Single Layer Flex Circuit With Branched Arms And ZIF Tail
A single layer polyimide flex circuit with a long main run, two branched arms and a stiffened ZIF tail. Flex replaces a wiring harness: one etched part carries every conductor, always in the same position, with no assembly variation between units.
What This Board Is
The circuit photographed runs the length of a mechanism, then splits into two shaped arms that land on separate sub-assemblies. Built as a harness this would be a dozen wires, two connectors and a jig. Built as flex it is one part with a stiffener under the ZIF tail. Minimum track and gap on our flex line are both 0.05 mm, which is 2 mil.
Coverlay is laminated over the etched conductors, then the outline is punched or laser cut to ±0.05 mm.
- Flex PCB
- 1 layer
- See specification
What You Get From This Build
- One etched part replaces a multi-wire harness, removing hand assembly and its variation
- Branched shapes reach separate sub-assemblies without splices or extra connectors
- Minimum track and gap of 0.05 mm (2 mil) fits many conductors into a narrow ribbon
- Laser and punch outline processes cut shapes that could not be routed on rigid material
Who Specifies This Board
- Camera, optical and lens module manufacturers
- Printer and scanner mechanism builders
- Medical instrument makers routing signals through moving joints
- Anyone replacing a hand-built harness that keeps failing final inspection
Four Failures This Build Is Designed Against
Each one is a real way this class of board goes wrong, and the tolerance or process decision that prevents it.
Harnesses routed slightly differently on every unit
An etched flex circuit is identical every time. Conductor positions are set by the artwork, not by whoever built it.
Wires that will not fit through the mechanism
A flex ribbon is a fraction of the thickness of a bundled harness and can be folded into the path available.
Splice joints that fail in the field
Branched shapes are etched as one continuous conductor, so there is no joint to fail.
Flex tails that buckle in a ZIF connector
A stiffener is laminated under the tail so it enters the connector square and holds its grip.
Technical Specification
Product detail from the catalogue record, followed by the published process capability for the Flex PCB family. Anything the legacy catalogue did not record is marked TBC rather than filled in.
| Item | Technical specification |
|---|---|
| Product name | 1 Layer Flexible PCB |
| Legacy catalogue reference | 1 Layer(FPC) |
| Product family | Flex PCB |
| Layer count | 1 layer |
| Surface finish | See specification |
| Layer count | Single layer, double layer and multilayer |
| Base material | PI, FR4, PET |
| Base copper thickness | 9, 12, 18, 35 and 70 µm |
| Maximum board size | 406 x 610 mm (16 x 24 in) |
| Minimum hole, drilled | φ0.1 mm (0.004 in) |
| Minimum hole, punched | φ0.5 mm (0.02 in) |
| Plated hole tolerance | ±0.05 mm (±0.002 in) |
| Minimum track width | 0.05 mm (2 mil) |
| Minimum track gap | 0.05 mm (2 mil) |
| Surface treatment | Plated or immersion tin, plated or immersion gold, OSP |
| Outline treatment | Precise V-cut, punch, milled, laser outline |
| Outline tolerance | ±0.05 mm |
| Coverlay | PI film and PET film lamination |
| Solder resist inks | LPI soldermask, UV-cured soldermask, legend ink, peelable soldermask, carbon ink, silver paste |
| Peeling strength | 1.0 kgf/cm with adhesive copper, 0.5 kgf/cm with adhesiveless copper |
| Legend colours | Multiple silk-screen colours |
What The Board Is Made Of
| Material | Specification |
|---|---|
| Base material | PI, PET or FR4 |
| Base copper | 9, 12, 18, 35 or 70 µm |
| Coverlay | PI film or PET film lamination |
| Solder resist | LPI, UV-cured, peelable mask, legend ink, carbon ink or silver paste |
| Adhesion | 1.0 kgf/cm with adhesive copper, 0.5 kgf/cm adhesiveless |
What Can Be Changed
- PI, PET or FR4 base material
- Base copper from 9 to 70 µm
- Stiffeners in any number of positions
- Plated or immersion tin, gold, or OSP
- Carbon ink and silver paste contact printing
- V-cut, punch, mill or laser outline
How This Board Is Made
Eight stages on equipment sourced from the USA, Japan, Germany and Israel. Every stage listed runs inside our own plant.
Material selection
PI, PET or FR4 base chosen against whether the part is soldered and how often it flexes.
Imaging and etching
Circuit etched to a 0.05 mm minimum track and gap.
Coverlay
PI or PET film laminated over the conductors with openings cut at the contact areas.
Stiffeners
Laminated where connector tails or component areas need to be held rigid.
Hole forming
Drilled to φ0.1 mm or punched to φ0.5 mm depending on the feature.
Surface finish
Plated or immersion tin, plated or immersion gold, or OSP.
Contact printing
Carbon ink or silver paste printed where a contact pad needs it.
Outline
Precise V-cut, punch, mill or laser to ±0.05 mm.
What Is Checked Before It Ships
- Peeling strength of 1.0 kgf/cm on adhesive copper and 0.5 kgf/cm on adhesiveless copper
- Outline tolerance verified at ±0.05 mm after punching or laser cutting
- Coverlay opening registration checked against the contact areas
- Plated hole tolerance held at ±0.05 mm
- Stiffener thickness checked against the connector insertion specification
What The Plant Holds
- ISO 9001:2000. Quality management system certification recorded by the company. Current revision year available on request.
- ISO 14001:1996. Environmental management system certification recorded by the company.
- UL. Certification recorded by the company. File number available on request.
- RoHS and lead free. Listed in the company environmental policy alongside pollution prevention and resource reduction.
Certificate numbers, issue dates and current revision years are not published on the legacy site. Ask for copies with your enquiry and they will be sent with the quotation.
How It Compares With The Alternatives
Three boards from our own catalogue, side by side, so the trade-off is visible rather than argued.
| Board | Layers or build | Finish | Best suited to |
|---|---|---|---|
| 1 Layer Flexible PCB | 1 | See specification | Harness replacement and branched interconnects |
| 1 Layer Flex Ribbon Cable | 1 | See specification | Straight multi-conductor ribbon runs |
| 2 Layer Flexible PCB | 2 | See specification | Circuits needing routing and contact pads on both sides |
What To Send With Your Enquiry
Four things that decide whether the quote comes back right the first time.
- Send the flat pattern with bend lines marked, plus a sketch of how the part folds in the assembly.
- State the bend radius at every fold and whether the fold is made once at assembly or repeats in service.
- Mark where stiffeners are needed and give the stiffener material and thickness.
- Give the ZIF connector part number so that the tail thickness and contact pitch can be matched.
1 Layer Flexible PCB Questions
What base materials do you use for flex?
PI, FR4 and PET, as published in our flex capacity table. Polyimide is the usual choice where the part will be soldered or will flex repeatedly.
What is the smallest hole you can put in a flex circuit?
0.1 mm drilled, which is 0.004 inch, and 0.5 mm punched.
Can you add stiffeners?
Yes. Tell us the stiffener material and thickness, and mark the area it covers on the drawing.
What outline tolerance do you hold on flex?
±0.05 mm, using precise V-cut, punching, milling or laser outline depending on the shape.
Other Boards In The Flex PCB Family
Boards built on the same line, with the same tolerances, in a different configuration.
Single Layer Flex Ribbon With Parallel Conductors And End Stiffeners
Double Layer Flex Circuit With Exposed Gold Contact Pads
Double Sided FR4 Board With Lead Free HASL
Four Layer Immersion Gold Board For Dense SMD Routing
Where This Board Is Used
The fields the legacy catalogue records for this class of board.
This Board In Context
Get 1 Layer Flexible PCB Priced Against Your Own Files
Send Gerber RS-274X with an NC drill file, or an ODB++ package, with the layer count, thickness, copper weight, surface finish and quantity. We check it against the published capability before quoting.