About the introduction of Rigid-flex PCB

 1. Classification of Rigid-flex PCB

  It can be divided into two categories of products: rigid-flex composite PCB and rigid-flex PCB. Rigid-flex composite PCB is the PCB that combine Flex PCB and rigid PCB together in the manufacturing process. There are common blind hole and buried hole designs among them. Therefore, higher-density circuit design is possible. And the technology of the Ridgid-flex PCB is to make the flex PCB and the rigid PCB separately and then press them into a single circuit board with signal connection but no through-hole design. But at present, the commonly used “rigid-flex board” collectively refers to all rigid-flex board products without subdividing the two.

 2. The advantages of rigid-flex PCB

  The rigid-flex PCB is flexible, can be wired three-dimensionally, can change shape according to space constraints, is resistant to high and low temperature, flame resistance, can be folded without affecting the signal transmission function, can prevent electrostatic interference, stable chemical changes, stability, and reliability High, which is conducive to the design of related products, can reduce assembly man-hours and errors, and improve the service life of related products, so that the size of the application product is reduced, the weight is greatly reduced, the function is increased, and the cost is reduced.

 3. Application of rigid-flex PCB

  Industrial use-Industrial use includes rigid and flexible boards used in industry, military and medical. Mobile phone-the application of soft and hard boards in mobile phones, such as folding mobile phone turning point (Hinge), image module (Camera Module), button (Keypad) and radio frequency module (RF Module), etc. are common. Consumer electronic products-Among consumer products, DSC and DV are representative of the development of soft and hard boards. Automobile-In the use of soft and hard boards in automobiles, there are commonly used buttons on the steering wheel to connect to the motherboard, the connection of the car video system screen and the control panel, the operation connection of the audio or function keys on the side door, the reversing radar imaging system, and the sensor (Sensor, including air quality, temperature and humidity, special gas regulation, etc.), vehicle communication system, satellite navigation, rear seat control panel and front-end controller connection board, vehicle exterior detection system, etc.

4 LAYERS FLEX PCB MANUFACTURER

Flex PCB solution

 Darlox Electronic Limited offer flexible and rigid-flex PCB fabrication services including prototype and production . Quick turn design and manufacture of low-to-high volume rigid-flex, and flex PCB quantities with industry for rigid-flex and high density interconnects (HDI) PCBs.   Contact us now to help with your critical flex circuit solution.

PCB services.

Rigid-flex PCBs High quality rigid-flex printed circuit boards design and manufacture	Flex PCBs Flexible printed circuit design and manufacture for all applications
Flex PCBs with Impedance Control Design of flex circuit board with characteristic impedance and EMI Shielded	Multilayer Flex Circuits Single, double, and multilayer flex and rigid-flex circuits.

Why choose us to make flex PCB?

As a leading prototype-to-production flexible PCB supplier, Darlox have a large production capabilities for flex and rigid-flex PCB capabilities. As a professional flexible circuit manufacturer, we build boards with circuit width spacing down to 0.75 mil and 1 mil micro vias. Contac us now with our flex PCB design and engineering services team to help you determine what the optimal technologies are for your project's application. We also offer extremely fast quick turn flex circuit prototyping services. Contact us to learn more about  our full flexible and rigid-flex capabilities.

Design of circuit board with characteristic impedance

 Characteristic impedance: In the Custom 4 layers flex circuit board industry, the ‘impedance control’ is generally blurted out but it’s not strictly correct. The professional term should be “Characteristic Impedance Control”. Because the “things” that “circulate” in computer PCB circuits are not currents, but are aimed at the transmission of square wave signals or pulses in energy. The “resistance” encountered during transmission of this “signal” is also called “characteristic impedance”, and its symbol is Zo. Calculation formula: In the electronic mechanical transmission signal line, the resistance encountered during the propagation of the high-frequency signal or electromagnetic wave is called the “characteristic impedance” (the combined effect of electrical impedance, capacitive reactance, and inductive reactance). It is used to evaluate the uniformity of the circuit and the uniformity of the thickness of the dielectric layer. The relationship with inductance and capacitance is:

In the formula, L is the inductance value and C is the capacitance value. However, the unit of Zo is still “ohm”. It can be seen that the commonly called “impedance control” is actually not a “control” for the “impedance” of alternating current.

Impedance Control (Impedance Control): Refers to the “resistance” that a certain circuit layer (Signal Layer) generates to its related layer (Reference Plane usually refers to the closest ground layer) under a high-frequency signal during transmission. It must be controlled within a rated range to ensure that the signal is not distorted during transmission.

In the formula, L is the inductance value and C is the capacitance value. However, the unit of Zo is still “ohm”. It can be seen that the commonly called “impedance control” is actually not a “control” for the “impedance” of alternating current.

Impedance Control (Impedance Control): Refers to the “resistance” that a certain circuit layer (Signal Layer) generates to its related layer (Reference Plane usually refers to the closest ground layer) under a high-frequency signal during transmission. It must be controlled within a rated range to ensure that the signal is not distorted during transmission.

Please refer the below pic shows:

Rigid Flex PCB

CUSTOM 2 LAYERS FPC WITH FR4 AND STEEL STIFFENER

 CUSTOM 2 LAYERS FPC WITH FR4 AND STEEL STIFFENER

As one of the leading flexible circuit manufacturers, Darlox offer a range of flexible circuits design and manufacturer including 2 layers, 4 layers, 6 layers and 8 layers with shielding, impedance controling customized. You can specify single sided PCB, double sided PTH and multilayer and our team will deliver.

2 Layer - 1 Day Turn	2 Layer -  3 Day Turn	4 Layer - 5 Day Turn
10" x 16" Max Board Size	Max. Board Size: 60 sq. in.	Max. Board Size: 30 sq. in.
Min. Order Quantity:  1	Min. Order Quantity:  3	Min. Order Quantity:  4
FR-4 .062" Material	FR-4 .062" Material	FR-4 .062" Material
I oz. Cu.	I oz. Cu.	I oz. Cu.
Tin Finish	Lead-Free Solder Finish*	Lead-Free Solder Finish*
No Mask (bare)	Green Mask	Green Mask
No Legend	White Legend (1 or 2 Sides)	White Legend (1 or 2 Sides)
Custom Shape¹	Custom Shape	Custom Shape

A brief introduction to rigid flexible printed circuit board technology

 Rigid-flexPCBs solution is a good choice to many applications on electronic devices. Many designers will face the pressure to build more and more dense electronic devices, and more importantly, they will have to reduce manufacturing costs and shorten manufacturing time. 

Rigid flexible printed circuit boards are likely to become a trap new technology for novices to succeed. Therefore, it is wise to understand how to make flexible circuits and hard and soft connectors. In this way, we can easily find hidden dangers in the design and prevent problems. Now, let's see what basic materials are needed to make these circuit boards.

Substrate and protective film

In more applications, we need more flexible plastic films than epoxy resins. Our most commonly used material is polyimide (PI), which is very soft and strong, not easy to tear or stretch. It also has incredible thermal stability and can easily withstand temperature changes during reflow soldering. During temperature fluctuations, we can hardly find its expansion and contraction.

Polyester (PET) is another commonly used flexible circuit material. Compared with only polyimide (PI) film, its heat resistance and temperature deformation are worse than PI film. This material is usually used in low-cost electronic equipment, and the printing line is wrapped in a soft film. Since PET cannot withstand high temperatures, let alone soldering, flexible circuit boards are made through a cold pressing process. 

PI film, PET film, thin epoxy resin and glass fiber core are commonly used materials for flexible circuits. In addition, the circuit also needs to use other protective films, usually PI or PET films, and sometimes also need to shield the resistance welding ink. The protective film can protect the conductor insulation from corrosion and damage, and the thickness of the PI and PET films is in the range of 1/3 mil to 3 mils, of which 1 mil or 2 mils are usually used. Glass and epoxy materials are relatively thick, usually 2 to 4 mils.

Electric conductor

The copper conductors are a common choice.  The best choice is electrolytic copper foil for responding to the circuit board reducing manufacturing time and cost. Electrolytic copper foil can also increase the current carrying capacity by increasing the weight of copper, so as to obtain the possible width of the copper plate, such as a planar inductor.

As we all know, copper is relatively poor in work hardening and stress fatigue. If the flexible circuit needs to be folded or displaced repeatedly in the final application, advanced rolled tempered copper foil (RA) is a better choice. Obviously, more rolling toughening processes will inevitably increase costs, but before fatigue fracture, the rolled toughened copper foil can be bent and folded more times. It increases the elasticity in the Z deflection direction that we need, and it makes us live longer in applications where we often bend and roll. Because the rolling toughening process extends the grain structure in the plane direction.

 After the copper foil passes through the high-pressure roller, its grain structure can be extended in the plane direction, making the copper softer and increasing the elasticity of the z-axis. A typical example is the connection between the bracket and the cutter head, or the laser head in a Blu-ray drive (shown below).

In the Blu-ray machine, a flexible circuit is used to connect the laser to the main circuit board. Note that the flexible circuit on the circuit board on the laser head needs to be bent at a right angle. Glue balls are used here to enhance the connection of the flexible circuit.

Article from:http://www.darlox.com

CUSTOM 2 LAYERS FPC WITH FR4 AND STEEL STIFFENER

Rigid Flex PCB Manufacturer

FFC (FPC) welding method and points to be attention

 FPC is an abbreviation of Flexible Printed Circuit. It uses a thin insulating material with a high bending rate to form an adhesive layer on a film-shaped insulator and a conductive foil on it, which can be bent freely.

FFC is the abbreviation of Flexible Flat Cable, a flat cable that is made by sandwiching conductors placed in parallel on the left and right in a thin film insulator, and the contacts are tin-plated, which is cheaper than FPC.

1. Parts of the soldering machine

· Pulse heater-used for crimping FFP (FPC) and TPH by pressure.

· Lower heater-used for preheating and heating.

· Camera (such as CCD camera)-used to observe and adjust the TPH and FFC (FPC) terminals to a fixed position.

2. The specific welding method of FFC (FPC)

· Apply flux to the outside of TPH.

· Align the terminals of TPH and FFC, use the lower heater and pulse heater adjusted to the appropriate temperature, and crimp the terminals of both TPH and FFC at the same time.

· Adjust the temperature, keep it for a few seconds, and cool down after welding.

Darlox supplying flexible flat cables, flexible printed circuit cables, screen data and signal cable based on LVDS technolgoy, high voltage cables, inverter cables, and shielded cables. Quick sample prototypes and fast production lead time are both guaranteed. Please click here to custom your ffc cables if you cound not find the right cables you want on the page.

Flexible flat cables Flex printed circuits

Mobile Phone 1S, 3.7V, 1.5A Flexible Circuit PCM Protection Module Board for Lithium-ion Battery Pack with NFC Communication

Digital Product Protection Board (FPC) Flexible Circuit PCM Protection Module Board for battery

● Working current: 0.5-5A, reaching 10A in an instant;

●Basic functions:

2 charging overvoltage protection 4.20V-4.465V, charging overcurrent protection, charging high and low temperature protection -20 degrees - +50 degrees;
2 discharge overvoltage protection 2.5V-3.0V, discharge overcurrent protection, discharge high and low temperature protection -20 degrees - +65 degrees;
2 short circuit protection;
2 secondary protection;
2 0V charging;
2 automatic sleep;


●Maximum imposition size: L (150mm) * W (135mm) * T (0.15mm);

●PCB type: FPC full soft board, soft and hard board, soft + hard board;

● Copper thickness 0.5OZ (18um), 1OZ (35um);

● Layer: double panel, four layer board (hard board)

●Ink color: butter, black oil, red oil

● Reinforcement method: FR-4, steel sheet, PI

● Pad processing: Shen Jin, OSP;

●With plastic rolled copper, no rubber rolled copper, rubberized electrolytic copper, glueless electrolytic copper

●Golden fingers: bright gold, semi-bright and half-dumb, full dumb gold;

●Applicable environmental requirements: ROHS, REACH, halogen-free, 7P;

●Applicable equipment: applications and mobile phones, tablets, MP3/MP4, digital cameras, Bluetooth headsets, motor drive boards, intelligent robots and other products.