Featured programme / PRG-2507
A radar module rescued from a single-source allocation
This one is included because the failure had nothing to do with soldering. The customer's design was sound and the first three builds were clean; what put the programme at risk was an antenna-adjacent component on allocation with a lead time that moved from 12 to 46 weeks inside one quarter.
The constraint
A 24 GHz presence-sensing module for building automation, six layers on FR-4 with a profiled antenna section, an impedance tolerance of plus or minus 8% on two controlled lines, and 11,000 units a year released against demand windows rather than a smooth schedule. Packaging was 0201 passives and two 6 x 6 mm QFN devices under a removable shield can.
The plan and the outcome
We re-panellised from two-up to four-up on 1.0 mm FR-4, qualified and documented a second source for the allocated part rather than substituting silently, X-Rayed both QFNs on every board, and moved the antenna section through an impedance-verified route with a coupon measured per lot. A finished-goods buffer was set for the three customer demand windows. Across five production lots the first-pass yield has held at 95.2%, panel utilisation is 26% higher than the original two-up layout, and on-time delivery stands at 98.6%. No board has shipped on the second source without the customer's written approval and a documented validation build.
Featured programme detail - PRG-2507
| Stackup |
6 layers, FR-4, 1.0 mm finished thickness, ENIG finish |
| Panel |
4-up, 220 x 160 mm usable area, 1.6 mm breakaway rails |
| Placements |
412 per board, 0201 passives, two 6 x 6 mm QFN |
| Reflow peak |
243 C, SAC305, soak profile on a 10-zone convection oven |
| Inspection |
100% AOI, X-Ray on both QFNs and on the shield-frame perimeter |
| Electrical test |
Flying probe on the pilot, functional test with RF power measurement in volume |
| Release volume |
11,000 units a year in three demand windows |
| Bring-up |
12 working days from data release to first article |