This guide provides best practices and component specifications for constructing reliable Dev Pro series test fixtures. The Dev Pro series offers professional-grade features for development work requiring higher precision and durability than standard Dev fixtures.
Guide Pins#
GP-2TL guide pins are the preferred method for accurately locating the DUT within the fixture. These pins provide consistent engagement with board mounting holes.
For smaller locating holes (2.5-3mm), design custom cradles mounted with M3 screws. The cradle captures board features when standard pin engagement isn't possible due to hole size constraints.
Pressure Pins#
All Dev Pro fixtures should use 35mm pressure pins. Secure pins to the pressure plate with M3 x 10mm screws.
The shorter pin length compared to Dev fixtures (35mm vs. 45mm) matches the Dev Pro's different mechanical configuration and DUT height positioning.
Receptacles and Probes#
Centalic PQ50/PQ100/PE75 probes and the corresponding RQ50/RQ100/RE75 receptacles are recommended for Dev Pro fixtures. These provide professional-grade performance suitable for higher cycle counts and more demanding applications.
Probe Tip Selection#
| Test Point Type | Recommended Tip |
|---|---|
| Standard test points | B tips |
| Populated through-holes | A tips |
| Specialized applications | Ingun star-type |
B tips are the standard choice for Dev Pro fixtures. A tips suit through-hole contact requirements. Star-type probes from Ingun address specialized test point geometries.
Assembly Specifications#
DUT Positioning#
Position the DUT at an 11.22mm Z offset to achieve optimal probe contact and pressure distribution during fixture closure. This is significantly higher than the Dev series (3.5mm), reflecting the Dev Pro's different mechanical architecture.
Height Calculation#
The DUT height accounts for:
- 35mm pressure pins
- Centalic receptacle collar heights
- Dev Pro cartridge and plate stack-up
Key Differences from Dev Fixtures#
| Aspect | Dev | Dev Pro |
|---|---|---|
| Guide pins | GP-2UL | GP-2TL |
| Pressure pins | 45mm | 35mm |
| Receptacles | Generic | Centalic series |
| DUT height | 3.5mm | 11.22mm |
| Typical cycle life | 1,000 | 10,000+ (with G10 cartridge) |
The Dev Pro's professional-grade components justify the higher initial cost through extended fixture life and more consistent test results.
Probe Plate Design#
Design the probe plate with cutouts to avoid interference with tall components on the DUT. The Dev Pro's parallel stroke mechanism requires clearance planning to prevent binding during fixture closure.
When to Choose Dev Pro#
Select Dev Pro over standard Dev when:
- Expected cycle count exceeds 1,000 tests
- Test result repeatability is critical
- The product design is stable (not rapidly iterating)
- Budget supports higher-quality components
- Parallel stroke mechanism benefits test consistency
Related Documentation#
- Fixture Bases — Dev Pro base specifications
- Dev Pro Maintenance — Replacement parts and service
- Cartridges — G10 cartridge options for extended life
- Dev Fixture Guidelines — Standard Dev comparison