Capability Specification

Below is a summary of the manufacturing capabilities available at PWT Ltd.


  Readily Available. No consultation needed.


  Within Capability, but may be design dependant or require slightly longer lead time.


  Entirely design dependent and only available after consultation.

Definition Standard Tight Development
Base Material FR4 (tg135)
FR4 (tg>150)
Rogers 4003
Rogers 4350
Rogers RT/Duroid
Pyralux (DuPont)
Metal Backed (IMS)
 Surface Finish Lead Free HASL Imm Silver
ENIG (Imm Gold) Standard HASL
E’lytic (hard) Gold Imm Tin
Carbon Ink Ohmegaply
 Solder Resists Green
Pyralux (coverlay)
                     Minimum Feature 0.1 0.076
 Legend White
                      Minimum Feature 0.154
 Peelable Resist Blue
 Maximum PCB Size 381 x 432 419 x 470
 Minimum Track & Gap 0.1016 0.076
 Maximum Aspect Ratio 8:1
 Minimum PCB thickness 
                      2 layer 0.2
                      4 layer 0.5
                      6 layer 0.7
                      8 layer 1
                      10 layer + 1.27
 Maximum Copper Weight
                      Inner layers 3oz
                      Outer layers 4oz
 Minimum Hole (Drilled) 0.2 0.1
 Minimum Plated Slot (dia.) 0.5
 Minimum Annular Ring 0.127 0.076
 Minimum Inner Layer Clearance 0.254 0.203 0.152
 Minimum distance feature to profile 0.254 0.127

Microvia at PWT

As many of our current and prospective customers will know; this year PWT have been working to bring a microvia service to our already extensive offering, in support of our customers increasing HDI requirements. We are pleased to announce that we are now offering microvias commercially and look forward to servicing our customers even better in the future with this new technology.

What are PWT’s capabilities?

Due to continued investments in skills, resources and equipment; we have been able to push on with challenging projects to further enhance our offering. As a result you may not be up to date with our current capability.

PWT offer track and down to 3 thou (0.076) in support of our new microvia offering; as well as impressive capabilities with respect to drilling and registration of high layer count multilayers. In addition to FR4; PWT are experienced in Polyimide, Rogers and Rogers/Hybrid materials.

We also handle a lot of blind/buried via; both blind drilled and sequentially built, and controlled impedance manufacture. We are rightly valued by our customers for our responsiveness; so if you aren’t sure about a particular technology, talk to us on 01707 338871.

Controlled Impedance

PWT has invested heavily in Polar Speedstack PCB Stack-up Builder, Si8000m QuickSolver & Coupon Generator software.

This enables us to not only check customers supplied builds & that their impedance requirements will be met during manufacturing, but also advise customers on specific builds for PCB’s where only a known Impedance requirement is in place.

  • Using this new software, PWT can simulate any build to check the Impedance characteristics to ensure the correct layer separations and track/gap widths before manufacturing commences.
  • Test coupons that are manufactured along with the boards are tested through the manufacturing process. The results are automatically logged and stored for traceability.
  • PWT will control the Impedance to a tolerance of +/- 10% as a standard. If you require a closer tolerance than 10%, then please contact our Technical team for further assistance.

For further information regarding your Controlled Impedance requirements, please contact our Technical Team.