Printed Circuit Board Assembly (PCBA)

With over 30 years of expertise as a UK based electronics contract manufacturer Prima continually invests in the latest production equipment and ensures its skilled team members are fully trained so that we can deliver a broad range of high-quality Printed Circuit Board assembly services including:

Working closely with customers, our experienced technical team can take projects from the initial prototyping phase and rapidly move into full-scale production.

Key service features:

Quality: stringent inspection and test procedures, Prima delivers products right first-time, regardless of the complexity level to ISO9001 and ISO13485 accredited standards. PCB assemblies go through an extensive Automatic Optical Inspection (AOI) procedure. X-ray inspection and additional specific testing can also be carried out.

Expertise: we take care of your electronics manufacturing requirements - from prototyping and new product introduction (NPI) through to volume production. We leverage our engineering and technical team’s long-established know-how and experience of delivering project of various complexities and requirements.

PCB Assembly

Surface Mount Assembly (SMA)

Prima utilises Surface Mount Technology (SMT) which means electrical components or surface mounted devices (SMD) are efficiently and quickly fixed directly onto the PCB without the need for insertion of leads into pre-drilled holes.

SMA at Prima is carried out using multiple, high-precision screen printers for accurate application of solder paste, modern Pick-and-Place machines capable of placing components down to 01005 size formats including automated placement of Ball Grid Array (BGA) devices. We can offer both convection and vapour phase reflow processes to our customers, depending on requirements.

For SMA we use the following machinery:

Solder paste application: Europlacer SP710 screen printers

Pick-and-place machines:

o Europlacer iineo+ machines. The SMT component placement machine iineo+ is a multi function SMT Pick-and-Place platform and has the highest level of flexibility and feeder count in the industry. All heads and all nozzle positions can place the full range of components – making it extremely flexible and efficient.

o Yamaha S20 machines. These machines have a high feeder capacity and are capable of processing large boards as well as handling a wide range of components.

Kurtz Ersa HOTFLOW 3/14 Reflow oven that delivers exceptional soldering results on account of its superior thermal performance. It can take boards up to 508mm and it is perfectly designed for in-line production.

Automatic Optical Inspection (AOI): Omron RNS-pt. This AOI instrument enables high-precision inspection of the PCB using a colour highlight system, dome illumination, high resolution of 10 µm, a colour vector judging method and an automatic calibration. The Omron can inspect for missing components, component shifting, polarity error, wrong components, presence of solder, bridging, solder balls.

• Solder paster printing:

First, we setup the screen printer to print the RoHS compliant solder paste on the boards. The paste travels through a stencil that has been prepared in advance. After printing the paste, the boards are inspected to see if there is sufficient paste on the pads, then they are ready for the Pick-and-Place machine.

• Pick-and-Place:

SMT Component reels that are fed into the machine are prepared and are double-checked by a second person. The machine is programmed with essential information using the Pick-and-Place files. The machine mounts the components on the boards. The boards exit the Pick-and-Place machine and are inspected before entering the reflow oven using an inspection conveyor.

• Reflow oven:

The boards enter the oven and move across several heating zones to ensure a gradual increase of temperature. Within a few minutes the solder is reflowed, and the components are now completely soldered to the boards.

• Automatic Optical Inspection AOI and X-ray

Finally, the boards go through an extensive AOI procedure to check solder joints, look for skewed or tombstoned parts, as well as uncovering orientation issues and solder bridges. Any corrective actions required are immediately made offline and checked prior to release. We also carry out X-ray inspection in cases where AOI is unable to effectively identify fault conditions. The inspection is carried out using a Nordson Ruby X-ray machine (with X-Plane tilt facility). This 360° inspection will reveal hidden problems - including bond wires inside devices, co-planarity issues with BGAs, plating variation of the vias or micro-vias.

Surface Mount Assembly process

Through-Hole Build
(Conventional PCB Assembly)

Although, it is apparent that the electronics manufacturing industry continues to move towards SMT PCB assembly, there are applications and situations where Through-hole assembly is still required. We have the experience, expertise, equipment, and selective soldering capabilities needed for high-quality Through-Hole PCB assembly required in the market.

We typically hand assemble Through-hole components and manually solder the parts. We use flow soldering or the Pillarhouse Jade S-200 MKII selective solder machine, which can solder the toughest thermal pins. Importantly, all workmanship is to IPC- 610 standards and all Through-Hole assemblies go through an extensive inspection.

Mixed assembly methods

We can perform Through-hole and SMT assembly on the same board. Conventional (Through-hole) assembled parts are typically added after SMT assembly.

PCB Assembly Rework and Modification

Prima have completed many advanced PCBA rework and modification projects successfully using our expertise and sophisticated rework equipment. If you need PCBAs reworked from simple passive component replacements to complex BGA replacements, we can help.

Services include but not limited to:

- Removal, replacement and addition of components

- BGA device removal and replacement

- Modifications to circuit tracks and circuit profile


Our prototyping service supports our customers’ new product introduction (NPI) process, enabling them to quickly generate a functional prototype that is fully inspected. These prototypes can then be used for demonstration as well as tested by end-users in the field for valuable design validation and design refinement.

Following prototyping we can support with any required modifications or improvements and later with full product assembly (Box Build). All prototypes are manufactured on the main production lines to ensure rapid progress into full-scale production. Find out more

• SMT, Through-hole and mixed assembly method

• Single and double sided SMT Assembly

• PCBA Testing and inspection services (including X-Ray)

• PCB Assembly Rework and Modification

• Prototyping

Summary of Capabilities

Certifications and Memberships

Your Design. Expertly Built.

© 2022 Prima Electronic Services Ltd,

4 Harding Way, St Ives, Cambs, PE27 3WR

Phone: 01480 498338

Company No. 02247539

VAT Reg. No. GB638593203

Your design, our solution

© 2020 Prima Electronic Services Ltd,

4 Harding Way, St Ives, Cambs, PE27 3WR

Phone: 01480 498338

Company No. 02247539

VAT Reg. No. GB638593203