for example, the input ports of the first optical coupler and the second optical coupler are both connected to the signal output port of the terminal a, one end of the output port of the first optical coupler is connected to a high level, one end of the output port of the second optical coupler is connected to a low level, one end of the output port of the first optical coupler is connected to a high level, and the other end of the output port is connected to the signal input port of the terminal B, when the signal output port of the terminal a outputs a high level, the first optical coupler is driven to conduct two pins of the output port of the first optical coupler, and at this time, the signal input port of the terminal B is connected to a high level; when the signal output port of the terminal a outputs a low level, the second optocoupler is driven to conduct the two pins of the output port thereof, and at this time, the signal input port of the terminal B is connected to the low level. Two opto-couplers realize signal isolation respectively and realize that RS232 signal level superposes about 15V again simultaneously, make product cost reduction, product size reduce.
Example 1
The utility model provides an embodiment 1 does the utility model provides a pair of the embodiment of passive converter is kept apart to RS232 signal, do if fig. 3 the utility model provides a pair of serial ports get circuit schematic diagram of electric circuit combines fig. 1, fig. 2 and fig. 3 to know, and the embodiment of this converter includes: and the serial port power-taking circuit and the signal isolation circuit are connected between the RS232 input/output terminal A and the RS232 input/output terminal B.
The number of the serial port electricity-taking circuits and the number of the signal isolation circuits are two, and the first serial port electricity-taking circuit and the second serial port electricity-taking circuit respectively take electricity from the signal output port of the terminal A or the signal output port of the terminal B and then supply power to the corresponding first signal isolation circuit or the corresponding second signal isolation circuit.
The signal isolation circuit comprises a first optical coupler and a second optical coupler, and input ports of the first optical coupler and the second optical coupler are connected with a signal output end of a terminal A/a terminal B; one pin of the output ports of the first and second optocouplers is connected to a high level or a low level, and the other pin is connected to the signal input port of the terminal B/the terminal a.
Preferably, in the input port of the first optocoupler, the anode of the light emitting diode is connected to the signal output terminal of the terminal a/terminal B, and the cathode of the light emitting diode is grounded.
In the input port of the second optocoupler, the cathode of the light emitting diode is connected with the signal output end of the terminal A/terminal B, and the anode of the light emitting diode is grounded.
Specifically, the signal isolation circuit comprises three paths, and each path comprises a first optical coupler and a second optical coupler.
The input ports of the first optical coupler and the second optical coupler of the three paths are respectively connected with TXD, DTR and RTS pins of a terminal A/a terminal B, and the output ports are respectively connected with RXD, DSR and CTS pins of the terminal B/the terminal A. Level isolation transitions between TXD1 to RXD2, DTR to DSR, and RTS to CTS are achieved.
Preferably, the signal isolation circuit further comprises a current limiting resistor R1; the signal output end of the terminal A/terminal B is connected with the input ports of the first optical coupler and the second optical coupler through a current-limiting resistor.
As shown in fig. 2, an embodiment of level-isolated conversion from TXD1 to RXD2 is shown, and in the specific implementation of the embodiment shown in fig. 2, when TXD1 is at a high level, the optocoupler U9 is driven through the current-limiting resistor R1, so that the 3 pins and 4 pins of U9 are turned on, and RXD2 is at a high level + V2; when the TXD1 is in a low level, the current limiting resistor R1 drives the optocoupler U4 to enable the 3 pin and the 4 pin of the U4 to be conducted, so that the RXD2 is in a low level-V2; therefore, the RXD2 signal is changed from + V2 to-V2, and the RS232 standard level requirement is met. The same principle can realize level isolation conversion from DTR to DSR and level isolation conversion from RTS to CTS.
As can be seen from FIG. 3, the serial port power-taking circuit takes power from the TXD, DTR and RTS pins of the terminal A/terminal B.
The power supply does not need to supply + V and-V power supplies externally, and stable + V and-V power supplies are realized by directly taking electricity from TXD, DTR and RTS of serial ports.
Specifically, the TXD, DTR and RTS pins of the terminal a/terminal B are respectively connected to the anodes of the diode D1, the diode D3 and the diode D5, and the cathodes of the diode D1, the diode D3 and the diode D5 are all connected to the output high level + V1 of the serial power circuit.
The TXD, DTR and RTS pins of the terminal A/terminal B are respectively connected with the cathodes of the diode D2, the diode D4 and the diode D6, and the anodes of the diode D2, the diode D4 and the diode D6 are respectively connected with the output low level-V1 of the serial port power-taking circuit.
The output high level and the output low level are respectively connected with the anode of the capacitor C1 and the cathode of the capacitor C2, and the cathode of the capacitor C1 and the anode of the capacitor C2 are grounded after being connected.
The RS232 signal level is two levels between plus (5-15) V or minus (5-15) V, taking TXD1 as an example, when the TXD1 signal is positive, the diode D1 is conducted to charge the capacitor C1, and the output high level + V1 is ensured to be high; when TXD1 is at a negative level, D2 turns on to charge C2, ensuring that the output low-V1 is low.
Specifically, the output high level is connected to the cathode of the diode D7, the anode of the diode D7 is connected to the anode of the capacitor C8 and the cathode of the diode D8, and the anode of the diode D8 is grounded.
The cathode of the capacitor C8 is connected to one end of the MOS transistor Q1 and the MOS transistor Q2.
The other end of the MOS transistor Q1 is grounded, and the other end of the MOS transistor Q2 is connected with the output low level-V1.
The output low level is connected to the cathode of the diode D10, the anode of the diode D10 is connected to the cathode of the capacitor C9 and the anode of the diode D9, and the cathode of the diode D8 is grounded.
The positive electrode of the capacitor C9 is connected to one end of the MOS transistor Q3 and the MOS transistor Q4.
The other end of the MOS transistor Q3 is grounded, and the other end of the MOS transistor Q4 is connected with the output high level + V1.
Preferably, the serial port electricity taking circuit further comprises a high-frequency square wave generating circuit; the high-frequency square wave generating circuit generates high-frequency square waves to respectively control the turn-off of the MOS tube Q1, the MOS tube Q2, the MOS tube Q3 and the MOS tube Q4.
In the specific implementation process of the embodiment shown in fig. 3, a high-frequency square wave is generated by U1 to control the switching of MOS transistors Q1 and Q2, Q3 and Q4, Q1 and Q2 cannot be turned on simultaneously, Q3 and Q4 cannot be turned on simultaneously, GND1 is charged through D8, C8, Q2 and-V1 when Q2 is turned on, when Q1 turns on the negative pole of C8 and GND1 is turned on, a voltage difference + V1 exists between C8 due to the charge of a capacitor of C8, so that the positive level of C8 is + V1, and when the level of C8 is higher than the level of + V1, the charge of C1 through D7 ensures that the level of + V1 is relatively stable; the same principle ensures that the-V1 level is stably output.
The above description is only for the preferred embodiment of the present invention, and should not be construed as limiting the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.
Claims (8)
1. An RS232 signal isolation passive converter, the converter comprising: the serial port power-taking circuit and the signal isolation circuit are connected between the RS232 input and output terminal A and the RS232 input and output terminal B;
the number of the serial port electricity-taking circuits and the number of the signal isolation circuits are two, and the first serial port electricity-taking circuit and the second serial port electricity-taking circuit respectively take electricity from the signal output port of the terminal A or the signal output port of the terminal B and then supply power to the corresponding first signal isolation circuit or the corresponding second signal isolation circuit;
the signal isolation circuit comprises a first optical coupler and a second optical coupler, and input ports of the first optical coupler and the second optical coupler are connected with a signal output end of the terminal A/terminal B; one pin of the output ports of the first optical coupler and the second optical coupler is connected with a high level or a low level, and the other pin of the output ports of the first optical coupler and the second optical coupler is connected with the signal input port of the terminal B/the terminal A.
2. The converter according to claim 1, wherein in the input port of the first optocoupler, the anode of the light emitting diode is connected to the signal output terminal of the terminal a/terminal B, and the cathode of the light emitting diode is grounded;
in the input port of the second optical coupler, the cathode of the light emitting diode is connected with the signal output end of the terminal A/terminal B, and the anode of the light emitting diode is grounded.
3. The converter of claim 1, wherein the signal isolation circuit comprises three paths, each path comprising the first and second optocouplers;
the input ports of the first optical coupler and the second optical coupler of the three paths are respectively connected with TXD, DTR and RTS pins of the terminal A/terminal B, and the output ports are respectively connected with RXD, DSR and CTS pins of the terminal B/terminal A.
4. The converter of claim 1, wherein the signal isolation circuit further comprises a current limiting resistor; and the signal output end of the terminal A/terminal B is connected with the input ports of the first optical coupler and the second optical coupler through the current-limiting resistor.
5. The converter according to claim 1, wherein the serial power-taking circuit takes power from the three pins TXD, DTR and RTS of the terminal a/terminal B.
6. The converter according to claim 5, wherein the TXD, DTR and RTS pins of the terminal A/terminal B are respectively connected with the anodes of a diode D1, a diode D3 and a diode D5, and the cathodes of the diode D1, a diode D3 and a diode D5 are all connected with the output high level of the serial port power-taking circuit;
the three pins of TXD, DTR and RTS of the terminal A/terminal B are respectively connected with the cathodes of a diode D2, a diode D4 and a diode D6, and the anodes of the diode D2, the diode D4 and the diode D6 are all connected with the output low level of the serial port power-taking circuit;
the output high level and the output low level are further respectively connected with the anode of a capacitor C1 and the cathode of a capacitor C2, and the cathode of the capacitor C1 and the anode of the capacitor C2 are grounded after being connected.
7. The converter according to claim 6, wherein the high output level is connected to the cathode of a diode D7, the anode of the diode D7 is connected to the anode of a capacitor C8 and the cathode of a diode D8, and the anode of the diode D8 is connected to ground;
the negative electrode of the capacitor C8 is connected with one end of the MOS tube Q1 and one end of the MOS tube Q2;
the other end of the MOS transistor Q1 is grounded, and the other end of the MOS transistor Q2 is connected with the output low level;
the output low level is connected with the cathode of a diode D10, the anode of the diode D10 is connected with the cathode of a capacitor C9 and the anode of a diode D9, and the cathode of the diode D8 is grounded;
the anode of the capacitor C9 is connected with one end of a MOS tube Q3 and one end of a MOS tube Q4;
the other end of the MOS transistor Q3 is grounded, and the other end of the MOS transistor Q4 is connected with the output high level.
8. The converter according to claim 7, wherein the serial port power-taking circuit further comprises a high-frequency square wave generating circuit; the high-frequency square wave generating circuit generates high-frequency square waves to control the on and off of the MOS tube Q1, the MOS tube Q2, the MOS tube Q3 and the MOS tube Q4 respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022178305.5U CN213367755U (en) | 2020-09-29 | 2020-09-29 | RS232 signal isolation passive converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022178305.5U CN213367755U (en) | 2020-09-29 | 2020-09-29 | RS232 signal isolation passive converter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213367755U true CN213367755U (en) | 2021-06-04 |
Family
ID=76156796
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022178305.5U Active CN213367755U (en) | 2020-09-29 | 2020-09-29 | RS232 signal isolation passive converter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213367755U (en) |
-
2020
- 2020-09-29 CN CN202022178305.5U patent/CN213367755U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109150551B (en) | Non-standard POE power supply circuit, power supply equipment and power supply method for network port | |
| CN104704704A (en) | Charging circuit and terminal | |
| CN203444468U (en) | Communication convertor | |
| CN202111674U (en) | PWM signal driving device | |
| CN206389350U (en) | A kind of light-coupled isolation communicating circuit | |
| CN205430254U (en) | Transmission rate 32Kbps~80Mbps receives and dispatches integrative SFP optical module | |
| CN101174152A (en) | Bus line data transceiver | |
| CN213367755U (en) | RS232 signal isolation passive converter | |
| CN108052041A (en) | Remote on-off control device and system | |
| CN211606512U (en) | Isolation interface circuit based on high-speed optocoupler | |
| CN108923780A (en) | Signal isolation circuit and optical coupler communication circuit with same | |
| CN212518971U (en) | Direct current carrier communication circuit | |
| KR20080083591A (en) | A conversion circuit | |
| CN205071002U (en) | Light module power supply circuit and communications facilities | |
| CN209823751U (en) | System for transmitting data through direct current power line chopping | |
| CN208834145U (en) | CAN bus isolation circuit, power panel and robot | |
| CN108322239B (en) | Close-range unidirectional power supply reverse communication circuit structure | |
| CN107592028B (en) | Inverter circuit system | |
| CN105576641A (en) | CAN-BUS protection circuit and motion control system applying same | |
| CN211089662U (en) | USB changes CAN module with lightning protection | |
| CN104298212A (en) | RS232 and RS485 compatible system | |
| CN207801932U (en) | A kind of isolation RS 485 transmitting-receiving control circuit | |
| CN213402972U (en) | Level conversion circuit and electric equipment | |
| CN212278375U (en) | Novel special host computer of module communication is kept apart to multiple serial ports | |
| CN220087135U (en) | Power supply device and electronic equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |