As electronic devices to higher transmission speeds and more compact development, the connector also followed this trend, so chip connectors, fiber optic connectors, cable broadband fine pitch connectors and connectors for a variety of portable / wireless electronic device connector products is expected to become the next star product. On the other hand, with the Chinese consumer electronics, network design, communication terminal product yield rapid growth and global connector production capacity continues to shift to China, China has become the world's fastest growing and largest connector market. PCB connector on the bottom-contact connector has a standard 4-8 circuits, the rated current and voltage 0.3A and 50V, can be used for 0.12mm thick FPC cable. It has a unique BackFlip fixture in tight spaces for easy cable insertion and removal, as well as a super FPC cable clamping force.
printed circuit board connector
Printed circuit board connector PCB connector is also called , is an electronic connectors, printed circuit board connections and fixed devices designed to connect , usually push- pin , with superior FPC cable clamping force.
Relevant parameters of the printed circuit board connectors
* Contact resistance (CONtact Resistance)
* Resistance to electric current (Current Rating)
* Capacitance characteristics (Capacitance)
* Inductance characteristics (Inductance)
* Characteristic group of anti- (Characteristic Impedance)
* Signal delay characteristics (Time Delay)
* Other high frequency characteristics , such as Cross Talk EMI
Mechanical Specifications (Mechanical Specifications)
* Normal contact force (Contact Force Or Normal Force)
* Terminal pullout force (Pin Retention Force)
* Connect the separation force (Unmating Force)
* Mating cycles (Durability)
* A single contact point of insertion , extraction force (Engagement Force, Separation Force)
* Joint strength (Peeling Force)
Environmental Characteristics Specification (Enviromental Specification)
* Solder (Solderability)
* High temperature life / low life expectancy (High / Low Temperature)
* Thermal shock resistance (Thermal Shock)
* Temperature and humidity test (Temperature / Humidity Test)
* Salt spray test (Salt Spray Test)
* Coating perforation test (Porosity Test)
* Vibration test (Vibration Test)
* Impact Test (Shock Test)
Notes on the printed circuit board connectors
1, on the printed board design connector terminal number is not displayed . Printed circuit board design and carry out cabling jobs, in order to cover the triangular mark as a benchmark.
2, When welding on welding , soldering , please observe the following conditions .
Less than 260 ℃ 1 0秒300 ℃
Within 5 seconds 350 ℃ 3秒
3, external forces applied to the cable due to the PCB connector means does not eliminate the stress , so the length of the cable to leave a sufficient margin to prevent the cables to external influence .
4, on the terminal when using repeated bending terminals , the terminals may cause breakage , so please pay attention .
5, Use on the cover when the cover assembly into the base , or removed, if applied to the edge of the cover is too large displacement , will likely lead to breakage , so please pay attention .
6, on cable crimping tool cable cutting tool and crimp tool use special tools .
Works
Its working principle is: usually in the insulating material by a predetermined design, made of printed circuits, printing member or a combination of both conductive patterns called printed circuits. Providing electrical connection between the conductive pattern on the insulating base material components, referred to as printed wiring. This put printed circuit or printed circuit board called the finished printed circuit boards, also known as PCB or printed circuit board.
Industrial environments
Gold pads on the PCB to reduce PCB board edge ... in industrial environments, the use of technology to produce press-fit connectors can remain stable, Right Angle PCB ... This satisfied the small connector suitable for a variety of unmanned aerial vehicles , especially suitable for the work environment is extremely harsh UAV environment ... the connector uses the advantages of UAV applications is: excess supply of small basic PCB connector forcing its price fell 3% 10%. Manufacturers said that due to high input costs, the price trend will then gradually slow down.
Application of connectors for printed circuit boards
Printed circuit board connectors are used to connect between the PCB and the board , connectors , electronic connectors, communication equipment connectors, backplanes and communication equipment for the sub- board connectors , backplanes and industrial control sub- board connectors , precise and reliable connection.
Development trends of the printed circuit board connectors
1, miniaturization
Small size, light weight, small Pitch, reduced height , high density / high Pin Number
2, high-frequency signal / transmission
Low resistance contact with the group , low inductance , signal shielding effect , signal delay , Crosstalk .... and other effects
3, automation
Reducing the work station process , Auto Pick & Place, SMT Type, improve product accuracy , maintenance mode
4, Human Interface
User-friendly operation, foolproof design.
5, low cost
Product standardization, flexible product and process design , delivery and compression
Three basic properties of the connector
The basic properties of the connector can be divided into three categories: namely, mechanical properties, electrical properties , and environmental performance.
1, Mechanical properties on connectivity , the insertion force is important to mechanical properties. Insertion force insertion and extraction force is divided into ( pull force known as separation force ) , the two requirements are different. There are in the standard minimum and maximum insertion force required separation force , which indicates that , from the use point of view , smaller insertion force ( LIF to have low insertion force and the insertion force ZIF no structure ) , while if the separation force is too small , it will affect the contact reliability .
Another important mechanical properties are the mechanical life of the connector PCB . Mechanical life is actually a durability (durability) indicators in the national standard GB5095 call it mechanical operation . It is the first time you insert and pull out of a cycle to cycle after a specified PCB plug connector can normally complete its connectivity features ( such as contact resistance value ) as the basis for evaluation .
PCB connector insertion force and mechanical life with the contact structure ( positive pressure size ) contact area coating quality ( coefficient of sliding friction ) as well as contacts arranged dimensional accuracy ( degree of alignment ) related.
2, main electrical performance electrical properties , including PCB connector contact resistance , insulation resistance and dielectric strength .
① high-quality electrical contact resistance PCB connector should have a low and stable contact resistance . PCB connector contact resistance from a few milliohms to tens of milliohms range.
② measure insulation resistance between the insulation performance indicators PCB electrical connector contacts and the contact member and the housing , on the order of hundreds to thousands of megohms megohm range.
③ said dielectric strength or resistance, voltage, medium voltage, tolerance is the ability to characterize PCB connector between contacts or contacts with the housing rated test voltage .
④ other electrical properties.
EMI leakage attenuation evaluation PCB connector electromagnetic interference shielding effect , the leakage of electromagnetic interference attenuation evaluation PCB connector electromagnetic interference shielding effect , generally in the 100MHz ~ 10GHz frequency range tested.
RF coaxial connector on the PCB is concerned , there is the characteristic impedance , insertion loss, reflection coefficient , voltage standing wave ratio (VSWR) and other electrical indicators . Due to the development of digital technology, in order to connect and transmit high-speed digital pulse signal , the emergence of a new class of high-speed signal PCB connector PCB connector that , accordingly, the electrical properties , in addition to the characteristic impedance , but also the emergence of some new electrical indicators, such as crosstalk (crosstalk), propagation delay (delay), time delay (skew) and so on .
Circuit board cable
How to achieve normalization circuit board cable
Achieve normalization circuit board cable
Specifications of wire can be easily obtained from a variety of data in , but how to use these parameters to calculate the resistance PCB connector it ? This article will introduce to calculate the resistance of cable wire size and printed circuit board using the relationship between the size of the cable , as well as the size and function of the resistance and the temperature between the PCB design.
You can get the electrical wires associated with the size parameters from a variety of publications and manuals lot of information (commonly referred to as wire specification) . But how to use this information to analyze the printed circuit board connector parameter data are few. The following describes the relationship between the wire and cable specifications between the area and how to use a function of cable resistance and the size and temperature.
Background Information
American Wire Gauge (AWG) system, established in 1857 by the JR Brown, known as Brown & Sharp (B & S) specifications. From wire production process can know the diameter of the wire is gradually reduced through a series of holes drawn from the wire specifications drawn largely reflects the number of steps required . For example, a specification of the wire 24 than 20 specifications for wire Dora four times. Specifications are listed in the current conductor and the corresponding diameter and cross-sectional area of the table .
These steps are not all the data in a specific definition , but one thing is consistent : Specification 0000 ( 4/0 ) , which is defined as the diameter of 0.4600 inches; Specification 36 , with a diameter of 0.0050 inches . Other specifications of the geometric dimensions are between two points. If these dimensions are evenly distributed between any two adjacent diameter ratio is given by (Note: Between 0000 and specifications Specifications 36 Total 39 ) .
In fact, the diameter of the specifications are not uniform distribution . Any two adjacent tables and calculation of the ratio between the diameter of the result of the formula is very similar, but because of the multi-level error will accumulate and produce a great deviation , thus using the above formula to calculate the value is an approximation rather than the actual value .
The formula
In diameter , the diameter of the wire used for the specification of the number of the graph , there is a visible increase of the diameter of the rules, the number of the wire diameter and wire size is almost a straight line curve . The curve equation is: Specification = -9.6954 - 19.8578 × Log10 (d), where d is the wire diameter in inches .
PCB cable cross section is rectangular rather than circular . Thus , in cross -sectional area can be defined as a variable equation as follows: Unit = 1.08 + 0.10 × Log10 (l / a), where a is a cross -sectional area in square inches.
When the conductor cross-sectional area is known, can be calculated by the formula equivalent wire sizes . Conversely, the wire size is known, the following formula can be calculated cross-sectional area cable through : Area = l / (10 (10 × Specifications - 10.8 ) )
Wire resistance
Provide specifications of the Central Standing Committee in wire size table some parameter values . These parameters can be estimated by a length of the wire resistance . The calculation of cable resistance is slightly more complicated than the lead resistance calculations. Each relationship has a resistivity of metal (sometimes also called the characteristic resistance ) , resistivity, wire length, and the cross-sectional area between the resistor: R = ρ×l/a
Wherein R is the resistance in ohms , l is the length of the wire , a is the cross-sectional area . Units by the ohmic resistance coefficient and length expressed in units . The resistivity of copper is usually : ρ = 1.724 ( Micro Europe - cm ) or ρ = 0.6788 ( Micro Europe - cm )
This parameter can be calculated with any copper cable resistance , ie resistance coefficient divided by the cross-sectional area of the cable , and the cable length is multiplied . It must be noted , the resistivity changes with temperature , the resistivity is usually given at 20 ℃ resistivity . Thus, the resistivity of the resistance value of the resistance calculated from the ambient temperature of 20 ℃ .
Cable resistance increases with temperature , the parameter known as the " temperature coefficient of resistance ," may indicate the size of this change , by the following formula to calculate the effects of the parameters on the size of the resistor : R2/R1 = 1 + 0.00393 × ( T2-T1)
Wherein R1 and T1 , respectively, and the reference temperature for the reference resistor (in ℃). The new temperature T2 , R2 is the resistance at the new temperature .
All these calculations are very tedious . UltraCAD Design has introduced a free calculation tool that can be downloaded from the website UltraCAD www.ultracad.com. With this tool , the equivalent wire size , thickness or width of a given line connecting any two of the parameters, the other parameters can be calculated . It can calculate the resistance in the case of cable length and temperature of a given calculation connecting line voltage drop at a given current.
Solder layer
Finally , we analyze the changes in the solder layer on the cable resistance . Any conductor resistance is a function of its resistivity , the analysis can be connected in parallel lines and the solder layer treated as a conductor . Assuming the solder layer and the connection line having the same width and length , and the need to consider the thickness of the solder layer of the cable .
Resistivity of copper is 1.724 micro-ohm - cm, while tin resistivity of 11.5 micro-ohm - cm , 6.7 times higher than copper . Lead resistivity of 22 micro-ohm - cm , about 13 times higher than copper . Accordingly, the ratio of tin and lead solder content resistivity higher than the solder layer is approximately the same thickness as the copper cable 10.
Because resistance is inversely proportional to the size of the shunt conductor of the same thickness of the copper and the solder layer, about 90 % of the current flowing through the wire ( residual current through the solder layer ) . Therefore, usually in a non- negligible impact on the accurate measurement of cable solder layer resistance and voltage drop .
About PCBway
Since 2003 PCBWAY has been the leading PCB quick turn manufacturer specializing in both Prototype and Production quantities, Initially produced single-sided and double-sided printed circuit boards for the consumer electronics market. PCBWAY is ranked among the top 4 board fabricators in asia and is well-known for its expedited turn time capabilities and its reliable best on-time shipping record.
Today, we have over 450 operators with high modern facilities to manufacture multi-layer PCB up to 12 layers. Backing up with a group of professional engineers, and well established quality system. PCBWay has grown to become a major PCB manufacturer in Asia to serve in diverse customers base such as electronics appliance, communication, educational electronics, power supplies, Automationsetc.
Our mission is to become one of leading PCB manufacturer that provide in high quality product with total customer satisfaction.
