CN214256720U - Printed circuit board - Google Patents
Printed circuit board Download PDFInfo
- Publication number
- CN214256720U CN214256720U CN202022964101.4U CN202022964101U CN214256720U CN 214256720 U CN214256720 U CN 214256720U CN 202022964101 U CN202022964101 U CN 202022964101U CN 214256720 U CN214256720 U CN 214256720U
- Authority
- CN
- China
- Prior art keywords
- transmission line
- trace
- branch
- circuit board
- printed circuit
- 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
- Dc Digital Transmission (AREA)
- Structure Of Printed Boards (AREA)
Abstract
The embodiment of the utility model provides a printed circuit board is related to, include: the trunk routing comprises a first transmission line and a second transmission line; the first branch line comprises a third transmission line and a fourth transmission line, and one end of the first branch line, which is adjacent to the third transmission line, is electrically connected between the first transmission line and the second transmission line; the signal driving circuit is electrically connected to one end, far away from the second transmission line, of the first transmission line; the first receiving circuit is electrically connected to one end, far away from the third transmission line, of the fourth transmission line; the second receiving circuit is connected to one end, far away from the first transmission line, of the second transmission line; and the first termination resistor is positioned on the first branch wiring and between the third transmission line and the fourth transmission line. The utility model discloses a set up the quantity that termination resistance reduces resistance on the branch line, reduce circuit design cost.
Description
Technical Field
The utility model relates to an electronic hardware designs technical field, especially relates to a printed circuit board.
Background
In a Printed Circuit Board (PCB), signals are transmitted through transmission lines on the PCB, and with the development of technology, people have higher requirements for signal transmission, for example, the signal transmission rate needs to be increased. In the case where one signal driving circuit drives a plurality of loads such as a receiving circuit through a printed circuit board, a plurality of branch lines may appear on a transmission line of a signal, the lengths of the branch lines may differ due to different arrangement positions of the loads of the receiving circuit, and the lengths of the different branch lines have different influences on the integrity of the signal. Since the arrangement positions of the loads on the printed circuit board are different, the branch lengths cannot be controlled according to the will of people due to the limitation of the layout space of the printed circuit board. The signal is affected by the transmission line to generate distortion in the transmission process, and if the signal distortion exceeds the recognizable range of the receiving circuit, the signal transmission generates errors so as to affect the function realization of the product.
In the prior art, by placing pull-up resistors and pull-down resistors on a plurality of receiving circuits, the pull-up resistors need to be connected to a power supply voltage, and the pull-down resistors are grounded. In this way, the reflection of the signal is suppressed so that the signal does not exceed the range recognizable by the receiving circuit.
However, this placement method requires adding a plurality of resistors to the receiving circuit, that is, adding a plurality of resistors to the end of the circuit, which increases the cost of the whole circuit, and adding a plurality of resistors to the end of the circuit causes current to always pass through the plurality of resistors, which increases the power consumption of the whole circuit.
SUMMERY OF THE UTILITY MODEL
Therefore, in order to overcome some of the drawbacks and deficiencies of the prior art, embodiments of the present invention provide a printed circuit board.
On the one hand, the embodiment of the utility model provides a printed circuit board, include: the trunk routing comprises a first transmission line and a second transmission line connected with the first transmission line; a first branch trace, including a third transmission line and a fourth transmission line connected to the third transmission line, wherein one end of the first branch trace adjacent to the third transmission line is electrically connected between the first transmission line and the second transmission line of the trunk trace; the signal driving circuit is electrically connected to one end, far away from the second transmission line, of the first transmission line, wired by the trunk; a first receiving circuit electrically connected to one end of the fourth transmission line far away from the third transmission line on the first branch wiring; the second receiving circuit is connected to one end, far away from the first transmission line, of the second transmission line on the main trunk wiring; and the first termination resistor is positioned on the first branch wiring and between the third transmission line and the fourth transmission line.
In the prior art, because a pull-up resistor and a pull-down resistor need to be arranged on a plurality of receiving terminals, the pull-up resistor needs to be connected to a power supply voltage, the pull-down resistor is grounded, a plurality of resistors need to be used, the circuit design cost is increased, and current needs to flow through the plurality of resistors, so that the power consumption of the system is increased. The embodiment of the utility model provides a set up a termination resistance between third transmission line and the fourth transmission line on the line is walked through the branch at printed circuit board, restrain the influence of the signal reflection on the branch line, reduced the quantity of resistance simultaneously, saved printed circuit board's space, reduced the design cost to and reduced the system power consumption.
In an embodiment of the present invention, the first termination resistor has a resistance value not less than 30 ohms and not more than 50 ohms.
In one embodiment of the present invention, the second transmission line has a length of no greater than 800 mils.
In one embodiment of the present invention, the third transmission line has a length of no greater than 100 mils.
In an embodiment of the present invention, the length of the trunk trace is greater than the length of the branch trace.
In an embodiment of the present invention, the trunk trace is further provided with a second termination resistor and a fifth transmission line, the fifth transmission line is located between the second transmission line and the second receiving circuit, and the second termination resistor is located between the second transmission line and the fifth transmission line.
In an embodiment of the present invention, the resistance value of the second termination resistor is not less than 30 ohms and not more than 50 ohms.
In one embodiment of the present invention, the length of the second transmission line and the third transmission line is no greater than 100 mils.
In an embodiment of the present invention, a sixth transmission line is further disposed on the trunk trace, and the sixth transmission line is located between the second transmission line and the second termination resistor; the printed circuit board further comprises a second branch wiring, the second branch wiring comprises a seventh transmission line, and one end of the second branch wiring is electrically connected between the second transmission line and the fifth transmission line of the main wiring; the printed circuit board further comprises a third receiving circuit electrically connected to the other end of the second branch trace.
In an embodiment of the present invention, the second branch routing further includes: a third termination resistor located on the second branch line and connected between the seventh transmission line and the third receiving circuit; and an eighth transmission line which is located on the second branch wiring and connected between the third termination resistor and the third receiving circuit.
In view of the above, the above technical features of the present invention can have one or more of the following advantages:
1. the embodiment of the utility model provides a through set up the first termination resistance between the third transmission line of branch department and the fourth transmission line of printed circuit board, restrain the signal reflection on the branch line;
2. the utility model arranges a first terminating resistor at the branch, thereby reducing the number of terminating resistors, saving the layout space of the printed circuit board, reducing the design cost and reducing the system power consumption;
3. the utility model discloses a set up a second termination resistance between second transmission line and fifth transmission line to restrain the signal reflection on the trunk line.
4. The utility model discloses a walk to set up termination resistance on line and the second branch walking in first branch for line and the second branch walking of first branch need not shorten length, thereby has reduced the degree of difficulty of printed circuit board overall arrangement.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a printed circuit board according to a first embodiment of the present invention.
Fig. 2 is a schematic structural diagram of a printed circuit board according to a second embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a printed circuit board according to a third embodiment of the present invention.
Fig. 4 is a schematic structural diagram of another printed circuit board according to a third embodiment of the present invention.
Fig. 5 is a comparison diagram of the simulated signal waveform according to the embodiment of the present invention and the simulated signal waveform of the printed circuit board structure in the prior art.
Reference numerals: 10: a printed circuit board; 11: main trunk wiring; 12: a first branch routing; 13: a signal driving circuit; 14: a first receiving circuit; 15: a second receiving circuit; 16: a third receiving circuit; 17: a second branch routing; l1: a first transmission line; l2: a second transmission line; l3: a third transmission line; l4: a fourth transmission line; l5: a fifth transmission line; l6: a sixth transmission line; l7: a seventh transmission line; r1: the first end is connected with a resistor; r2: the second end is connected with a resistor; r3: the third end is connected with a resistor; 21: signal simulation waveforms of prior art printed circuit board structures; 22; the signal of the present embodiment simulates a waveform.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
[ first embodiment ] A method for manufacturing a semiconductor device
As shown in fig. 1, an embodiment of the present invention provides a printed circuit board 10, for example, including: the circuit comprises a main wiring 11, a first branch wiring 12, a signal driving circuit 13, a first receiving circuit 14, a second receiving circuit 15 and a first termination resistor R1.
In this embodiment, the signal driving circuit 13 and the first receiving circuit 14 and the second receiving circuit 15 are connected in a daisy chain topology, and in other embodiments, the signal driving circuit 13 and the first receiving circuit 14 and the second receiving circuit 15 may also be connected in other topologies, which is not limited herein.
The trunk trace 11 is connected to the first branch trace 12 through a connection point, the connection point is located on the trunk trace 11, the signal driving circuit 13 and the second receiving circuit 15 are located on the trunk trace 11, and the signal driving circuit 13 is electrically connected to the second receiving circuit 15; the first termination resistor R1 is located on the first branch line 12, and the first termination resistor R1 is electrically connected to the first receiving circuit 14 and the signal driving circuit 13.
The trunk trace 11 and the first branch trace 12 can be determined according to the length of the trace, where the longest trace from (i.e., the signal driving circuit 13) to the multiple receiving circuits (also called receiving terminals) is the trunk trace, in this embodiment, the trace from the signal driving circuit 13 to the second receiving circuit 15 is the longest trace from the driving terminal to the receiving terminal, i.e., the trace from the signal driving circuit 13 to the second receiving circuit 15 is the trunk trace 11; the first branch trace is a trace led out from the main trace to the receiving end, i.e. a branch trace, and the trace from the signal driving circuit 13 to other receiving ends, e.g. the first receiving circuit 14, is a first branch trace. In other embodiments, the trunk trace 11 may also be determined by other means (for example, automatic determination is performed by an upper computer or a programmable logic device), which is not limited herein.
The trunk trace 11 includes a first transmission line L1 and a second transmission line L2 connected to the first transmission line L1; the first branch trace 12 includes a third transmission line L3 and a fourth transmission line L4 connected to the third transmission line L3, as shown in fig. 1, one end of the first branch trace 12 adjacent to the third transmission line L3 is electrically connected between the first transmission line L1 and the second transmission line L2 of the trunk trace 11 (i.e., the first branch trace 12 is electrically connected to a connection point on the trunk trace 11), and the signal driving circuit 13 is electrically connected to one end of the first transmission line L1 of the trunk trace away from the second transmission line L2; the first receiving circuit 14 is electrically connected to an end of the fourth transmission line L4 away from the third transmission line L3 on the first branch trace 12; the second receiving circuit 15 is connected to an end of the second transmission line L2 away from the first transmission line L1 on the trunk trace 11; the first termination resistor R1 is located on the first branch trace 12 and between the third transmission line L3 and the fourth transmission line L4.
In this embodiment, the signal driving circuit 13 may be a main control chip including an MCU (micro controller Unit; micro control Unit) and an FPGA (Field Programmable Gate Array; Field Programmable Gate Array), where the MCU is, for example, STM32H750XBH6, and the FPGA is, for example, XC7K 160T; in other embodiments, the signal driving circuit 13 may be other chips that transmit signals, and is not limited herein.
In this embodiment, the first receiving circuit 14 and the second receiving circuit 15 are, for example, interface chips such as PHY interface chips for loads on the trunk trace 11 and the first branch trace 12 connected to the signal driving circuit 13; in other embodiments, the first receiving circuit 14 and the second receiving circuit 15 may also be other receiving chips, and are not limited herein.
In this embodiment, the length of the second transmission line L2 is greater than the length of the third transmission line L3, and the difference between the lengths of the second transmission line L2 and the third transmission line L3 is greater than the product of the transmission speed of the driving signal and the rise time of the driving signal of the signal driving circuit, or the sum of the lengths of the third transmission line L3 and the fourth transmission line L4 (i.e., the length of the first branch trace 12) is greater than 1/6 of the product of the transmission speed of the driving signal and the rise time of the driving signal, when any one of the above conditions is satisfied on the printed circuit board, that is, it is proved that the first branch trace 12 on the printed circuit board has an influence on the reflection of the signal, and then the influence of the signal reflection can be suppressed by providing a terminating resistor on the first branch trace 12.
Wherein, the transmission line length of the first branch trace 12 has a certain influence on the signal reflection, which may result in the increase of the parasitic capacitance on the first branch trace 12, because of
Wherein Z is impedance, R is resistance, G is conductivity (also called conductance), L is parasitic inductance, C is parasitic capacitance, which can be obtained from this formula, when parasitic capacitance increases, the impedance can decrease, thereby causing the impedance on the first branch trace 12 to be smaller than the impedance on the trunk trace 11, causing the impedance of the trunk trace 11 and the first branch trace 12 to be mismatched, so that it is necessary to set a terminating resistance on the first branch trace 12, thereby increasing the impedance of the first branch trace 12, causing the impedance of the trunk trace 11 and the first branch trace 12 to be capable of being matched, and reducing the influence of signal reflection.
The first termination resistor R1 is disposed on the first branch trace 12, for dividing the transmission line on the first branch trace 12 into a plurality of transmission lines, for example, in this embodiment, the first branch trace 12 is divided into a third transmission line L3 and a fourth transmission line L4, which reduces the length of the transmission line on the first branch trace 12 affecting the integrity of signal transmission, and in addition, the first termination resistor R1 is added to compensate the resistance on the first branch trace 12, so that the impedances of the main trace 11 and the first branch trace 12 can be matched.
In the prior art, because a pull-up resistor and a pull-down resistor need to be arranged on a plurality of receiving terminals, the pull-up resistor needs to be connected to a power supply voltage, the pull-down resistor is grounded, a plurality of resistors need to be used, the circuit design cost is increased, and current needs to flow through the plurality of resistors, so that the power consumption of the system is increased. The embodiment of the utility model provides a through set up a termination resistance between third transmission line and the fourth transmission line on printed circuit board's branch line, restrain the signal reflection on the branch line, reduced the quantity of resistance simultaneously, saved printed circuit board's space, reduced the design cost to and reduced the system power consumption.
In order to ensure that the main trunk line 11 can have normal efficacy, that is, the second receiving circuit 15 can receive signals with a certain strength, in the embodiment of the present invention, the length of the second transmission line L2 is not greater than 800 mils; that is, the length of the second transmission line L2 is at most 800 mils, and the length of the second transmission line L2 is no greater than 800 mils, the impedance of the main line 11 is not affected by the transmission lines of the main line 11, and thus the integrity of the signal transmission is not affected.
The third transmission line L3 is located on the first branch trace 12, the length of the third transmission line L3 is not greater than 100 mils, i.e., the first terminating resistor R1 can be closer to the connection point of the main trace 11, and when the first terminating resistor R1 is closer to the connection point of the main trace 11, the better the signal reflection effect of the first terminating resistor R1 on the first branch trace 12 is. The reason why the length of the third transmission line L3 is not greater than 100 mils is that the impedance value of the third transmission line L3 is not matched with the impedance value of the first termination resistor R1 after the length of the third transmission line L3 exceeds 100 mils, so that the length of the third transmission line L3 is not greater than 100 mils, and the impedance value of the third transmission line L3 is matched with the impedance value of the first termination resistor R1, so that the transmission integrity of signals is not affected.
The resistance of the first termination resistor R1 may be determined, for example, according to a signal simulation effect performed on the first receiving circuit 14, or the resistance may be determined according to debug of a sample, which is not limited herein. The first terminating resistor R1 has a resistance value of not less than 30 ohms and not more than 50 ohms.
The embodiment of the utility model provides an in printed circuit board's circuit principle as follows: firstly, the main trace 11 and the first branch trace 12 in the pcb are determined, as shown in fig. 1, the driving signal starts from the signal driving circuit 13 and reaches the second receiving circuit 15 and the first receiving circuit 14 respectively along the first transmission line L1 and the second transmission line L2 of the main trace 11 and the third transmission line L3 and the fourth transmission line L4 of the first branch trace 12.
Then, it is determined whether the difference between the transmission line length on the first branch trace 12 and the transmission line length on the trunk trace 11 is greater than the product of the transmission speed of the driving signal sent by the signal driving circuit 13 and the signal rising time, for example, the difference between the length of the second transmission line L2 and the length of the third transmission line L3 is greater than the product of the transmission speed of the signal driving circuit and the signal rising time. Or determining 1/6 whether the length of the first branch trace is greater than the product of the driving signal transmission speed and the signal rise time, for example, whether the sum of the third transmission line L3 and the fourth transmission line L4 is greater than 1/6 of the product of the driving signal transmission speed and the signal rise time, and only when either of these two conditions is satisfied, it is proved that the length of the first branch trace 12 has an influence on signal reflection, and then it is necessary to provide a terminating resistor on the first branch trace 12. Then, the position of the termination resistor is determined, and the closer the position of the termination resistor disposed on the first branch line is to the connection point of the main line 11, the better the effect of suppressing signal reflection, but due to the layout of the actual printed circuit board, the termination resistor cannot be placed at the connection point of the main line 11, so the first termination resistor R1 in this embodiment is placed between the third transmission line L3 and the fourth transmission line L4 of the first branch line 12.
The first terminating resistor R1 on the first branch trace 12 is used to match the impedance of the output resistor of the signal driving circuit 13 and the transmission line on the branch line, and the resistance value of the first terminating resistor R1 can be determined by simulation software.
Confirm first termination resistance R1's resistance, place the position to and after the topological structure, then carry out the contrast of signal emulation wave form to this printed circuit board, as shown in fig. 5, can see from fig. 5 the utility model discloses a simulation wave form that the scheme obtained compares with the emulation ripples star that prior art obtained, the utility model discloses an emulation wave form's border is more level and smooth to the complete transmission of assurance signal that can be better suppresses the reflection of signal.
[ second embodiment ]
As shown in fig. 2, in the embodiment of the present invention, the printed circuit board 20 includes: the circuit comprises a main wiring 11, a first branch wiring 12, a signal driving circuit 13, a first receiving circuit 14, a second receiving circuit 15, a first terminating resistor R1 and a second terminating resistor R2. The first branch trace 12, the signal driving circuit 13, the first receiving circuit 14, the second receiving circuit 15, and the first terminating resistor R1 are similar to those in the first embodiment, and detailed description thereof is omitted here.
The trunk trace 11 further includes a second termination resistor R2 and a fifth transmission line L5; the fifth transmission line L5 is located between the second transmission line L2 and the second receiving circuit 15, and the second terminating resistor R2 is located between the second transmission line L2 and the fifth transmission line L5. By providing a terminating resistor on the trunk trace 11, signal reflection by the second receiving circuit 15 is suppressed.
The lengths of the second transmission line L2 and the third transmission line L3 are not more than 100 mils, so that the first terminating resistor R1 and the second terminating resistor R2 are both closer to a connection point, and a better signal reflection inhibition effect is achieved. Since the length of the second transmission line L2 is not greater than 100 mils, which results in the impedance value of the second transmission line L2 not matching the impedance value of the second terminating resistor R2, it is necessary to set the length of the second transmission line L2 to be not greater than 100 mils, so that the impedance value of the second transmission line L2 matches the impedance value of the second terminating resistor R2, and the transmission integrity of signals is not affected.
The resistance of the second termination resistor R2 may be determined according to a signal simulation effect performed on the second receiving circuit 15, or the resistance thereof may be determined according to debug of a sample, which is not limited herein. And the second terminating resistor R2 has a resistance value of not less than 30 ohms and not more than 50 ohms.
The circuit principle of the printed circuit board 20 shown in fig. 2 is similar to that of the printed circuit board 10 described in the foregoing first embodiment, and detailed description thereof is omitted here.
[ third embodiment ]
As shown in fig. 3, an embodiment of the present invention provides a printed circuit board 50, for example, including: the antenna comprises a main wiring 11, a first branch wiring 12, a second branch wiring 17, a signal driving circuit 13, a first receiving circuit 14, a second receiving circuit 15, a third receiving circuit 16, a first terminating resistor R1 and a second terminating resistor R2. The main trace 11, the first branch trace 12, the signal driving circuit 13, the first receiving circuit 14, the second receiving circuit 15, the first terminating resistor R1, and the second terminating resistor R2 are similar to those provided in the second embodiment, and detailed description thereof is omitted here.
A sixth transmission line L6 is further disposed on the trunk trace 11, and the sixth transmission line L6 is located between the second transmission line L2 and the second terminating resistor R2.
The second branch trace 17 includes a seventh transmission line L7, and one end of the second branch trace 17 is electrically connected between the second transmission line L2 and the fifth transmission line L5 of the trunk trace 11 (i.e., the second branch trace 17 is connected to the trunk trace 11 and intersects at a connection point B, and the connection point B is located between the second transmission line L2 and the fifth transmission line L5).
Wherein the printed circuit board further includes a third receiving circuit electrically connected to the other end of the second branch trace 17. The second branch trace 17 does not need to be provided with a terminating resistor, which proves that the length of the seventh transmission line of the second branch trace 17 has no influence on signal reflection
Further, as shown in fig. 4, an embodiment of the present invention provides a printed circuit board 50, wherein the second branch trace 17 further includes:
a third connecting resistor R3 located on the second branch line 17 and connected between the seventh transmission line L7 and the third receiving circuit 16;
an eighth transmission line L8 is located on the second branch line 17 and connected between the third termination resistor R3 and the third receiving circuit 16.
The condition that the third termination resistor R3 is disposed on the second branch trace is that the length of the fifth transmission line L5 is greater than the length of the seventh transmission line L7, and the difference between the lengths of the fifth transmission line L5 and the seventh transmission line L7 is greater than the product of the transmission speed of the driving signal and the rise time of the driving signal of the signal driving circuit, or the sum of the lengths of the seventh transmission line L7 and the eighth transmission line L8 (i.e., the length of the second branch trace 17) is greater than 1/6 of the product of the transmission speed of the driving signal and the rise time of the driving signal.
When the second branch trace 17 on the printed circuit board 50 does not satisfy the above condition, it indicates that the transmission line length of the second branch trace 17 has no influence on signal reflection, so when the second branch trace 17 does not satisfy the above condition, the second branch trace 17 does not need to be provided with a termination resistor.
The length of the seventh transmission line L7 is not more than 100 mils, so that the third connecting resistor R3 is closer to the connecting point B, and the signal reflection inhibiting effect is better.
The resistance of the third terminating resistor R3 is also determined as the first terminating resistor R1 in the first embodiment or as the second terminating resistor R2 in the second embodiment.
In the present embodiment, a circuit on two branch traces is taken as an example for explanation, in other embodiments, when a printed circuit board includes a plurality of branch traces, each branch trace encountered may determine whether the branch trace affects signal reflection according to the method described in the first embodiment, and if the branch trace affects signal reflection, it is necessary to place a termination resistor and determine a position where the termination resistor is placed to suppress the influence on signal reflection in the branch trace; if there is no influence, the termination resistor does not need to be placed, and details are not described here.
To sum up, the embodiment of the present invention first determines whether the branch trace affects signal reflection, and when determining that the branch trace affects signal reflection, a terminating resistor is disposed between transmission lines on the branch trace of the printed circuit board to suppress signal reflection on the branch line, and meanwhile, the number of the terminating resistors is reduced, thereby saving layout space of the printed circuit board, reducing design cost and reducing system power consumption; the utility model discloses still through set up a termination resistance between the transmission line on the main line to restrain the signal reflection on the main line, make the transmission of signal more complete.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.
Claims (10)
1. A printed circuit board, comprising:
a trunk trace (11) comprising a first transmission line (L1) and a second transmission line (L2) connecting the first transmission line (L1);
a first branch trace (12) comprising a third transmission line (L3) and a fourth transmission line (L4) connecting the third transmission line (L3), one end of the first branch trace (12) adjacent to the third transmission line (L3) being electrically connected between the first transmission line (L1) and the second transmission line (L2) of the trunk trace (11);
a signal driving circuit (13) electrically connected to one end of the first transmission line (L1) far away from the second transmission line (L2) of the trunk trace (11);
a first receiving circuit (14) electrically connected to an end of the fourth transmission line (L4) far away from the third transmission line (L3) on the first branch trace (12);
a second receiving circuit (15) connected to an end of the second transmission line (L2) on the trunk trace (11) away from the first transmission line (L1);
a first termination resistor (R1) located on the first branch trace (12) and between the third transmission line (L3) and the fourth transmission line (L4).
2. The printed circuit board according to claim 1, wherein the first termination resistance (R1) has a resistance value of not less than 30 ohms and not more than 50 ohms.
3. The printed circuit board of claim 1, wherein the length of the second transmission line (L2) is no greater than 800 mils.
4. The printed circuit board of claim 1, wherein the third transmission line (L3) has a length of no more than 100 mils.
5. The printed circuit board according to claim 1, wherein the trunk trace (11) has a length greater than the branch trace (12).
6. The pcb of claim 1, wherein a second terminating resistor (R2) and a fifth transmission line (L5) are further disposed on the trunk trace (11), the fifth transmission line (L5) is located between the second transmission line (L2) and the second receiving circuit (15), and the second terminating resistor (R2) is located between the second transmission line (L2) and the fifth transmission line (L5).
7. A printed circuit board according to claim 6, wherein the second terminating resistance (R2) has a resistance value of not less than 30 ohms and not more than 50 ohms.
8. The printed circuit board of claim 7, wherein the second transmission line (L2) and the third transmission line (L3) have a length of no greater than 100 mils.
9. The printed circuit board of claim 6, wherein a sixth transmission line (L6) is further disposed on the trunk trace (11), the sixth transmission line (L6) is located between the second transmission line (L2) and the second terminating resistor (R2);
the printed circuit board (10) further comprises a second branch trace (17), the second branch trace (17) comprises a seventh transmission line (L7), and one end of the second branch trace (17) is electrically connected between the second transmission line (L2) and the fifth transmission line (L5) of the main trace (11);
the printed circuit board (10) further comprises a third receiving circuit (16) electrically connected to the other end of the second branch trace (17).
10. A printed circuit board according to claim 9, characterized in that the second branch trace (17) further comprises:
a third terminating resistor (R3) located on the second branch trace (17) and connected between the seventh transmission line (L7) and the third receiving circuit (16);
an eighth transmission line (L8) located on the second branch trace (17) and connected between the third termination resistor (R3) and the third receiving circuit (16).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022964101.4U CN214256720U (en) | 2020-12-12 | 2020-12-12 | Printed circuit board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022964101.4U CN214256720U (en) | 2020-12-12 | 2020-12-12 | Printed circuit board |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214256720U true CN214256720U (en) | 2021-09-21 |
Family
ID=77737578
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022964101.4U Active CN214256720U (en) | 2020-12-12 | 2020-12-12 | Printed circuit board |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214256720U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115442176A (en) * | 2022-08-22 | 2022-12-06 | 中国电子科技集团公司第十四研究所 | Large-scale multi-load single-ended bus circuit |
-
2020
- 2020-12-12 CN CN202022964101.4U patent/CN214256720U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115442176A (en) * | 2022-08-22 | 2022-12-06 | 中国电子科技集团公司第十四研究所 | Large-scale multi-load single-ended bus circuit |
| CN115442176B (en) * | 2022-08-22 | 2024-04-16 | 中国电子科技集团公司第十四研究所 | Large-scale multi-load single-ended bus circuit |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1214785B1 (en) | A system and method for analyzing simultaneous switching noise | |
| KR970009693B1 (en) | Signal transmitting device circuit block and integrated circuit suited to fast signal transmission | |
| KR100689967B1 (en) | Memory system with improved multi-module memory bus using wilkinson power divider | |
| US9515031B2 (en) | Mitigation of far-end crosstalk induced by routing and out-of-plane interconnects | |
| CN103460200B (en) | For the socket designs of flexible easily extensible system architecture | |
| CN214256720U (en) | Printed circuit board | |
| US6161215A (en) | Package routing of integrated circuit signals | |
| CN103294423A (en) | Chip comprising signal transmission circuit, inter-chip communication system and configuration method of inter-chip communication system | |
| CN101102641A (en) | Printed circuit board | |
| US6067596A (en) | Flexible placement of GTL end points using double termination points | |
| CN214315734U (en) | PCB structure for optimizing multi-load daisy chain topology branch impedance | |
| CN100518436C (en) | Cabling configuration for transmission line in high-speed printed circuit board | |
| Anish et al. | Minimization of crosstalk in high speed PCB | |
| CN209982807U (en) | PCB structure for optimizing signal quality of T topology DDR module | |
| CN101187950A (en) | Multi-load topology cabling architecture | |
| CN210042356U (en) | DDR module signal quality's of optimizing daisy chain topology PCB structure | |
| CN102958268A (en) | Printed circuit board | |
| US20160211844A1 (en) | Impedance matching for high speed signaling in memory system | |
| CN111225489B (en) | Power transmission circuit and electronic equipment | |
| CN220292254U (en) | PCIE golden finger structure for improving impedance | |
| US20030221863A1 (en) | Data bus with separate matched line impedances and method of matching line impedances | |
| CN211019411U (en) | PCB structure for optimizing multi-load topological signal quality | |
| CN110839314B (en) | PCB board | |
| US20080162801A1 (en) | Series termination for a low power memory interface | |
| CN114302554B (en) | PCB (printed circuit board) capable of improving integrity of cross-split signals based on capacitance and layout method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |