An SMT line seen down its length: pick-and-place machine, reflow oven and boards travelling on the conveyor

Trust layer · our own line · Bao'an, Shenzhen

Our own PCB & PCBA factory

Do we make anything ourselves, and what does that give you on a partner-built product? It is the engineering backstop, and it is never counted among the 24 sites.

Book a factory visit Send us your spec

01What this factory is

Fabrication, assembly and test under one roof.

45,000 m²500+ people9 SMT + 5 DIP

What it is Our own PCB & PCBA factory in Bao'an Fabrication, assembly and test in one plant, with 9 SMT and 5 DIP lines running a lead-free process.

How it counts Never counted among the 24 partner sites It is a separate line of the business, shown as a strip. It is never named on this site, and it is not one of the 24.

What it buys you An engineering baseline, and a place to argue a spec The board under a partner-built product is read by the engineers who assess our own, and a spec can be settled on a real line.

Published envelope Up to 58 layers 45,000 m², 500+ people and a fabrication envelope that reaches 58 layers, detailed in the table below.

A wide production floor from a raised viewpoint, three rows of identical assembly machinery and painted walkways — Fig. 01One floor, both processes. Fabrication and assembly share one site, so a stackup question is a walk away.

Pick-and-place heads and feeder reels aligned along a single SMT line, seen close down the line — Fig. 02Nine SMT lines, five DIP lines. The line count is a published figure; the speeds are not, and the next section says why.

An oblique elevated view of a container yard, long parallel rows of identical containers stacked two high with even aisles between them — Fig. 03A backstop, not the catalogue. The products a buyer orders are made by the 24 sites, not by this plant.

Five finished power products staged in one row: a rack battery shelf, a supercapacitor module, a CRPS module, a vertical PDU and a coupling manifold plate — Fig. 04Where our boards end up. Inside units like these, built by the sites we represent, not by this plant.

02Capability · the envelope we publish

What the capability table states.

1–58 layers0.1 mm trace0.15 mm drill

Fabrication and assembly envelope, as the factory's own capability table states it
Parameter	Published value	Basis
Fabrication	1–58 layers; minimum trace and space 0.1 mm; board thickness 0.2–3.2 mm	Capability table
Copper and holes	Outer copper 1–8 oz, inner 1–4 oz; PTH ±0.08 mm; NPTH ±0.05 mm	Capability table
Minimum drill	0.15 mm, with a minimum annular ring of 0.15 mm	Capability table
Assembly	9 SMT and 5 DIP lines on a lead-free process, with bare-board electrical test and AOI	Line list
Acceptance	IPC-A-610J at the class the buyer specifies; J-STD-001J governs the process	Both dated March 2024

A production panel of identical bare boards held in a white inspection fixture, gold pads and teal solder mask — Fig. 05Layer count is a fabrication limit. It decides what a stackup can ask for.

Five items in one level row on a pale ground: a blank lot tag, a shallow tray of identical boards, a test fixture, a sealed module and a sealed carton — Fig. 06Every envelope line has a record. Lot identity, test data and a sealed unit behind it.

Digital calipers closed around a machined aluminium housing beside a blank inspection checklist and a sealed sample bag — Fig. 07Tolerances are measured, not asserted. A ±0.08 mm hole is checked with an instrument and logged.

A fan of finished TFT and OLED display modules overlapping on a plain surface, blank grey screens and ribbon tails — Fig. 08The board is rarely the product. Most of what runs through the line ends up inside something else.

03Mechanism · test on our own line

What is tested here, and to which document.

IPC-6012FIPC-A-600MIPC-7711/7721D

Bare board Flying-probe electrical test and AOI Laser stencils are cut from 304 HTA stainless to ±0.003 mm, so the paste deposit is a controlled variable rather than a guess.

X-ray Void judgement to IPC-7095 Followed deliberately instead of IPC-A-610, because that standard's scope states it gives no X-ray criteria.

Class 3 Cross-section and coupons Where the buyer specifies Class 3, coupons are sectioned to IPC-6012F and IPC-A-600M: the coupon is what makes a claim checkable.

Rework Governed by IPC-7711/7721D At Class 3 some joints are not reworkable. Which ones, and what happens instead, is agreed before production starts.

A cross-sectioned plated through-hole seen through a microscope objective, the copper barrel wall and the laminate layers in clinical laboratory light — Fig. 09A claim becomes physical here. The copper barrel and the laminate are what a plating claim is checked against.

An engineer's test bench in a dim clean room with a rack-mount oscilloscope, a bench power supply and a board assembly under a magnifier arm — Fig. 10Measurement needs an instrument. Bench equipment sits beside the magnifier, not in a photograph.

An engineering bench under an inspection lamp with a finished board assembly, a magnifier arm and sample connectors — Fig. 11Every build gets a written review. Stackup, class, test coverage and open questions, in one document.

04Trust layer · why the board

The trust floor, not the subject.

Every product has a board insideWe own the board

A finished populated circuit board assembly standing upright on edge with a matte black heatsink across its upper half

B-01

Where a product usually fails first

Every product in the network has a board inside it. It is the part we build ourselves, so we meet the failure mode early.

1–58 layers9 SMT + 5 DIP

Our own line · Bao'an, Shenzhen

Three items on a plain background: a microscope eyepiece, a sealed sample bag with a blank label and a plain laboratory courier box

B-02

The same baseline under both sides

Partner parts share the engineering baseline of our own factory, so the same engineers can read a partner's stackup and answer for the answer.

IPC-A-610 acceptanceJ-STD-001 process

Applied on both sides · one framework

Three finished fanless industrial computers in a row, closed enclosures with no boards visible

B-03

And it stays in one section

The board narrative explains why we can judge a supplier. What a buyer can order is the larger part of this website.

24 partner sites12 categories

Trust floor · not the subject

05Trust layer · stated plainly

What we can prove today, and what we will not claim.

No invented figuresEmpty beats invented

We can prove Lines, layers, materials and tolerances Line counts, the layer range, materials and finishes, test coverage, and every tolerance the factory's capability table states.

We do not publish Placement speed, zone counts, yield, on-time rate Not placement speeds in CPH, not reflow zone counts, and not first-pass yield or on-time delivery for our own line, until measured data supports them.

For comparison only Partner figures are partner figures Partner sites publish 75,000–80,000 CPH placement and 98.7%–99.7% yield. Those belong to those sites and are not transferable to ours.

The rule behind it A partner envelope is not ours A published partner capability is never evidence for our own line, so the two sets of numbers are kept apart on this site.

Empty is acceptable here. Invented is not: the fields above stay blank until the factory's own measurements exist.

Five finished objects in one level row on a plain pale surface, including a rack battery shelf and a machined coupling pair — Fig. 12Products, not promises. What leaves the network is a finished unit with a record attached.

A single technical drawing sheet on a pale surface with a pen, dividers and one tab marking a clause — Fig. 13A missing figure is survivable. An unverifiable one is not, which is why the field stays empty.

A technical drawing flat on a pale bench with digital calipers, a drafting triangle and sample parts resting on it — Fig. 14Ask for the measurement. Any figure on this page can be traced to the table or the record behind it.

A wide empty industrial service corridor in one-point perspective, a painted walkway line running to a closed roller shutter — Fig. 15Come and measure it. Anything not published here can be checked on the line in person.

06Execution layer · visiting the line

See the line, not a framed document.

Invitation letterItineraryVisa support

Booking A hosted tour, with interpretation A factory visit is part of the China visit service: invitation letter, itinerary, visa support, a hosted tour and interpretation throughout.

What we do not show No certificate walls We do not photograph certificate walls or factory signage, and no certificate holder name or number appears on this site.

One trip, two views The backstop and the production source The same week can cover partner sites in the network, so a buyer sees our line and the line that will actually make the order.

Visitors in anti-static coats walking an assembly-hall aisle between rows of SMT machines, seen from behind — Fig. 16Visits are scheduled around production. The line runs; it does not stop to be presented.

A dense industrial district at blue hour, rows of low factory roofs and container yards receding toward a pale horizon — Fig. 17Bao'an, Shenzhen. The site address on any document has to match the place you walk through.

A macro view of a printed circuit board cut edge under laboratory light, the alternating copper and dielectric layers of the stackup — Fig. 18Bring the file with you. A visit is where open questions in the assessment get closed in person.

Related China visit & factory tours Engineering & solutions team

07Trust layer · the boundary

Where this page stops.

Service line 4 of 6The engineer signs it

A bright assembly hall seen down a central aisle between two rows of identical SMT machines — AA factory cannot certify your design. Stackup, tolerances, thermal path and test coverage still have to be assessed against it.

A finished board assembly in a machined housing beside a bare multilayer production panel resting in a white inspection fixture — BThe assessment is a deliverable. A written review and optimisation plan, signed by the engineer who wrote it.

A finished populated circuit board assembly for a power supply laid flat on a pale bench, photographed from directly above — CThe reason a partner's board gets questioned. Even when your product is not a board, this page is why the question gets asked before the order.

This page is the separate strip: our own line, 45,000 m² in Bao'an with 500+ people, 9 SMT and 5 DIP lines and fabrication up to 58 layers. It is never counted among the 24 partner sites and is never named on this site.

The PCB & PCBA category How quality is controlled

08Start

Book a factory visit.

Send the design or the specification first. The visit is more useful once the open questions are on the table.

Recorded. An engineer will reply.

We answer from eric@dfshk.cn.

Plan the trip eric@dfshk.cn · +86 152 3512 7440