CN113316381A - Printed circuit mother board and printed circuit board assembly - Google Patents
Printed circuit mother board and printed circuit board assembly Download PDFInfo
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- CN113316381A CN113316381A CN202110444276.9A CN202110444276A CN113316381A CN 113316381 A CN113316381 A CN 113316381A CN 202110444276 A CN202110444276 A CN 202110444276A CN 113316381 A CN113316381 A CN 113316381A
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- motherboard
- field effect
- effect transistor
- connectors
- printed wiring
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- 230000005669 field effect Effects 0.000 claims abstract description 54
- 238000001514 detection method Methods 0.000 claims description 16
- 230000009977 dual effect Effects 0.000 claims description 3
- 238000009434 installation Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 5
- 238000013461 design Methods 0.000 description 3
- 238000012790 confirmation Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000014509 gene expression Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
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Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K13/00—Apparatus or processes specially adapted for manufacturing or adjusting assemblages of electric components
- H05K13/04—Mounting of components, e.g. of leadless components
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
- H01R43/00—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors
- H01R43/26—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors for engaging or disengaging the two parts of a coupling device
Abstract
The invention discloses a printed circuit motherboard and a printed circuit board assembly, the printed circuit motherboard comprises: a first field effect transistor with a grounded source electrode; the grid electrode of the second field effect transistor is connected in series to the drain electrode of the first field effect transistor; a motherboard connector disposed on the motherboard and connected to the gate of the first field effect transistor; a light emitting diode, the cathode of which is connected to the drain electrode of the second field effect transistor; and one ends of the voltage dividing resistors are respectively connected to the grid electrode of the first field effect transistor, the drain electrode of the first field effect transistor and the anode of the light emitting diode, and the other ends of the voltage dividing resistors are respectively connected to a positive voltage source. The invention can conveniently confirm whether the printed circuit board is assembled in place, and improves the installation quality and the product stability.
Description
Technical Field
The present invention relates to the field of assembly, and more particularly, to a printed circuit motherboard and a printed circuit board assembly.
Background
As the era progresses, the architecture of servers is becoming more complex and larger. Different cables are often used in server architecture configurations to keep flexible cables in wide use, making the system more difficult to manufacture and assemble and less easy to maintain at a later date.
The server is assembled by a plurality of boards (a mother board, a middle board, a side board, a back board and the like). Due to the large combination range of the motherboard and the middle board, the assembly may be incomplete (such as access is not in place, contact is poor, etc.), and the motherboard cannot work normally or even is burnt out after being powered on. In order to avoid assembly errors, the prior art uses positioning pins or structural members beside the linker to ensure that the assembly is in place, but when one board has more than one linker, or the linker is not located at the outermost sides of the board, it is not possible to ensure that the two boards are perfectly combined.
Aiming at the problem that the printed circuit board in the prior art is difficult to confirm whether to be assembled in place, no effective solution is available at present.
Disclosure of Invention
In view of the above, an object of the embodiments of the present invention is to provide a printed circuit motherboard and a printed circuit board assembly, which can facilitate to determine whether the printed circuit board is assembled in place, and improve the mounting quality and the product stability.
In view of the above object, a first aspect of embodiments of the present invention provides a printed wiring motherboard including a mounting detection circuit, and the mounting detection circuit includes:
a first field effect transistor with a grounded source electrode;
the grid electrode of the second field effect transistor is connected in series to the drain electrode of the first field effect transistor;
a motherboard connector disposed on the motherboard and connected to the gate of the first field effect transistor;
a light emitting diode, the cathode of which is connected to the drain electrode of the second field effect transistor;
and one ends of the voltage dividing resistors are respectively connected to the grid electrode of the first field effect transistor, the drain electrode of the first field effect transistor and the anode of the light emitting diode, and the other ends of the voltage dividing resistors are respectively connected to a positive voltage source.
In some embodiments, the motherboard connector is configured to feed back a low level as a daughter board on-site signal in a state of being coupled to the daughter board and turning on the daughter board loop, and to turn off the first fet, turn on the second fet, and turn on the light emitting diode.
In some embodiments, the motherboard connector is configured to feed back a high level as a daughter board on-site signal in a state of not being coupled to the daughter board or being coupled to the daughter board but not turning on the daughter board loop, and to turn on the first fet, turn off the second fet, and turn off the light emitting diode.
In some embodiments, the positive voltage source is connected to a positive pole of a system power supply located outside the motherboard, and a negative pole of the system power supply is grounded.
In some embodiments, a button cell is also included; the positive voltage source is connected to the positive pole of the button cell on the motherboard, and the negative pole of the button cell is grounded.
In some embodiments, a dual power supply connector is further included; the button cell is connected with the positive voltage source and the ground through the double-circuit power supply connector.
In some embodiments, the assembly detection circuits are in multiple groups; the motherboard connectors of each set of assembly detection circuits may all be mated to different connectors of the same daughter board, connectors of different daughter boards, or not.
In some embodiments, the plurality of motherboard connectors each have a different physical fool-proofing structure from one another.
In some embodiments, a plurality of motherboard connectors are joined to connectors having different impedances from one another; the plurality of sets of fitting detection circuits confirm whether the connection is correct based on the impedance of the joined connectors.
A second aspect of an embodiment of the present invention provides a printed wiring board assembly including:
the aforementioned printed wiring motherboard;
one or more printed circuit daughter boards, each printed circuit daughter board comprising one or more daughter board connectors connected to ground, each daughter board connector connected to a corresponding mother board connector, wherein the printed circuit daughter board comprises at least one of: middle plate, curb plate, backplate.
The invention has the following beneficial technical effects: according to the printed circuit motherboard and the printed circuit board assembly provided by the embodiment of the invention, the first field effect transistor with the grounded source electrode is used; the grid electrode of the second field effect transistor is connected in series to the drain electrode of the first field effect transistor; a motherboard connector disposed on the motherboard and connected to the gate of the first field effect transistor; a light emitting diode, the cathode of which is connected to the drain electrode of the second field effect transistor; one end of each divider resistor is connected to the grid of the first field effect transistor, the drain of the first field effect transistor and the anode of the light emitting diode respectively, and the other end of each divider resistor is connected to the positive voltage source.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic circuit diagram of a printed circuit motherboard according to the present invention;
FIG. 2 is a schematic circuit diagram of the power supply side of a printed wiring motherboard provided by the present invention;
FIG. 3 is a schematic structural diagram of a plurality of sets of assembly detection circuits of a printed circuit motherboard according to the present invention;
fig. 4 is a schematic circuit diagram of a printed wiring board assembly provided by the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the following embodiments of the present invention are described in further detail with reference to the accompanying drawings.
It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are used for distinguishing two entities with the same name but different names or different parameters, and it should be noted that "first" and "second" are merely for convenience of description and should not be construed as limitations of the embodiments of the present invention, and they are not described in any more detail in the following embodiments.
In view of the above, a first aspect of the embodiments of the present invention provides an embodiment of a printed circuit motherboard that facilitates confirmation of whether a printed circuit board is assembled in place, and improves mounting quality and product stability. Fig. 1 shows a schematic circuit diagram of a printed circuit motherboard according to the invention.
The printed wiring motherboard includes a mounting detection circuit, and the mounting detection circuit includes, as shown in fig. 1:
a first field effect transistor Q1 with its source grounded;
a second field effect transistor Q2 with a grounded source and a grid connected in series to the drain of the first field effect transistor Q1;
a motherboard connector disposed on the motherboard and connected to the gate of the first field effect transistor Q1;
a light emitting diode LED having a cathode connected to the drain of the second field effect transistor Q2;
one ends of the voltage dividing resistors R1, R2 and R3 are respectively connected to the gate of the first field-effect transistor Q1, the drain of the first field-effect transistor Q1 and the anode of the light-emitting diode LED, and the other ends are connected to the positive voltage source + VCC.
In some embodiments, the motherboard connector is configured to feed back a low level as a daughter board on-bit signal in a state of being coupled to the daughter board and turning on the daughter board loop, and to turn off the first fet Q1, and turn on the fet Q2, and the LED emits light.
In some embodiments, the motherboard connector is configured to feed back a high level as a daughter board on-bit signal in a state of not being coupled to the daughter board or being coupled to the daughter board but not turning on the daughter board loop, and to turn on the first fet Q1, and turn off the fet Q2, the light emitting diode LED does not emit light.
In some embodiments, the positive voltage source + VCC is connected to the positive pole of a system power supply located off the motherboard, and the negative pole of the system power supply is grounded.
In some embodiments, a button cell is also included; the positive voltage source + VCC is connected to the positive pole of the coin cell on the motherboard and the negative pole of the coin cell is grounded.
In some embodiments, a dual power supply connector is further included; the button cell is connected with a positive voltage source + VCC and the ground through a double-circuit power supply connector.
In some embodiments, the assembly detection circuits are in multiple groups; the motherboard connectors of each set of assembly detection circuits may all be mated to different connectors of the same daughter board, connectors of different daughter boards, or not.
In some embodiments, the plurality of motherboard connectors each have a different physical fool-proofing structure from one another.
In some embodiments, a plurality of motherboard connectors are joined to connectors having different impedances from one another; the plurality of sets of fitting detection circuits confirm whether the connection is correct based on the impedance of the joined connectors.
The following further illustrates embodiments of the invention in accordance with the specific example shown in fig. 2.
In a circuit, one of the methods of determining the current flowing through a load is to use a mosfet for current sensing. Conventional current sense power mosfets typically include thousands of transistor cells connected in parallel, sharing common drain, source and gate electrodes. Each transistor cell or element within the device is identical and the current at the drain terminal of the device is identical between them. It is common in such designs that the source electrodes of some of the transistors are connected to a separate source terminal, separate from the remaining source electrodes. Thus, the resulting current sensing MOS fet can be viewed as equivalent to two or more transistors in parallel, having common gate and drain terminals, and a separate source terminal. The first of these transistors, which contains most of the transistor cells in the current sensing power mosfet, is commonly referred to as the main fet. The second part, which contains a plurality of transistor cells with discrete source terminals, is called the sense fet.
In use, the sense fet conducts only a small fraction of the current on the common drain terminal, which is inversely proportional to the sense ratio n, where n is the current ratio, which depends on the ratio of the number of transistor cells in the main fet to the number of transistor cells in the sense fet. The sensing ratio n is defined in order to keep the source terminals of the sensing fet and the main fet conducting at the same potential. When the sense ratio is known, the total current flowing through the device, and thus the load current on the load to which the device is connected, can be calculated by measuring the source current on the sense fet (i.e., the current flowing through the current path of the sense fet between the drain and source electrodes).
In a field effect transistor, Gate Induced Drain Leakage (GIDL) current has a large impact on the reliability of the field effect transistor. Leakage currents causing static power consumption in field effect transistors are mainly: source-to-drain subthreshold leakage current, gate-induced drain leakage GIDL current occurring at the gate-to-drain overlap region. Of these leakage currents, GIDL current dominates the leakage current when the device in the circuit is in an off state or in a standby state. As the gate oxide layer gets thinner and thinner, GIDL current increases sharply. With the rapid development of very large scale integrated circuit technology, the size of the field effect transistor is continuously decreasing. Due to the drastic reduction in the size of field effect transistors, the thickness of the gate oxide layer is reduced to 2nm or even thinner. As devices are scaled down in size, the operating voltage is not correspondingly scaled down, which results in a significant increase in the channel and oxide electric fields of the device.
The present invention uses the in-place signal of each connector on the middle plate as a trigger signal, when the in-place signal is correctly connected, the in-place signal of the motherboard is pulled down by the in-place signal of the middle plate, namely, the LED is lighted when the assembly is complete.
The LED can be selected to leave a head connected with a button battery (such as CR2032) for power supply, so as to be used for inspection by assembly personnel. When the desk is directly powered by the power supply, the power of the LED is converted to system power rather than passing through the button cell. The button cell can be assembled without connecting to save power, and the button cell can be charged with power supplied from a power supply. The button cell is connected to the power supply connector through the covered wire.
As shown in fig. 2, when the midplane is in place, the connector of the midplane pulls the level to a low level through the connector connected to the motherboard, the low level turns Q1 off Q2 to conduct, and lights the LED to inform the assembler that the midplane is properly assembled. Otherwise, if the assembly is not complete, the low level (ground) cannot be transmitted to the logic circuit to enable the logic circuit to be continuously at the high level, the Q1 is turned on, the Q2 is turned off, the LED cannot be turned on to emit light, the assembly personnel check again, and the related logic increment table is shown in the following.
| The assembly is perfect | Poor assembly | |
| Logic value of on-bit signal | 0(GND) | 1(VCC) |
| Transistor Q1 state | Off | On |
| Transistor Q2 state | On | Off |
| LED status | Bright Light (LIGHT) | Is not bright |
The above connection is not limited to the middle plate, but may be used for the side plates and the back plate.
In FIG. 3, the in-place signal wiring design through the midplane connects to the logic through the connector, thus requiring a match in board design. When multiple connectors are designed with multiple sets of LEDs for complete protection, the possibility of complete assembly of a single connector and incomplete assembly of the other connectors is eliminated.
As can be seen from the foregoing embodiments, the printed circuit motherboard according to the embodiments of the present invention uses the first field effect transistor with its source grounded; the grid electrode of the second field effect transistor is connected in series to the drain electrode of the first field effect transistor; a motherboard connector disposed on the motherboard and connected to the gate of the first field effect transistor; a light emitting diode, the cathode of which is connected to the drain electrode of the second field effect transistor; one end of each divider resistor is connected to the grid of the first field effect transistor, the drain of the first field effect transistor and the anode of the light emitting diode respectively, and the other end of each divider resistor is connected to the positive voltage source.
In view of the above objects, a second aspect of the embodiments of the present invention provides an embodiment of a printed wiring board assembly that facilitates confirmation of whether a printed wiring board is assembled in place, improving mounting quality and product stability.
A printed wiring board assembly is shown in fig. 4, and includes the aforementioned printed wiring motherboard;
the aforementioned printed wiring motherboard;
one or more printed circuit daughter boards, each printed circuit daughter board comprising one or more daughter board connectors connected to ground, each daughter board connector connected to a corresponding mother board connector, wherein the printed circuit daughter board comprises at least one of: middle plate, curb plate, backplate.
As can be seen from the above embodiments, the printed circuit board assembly provided by the embodiments of the present invention is formed by using the first fet with a grounded source; the grid electrode of the second field effect transistor is connected in series to the drain electrode of the first field effect transistor; a motherboard connector disposed on the motherboard and connected to the gate of the first field effect transistor; a light emitting diode, the cathode of which is connected to the drain electrode of the second field effect transistor; one end of each divider resistor is connected to the grid of the first field effect transistor, the drain of the first field effect transistor and the anode of the light emitting diode respectively, and the other end of each divider resistor is connected to the positive voltage source.
It is to be noted that the above-mentioned embodiment of the printed wiring board assembly employs the embodiment of the printed wiring motherboard to specifically describe the working process of each module, and those skilled in the art can easily think that these modules are applied to other embodiments of the printed wiring motherboard. Of course, since the modules in the embodiment of the printed circuit motherboard can be crossed, replaced, added, or deleted, these reasonable permutations and combinations should also fall within the scope of the present invention, and should not limit the scope of the present invention to the embodiment.
Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, of embodiments of the invention is limited to these examples; within the idea of an embodiment of the invention, also technical features in the above embodiment or in different embodiments may be combined and there are many other variations of the different aspects of an embodiment of the invention as described above, which are not provided in detail for the sake of brevity. Therefore, any omissions, modifications, substitutions, improvements, and the like that may be made without departing from the spirit and principles of the embodiments of the present invention are intended to be included within the scope of the embodiments of the present invention.
Claims (10)
1. A printed wiring motherboard, comprising a mounting detection circuit, and wherein the mounting detection circuit comprises:
a first field effect transistor with a grounded source electrode;
a second field effect transistor with a grounded source electrode, wherein the grid electrode of the second field effect transistor is connected to the drain electrode of the first field effect transistor in series;
the motherboard connector is arranged on the motherboard and is connected to the grid electrode of the first field effect transistor;
a light emitting diode, the cathode of which is connected to the drain electrode of the second field effect transistor;
and one ends of the voltage dividing resistors are respectively connected to the grid electrode of the first field effect transistor, the drain electrode of the first field effect transistor and the anode of the light emitting diode, and the other ends of the voltage dividing resistors are respectively connected to a positive voltage source.
2. A printed wiring motherboard according to claim 1, wherein said motherboard connector is configured to feed back a low level as a daughter board on-position signal in a state of being attached to a daughter board and turning on a daughter board loop, and to turn off said first fet and turn on said second fet, and said light emitting diode emits light.
3. A printed wiring motherboard according to claim 1 wherein said motherboard connector is configured to feed back a high level as a daughter board in-place signal in a state of being not attached to a daughter board, or attached to a daughter board but not conducting a daughter board loop, and to turn on said first fet, turn off said second fet, and turn off said light emitting diode.
4. A printed wiring motherboard according to claim 1 wherein the positive voltage source is connected to the positive pole of a system power supply located off the motherboard and the negative pole of the system power supply is connected to ground.
5. The printed wiring motherboard of claim 1, further comprising a button cell; the positive voltage source is connected to the positive pole of the button cell on the motherboard, and the negative pole of the button cell is grounded.
6. A printed wiring motherboard according to claim 5, further comprising a dual feed connection; the button cell is connected with the positive voltage source and the ground through the two-way power supply connector.
7. The printed wiring motherboard of claim 1, wherein the assembly detection circuits are in a plurality of sets; the motherboard connectors of each set of the assembly detection circuits are all mated to different connectors of the same daughter board, connectors of different daughter boards, or not.
8. A printed wiring motherboard according to claim 7 wherein a plurality of said motherboard connectors each have a different physical fool-proofing structure from one another.
9. A printed wiring motherboard according to claim 7 wherein a plurality of said motherboard connectors are joined to connectors having different impedances from one another; a plurality of sets of the fitting detection circuits confirm whether the connection is correct or not based on the impedance of the joined connectors.
10. A printed wiring board assembly, comprising:
a printed wiring motherboard according to any of claims 1 to 9;
one or more printed circuit daughter boards, each of said printed circuit daughter boards comprising one or more daughter board connectors connected to ground, each of said daughter board connectors being connected to a corresponding one of said motherboard connectors, wherein said printed circuit daughter boards comprise at least one of: middle plate, curb plate, backplate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110444276.9A CN113316381A (en) | 2021-04-23 | 2021-04-23 | Printed circuit mother board and printed circuit board assembly |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110444276.9A CN113316381A (en) | 2021-04-23 | 2021-04-23 | Printed circuit mother board and printed circuit board assembly |
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| CN113316381A true CN113316381A (en) | 2021-08-27 |
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| CN202110444276.9A Pending CN113316381A (en) | 2021-04-23 | 2021-04-23 | Printed circuit mother board and printed circuit board assembly |
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| CN205103947U (en) * | 2015-11-17 | 2016-03-23 | 智慧方舟科技有限公司 | Status indicator lamp control circuit |
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| CN209001578U (en) * | 2018-09-19 | 2019-06-18 | 深圳市智微智能科技开发有限公司 | A kind of anti-inserted anti-short-circuit protection circuit of LVDS interface |
| US20190257874A1 (en) * | 2017-09-21 | 2019-08-22 | Chengdu Boe Optoelectronics Technology Co., Ltd. | Printed circuit board, method for determining engagement state between printed circuit board and flexible printed circuit and display device |
| CN209878946U (en) * | 2019-03-19 | 2019-12-31 | 深圳市智微智能科技开发有限公司 | Mainboard detection circuit |
| CN111596606A (en) * | 2020-04-03 | 2020-08-28 | 福建星云电子股份有限公司 | Fool-proof wiring method for connector |
| CN213027525U (en) * | 2020-07-20 | 2021-04-20 | 深圳市兆驰数码科技股份有限公司 | Power supply switching circuit |
-
2021
- 2021-04-23 CN CN202110444276.9A patent/CN113316381A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN205103947U (en) * | 2015-11-17 | 2016-03-23 | 智慧方舟科技有限公司 | Status indicator lamp control circuit |
| US20190257874A1 (en) * | 2017-09-21 | 2019-08-22 | Chengdu Boe Optoelectronics Technology Co., Ltd. | Printed circuit board, method for determining engagement state between printed circuit board and flexible printed circuit and display device |
| CN209001578U (en) * | 2018-09-19 | 2019-06-18 | 深圳市智微智能科技开发有限公司 | A kind of anti-inserted anti-short-circuit protection circuit of LVDS interface |
| CN109633349A (en) * | 2018-12-11 | 2019-04-16 | 郑州云海信息技术有限公司 | A kind of device of quick detection abnormal voltage position |
| CN209878946U (en) * | 2019-03-19 | 2019-12-31 | 深圳市智微智能科技开发有限公司 | Mainboard detection circuit |
| CN111596606A (en) * | 2020-04-03 | 2020-08-28 | 福建星云电子股份有限公司 | Fool-proof wiring method for connector |
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