Depanel
Encyclopedia
Depaneling is a process step in high-volume electronics
assembly production. In order to increase the throughput of printed circuit board
(PCB) manufacturing and surface mount
(SMT) lines, PCBs are often designed so that they consist of many smaller individual PCBs that will be used in the final product. This PCB cluster is called a panel or multiblock. The large panel is broken up or "depaneled" as a certain step in the process - depending on the product, it may happen right after SMT
process, after in-circuit test
(ICT), after soldering
of through-hole elements, or even right before the final case-up of the assembly.
. It uses a router bit to mill the material of the PCB. You have to dispose of the bit after some time.
Routing requires that single boards are connected using tabs in a panel. The bit mills the whole material of the tab. It produces much dust that has to be vacuumed. It is important for the vacuum system to be ESD
-safe. Also the fixturing of the PCB must be tight - a usually aluminium jig or a vacuum holding system is used.
The two most important parameters of the routing process are: feed rate and rotational speed. They are chosen according to the bit type and diameter and should remain proportional (i.e. increasing feed rate should be done together with increasing the rotational speed).
Routers generate vibrations of the same frequency as their rotational speed (and higher harmonics), which might be important if there are vibration-sensitive components on the surface of the board. The strain level is lower than for other depaneling methods. Their advantage is that they are able to cut arcs and turn at sharp angles. Their disadvantage is lower capacity.
The disadvantages are: ability to cut in straight lines only and higher stress than for routing.
Electronics
Electronics is the branch of science, engineering and technology that deals with electrical circuits involving active electrical components such as vacuum tubes, transistors, diodes and integrated circuits, and associated passive interconnection technologies...
assembly production. In order to increase the throughput of printed circuit board
Printed circuit board
A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. It is also referred to as printed wiring board or etched wiring...
(PCB) manufacturing and surface mount
SMT
SMT may refer to:* Satisfiability Modulo Theories* Statistical machine translation* Scottish Mortgage Investment Trust PLC * Scottish Motor Traction, a former bus company in Scotland...
(SMT) lines, PCBs are often designed so that they consist of many smaller individual PCBs that will be used in the final product. This PCB cluster is called a panel or multiblock. The large panel is broken up or "depaneled" as a certain step in the process - depending on the product, it may happen right after SMT
Surface-mount technology
Surface mount technology is a method for constructing electronic circuits in which the components are mounted directly onto the surface of printed circuit boards . An electronic device so made is called a surface mount device...
process, after in-circuit test
White box testing
White-box testing is a method of testing software that tests internal structures or workings of an application, as opposed to its functionality...
(ICT), after soldering
Soldering
Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal into the joint, the filler metal having a lower melting point than the workpiece...
of through-hole elements, or even right before the final case-up of the assembly.
Main depanel technologies
There are five main depaneling cutting techniques currently in use, and a sixth is about to enter the market:- hand break
- pizza cutterPizza cutterA pizza cutter is a utensil that is used to cut pizzas. The use of a pizza cutter instead of a standard knife avoids the dislodging of loose toppings through the back-and-forth motion of the blade typical of a knife. Pizza cutters press their blade down vertically instead.-Varieties:There are two...
/ V-cut - punchPunch (tool)A punch is a hard metal rod with a shaped tip at one end and a blunt butt end at the other, which is usually struck by a hammer. Punches are used to drive objects, such as nails, or to form an impression of the tip on a workpiece...
- router
- sawSawA saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive...
- laser (new)
Hand break
This method is suitable for strain-resistant circuits (e.g. without SMD components). The operator simply breaks the PCB, usually along a prepared V-groove line, with the help of a proper fixture.Pizza cutter / V-cut
A pizza cutter is a rotary blade, sometimes rotating using its own motor. The operator moves a pre-scored PCB along a V-groove line, usually with the help of a special fixture. This method is often used only for cutting huge panels into smaller ones. The equipment is cheap and requires only sharpening of the blade and greasing as maintenance.Punch
Punching is a process where single PCBs are punched out of the panel through the use of special fixture. It is a two-part fixture, with sharp blades on one part and supports on the other. The production capacity of such a system is high, but fixtures are quite expensive and require regular sharpening.Router
Depaneling router is a machine similar to wood routerWood router
A router is a tool used to rout out an area in the face of a relatively hard workpiece, typically of wood or plastic. The main application of routers is in woodworking, especially cabinetry....
. It uses a router bit to mill the material of the PCB. You have to dispose of the bit after some time.
Routing requires that single boards are connected using tabs in a panel. The bit mills the whole material of the tab. It produces much dust that has to be vacuumed. It is important for the vacuum system to be ESD
ESD
ESD may mean:*Education for Sustainable Development, a vision of education as depicted by the United Nations*Educational service district, a state-level legislative grouping for schools in some US states....
-safe. Also the fixturing of the PCB must be tight - a usually aluminium jig or a vacuum holding system is used.
The two most important parameters of the routing process are: feed rate and rotational speed. They are chosen according to the bit type and diameter and should remain proportional (i.e. increasing feed rate should be done together with increasing the rotational speed).
Routers generate vibrations of the same frequency as their rotational speed (and higher harmonics), which might be important if there are vibration-sensitive components on the surface of the board. The strain level is lower than for other depaneling methods. Their advantage is that they are able to cut arcs and turn at sharp angles. Their disadvantage is lower capacity.
Saw
A saw is able to cut through panels at high feed rates. It can cut both V-grooved and not-V-grooved PCBs. It does not cut much material and therefore generates low amounts of dust.The disadvantages are: ability to cut in straight lines only and higher stress than for routing.
Laser (as of March, 2010)
UV laser cutting is now being offered as a sixth method by some equipment makers.External links
- OZO Support, LLC - Custom CNC Router/Drill/Depanel
- SAYAKA High Precision PCB Router
- CENCORP/PMJ automec - router and saw technologies company
- IPTE - company offering electronics manufacturing and test equipment
- Can Today's Depanelers Cut It? - article in Reed Electronics
- Depaneling: a study in yield and productivity: saw systems can provide a low stress and fast alternative to hand breaking methods
- CircuitPeople PCB Panel Calculator