Top 10 ICT Test Probe Manufacturers for PCB Testing and Test Fixtures

Many of the circuit boards inside smart plugs, hubs and sensors are checked on an in-circuit test (ICT) fixture before they ship. That fixture is a "bed of nails": a plate of spring-loaded probes that touch test pads on the assembled board and measure whether each component and solder joint is doing its job. The probes decide whether a good board passes and a bad one gets caught, so choosing the right ict probes manufacturer is as much a quality decision as a purchasing one.

This guide covers ten manufacturers that publish usable specifications for ICT and board-test probes. It is not a quality ranking. Each company fits a slightly different fixture, board density or volume, so the sections below explain what to compare first and then what each maker publishes.

What to Compare Before You Choose

Probe datasheets look similar, but a few details decide whether a fixture runs cleanly or throws false failures.

• Test center and receptacle: Probes sit in receptacles on standard centers, usually 100 mil (2.54 mm), 75 mil (1.91 mm) or 50 mil (1.27 mm). Match the grid and confirm the receptacle type, not just the pitch.

• Spring force at working travel: Published options run from about 0.6 N to 4 N on common 100 mil probes. More force pushes through flux residue and oxide, but it also stresses the board. Fixtures for lead-free boards with heavy residue often need more force than clean assemblies.

• Working stroke versus full stroke: A common 100 mil probe has about 6.35 mm of full travel and a recommended working stroke near 4.3 mm. Design the fixture inside the working range. Bottoming out shortens probe life.

• Tip style and plunger diameter: Crown, spear, serrated, flat and cup tips suit different pads. A plunger that is too wide can bridge adjacent traces on tight layouts.

• Contact resistance and current: Typical datasheets list 3 A to 8 A and resistance from under 20 mΩ to about 100 mΩ. Lower resistance helps when measuring low-value components. Higher current ratings matter for power-rail test points.

• Cycle life against cost: Rated life ranges from a few thousand cycles to several hundred thousand. Match it to the number of boards each probe will touch before you plan to change it.

• Supply: Sample availability, minimum order quantity, tip customization and lead time all affect a fixture build schedule.

10 ICT Test Probe Manufacturers Worth Shortlisting

Figures come from each manufacturer's published material or major distributor listings. Specifications vary by series, so check the datasheet for the exact part.

1. Promax

Promax keeps its ICT range small and specific, with three catalog probes for different jobs. The PT137A200-3340A is a high-force probe (200 gf) with a 0.90 mm plunger, under 20 mΩ contact resistance and a 3 A continuous or 10 A instantaneous rating, aimed at power-rail test points. The PT100T58-1715C is a compact 17.15 mm probe at 58 gf for tight layouts. The PT078B160-3460A is a 34.6 mm standard probe with a 0.50 mm plunger, rated for at least 200,000 cycles.

The company says it builds probes for 100, 75 and 50 mil receptacles, sets no fixed minimum on catalog parts, typically asks for 500 to 1,000 units on custom designs, and supplies free samples. It holds ISO 9001, ISO 14001, ISO 45001 and IECQ QC080000. Note how the catalog shows the usual trade-off: the 200,000-cycle probe lists under 185 mΩ, while the 3,000-cycle high-force probe lists under 20 mΩ.

2. INGUN

INGUN Prüfmittelbau GmbH, a German test-contact specialist, lists its GKS-100 series as standard-stroke ICT and functional test probes on a 2.54 mm grid. Ratings are 5 A on most variants and 8 A on some, with typical resistance under 100 mΩ, 6.35 mm maximum stroke and a 4.3 mm recommended working stroke. Spring force at working stroke runs from 0.6 N to 4 N depending on the variant, and tip diameters span 0.5 mm to 1.9 mm. Probes fit KS-100 receptacles.

3. Feinmetall

Feinmetall's F100 probes target the 2.54 mm grid at 5 A maximum continuous current, with typical contact resistance of 30 mΩ and 6.4 mm maximum travel. Its F703 series covers the tighter 1.9 mm grid at 4 A and 50 mΩ typical. A long-life gold finish is offered for extended endurance. Feinmetall also lists high-current, switch and short-travel probes, which is convenient when one fixture needs several probe types from a single source.

4. PTR HARTMANN

PTR HARTMANN publishes detailed ICT series by grid. The 1012/E covers 75 mil with 6.4 mm full travel, 4.3 mm working travel, 3 A to 4 A and 20 mΩ typical or lower. The 1025/E covers 100 mil at 5 A to 8 A, with spring force at working travel from 0.6 N to 4 N. Long-travel versions reach about 11.7 mm, and its 2028 series includes high-temperature variants rated to +250°C. Matching extraction and insertion tools for receptacles are also listed.

5. Everett Charles Technologies (ECT)

ECT's distributor catalog lists ICT and functional test probes on 50, 75 and 100 mil centers. A typical 75 mil probe shows 6 A, 10 mΩ average resistance, 6.35 mm full travel, 33 mm length and a 500,000-cycle rating. The company says it has made custom spring probes for over 50 years, which suits fixtures that need an unusual length, travel or tip.

6. Smiths Interconnect

Smiths Interconnect's ICT-100 series on 0.100" centers uses a bifurcated barrel with four separate fingers. The barrel is formed against the plunger to remove the gap between the two parts, which the company says makes resistance more accurate and stable than standard designs. Ratings are 3 A, spring force options run from 3.5 oz to 10 oz, and overall length reaches 1.46" (37.08 mm). A lead-free version builds on the same design.

7. QA Technology

Based in Hampton, New Hampshire, QA Technology says it has served the electronics test industry for over 25 years. Its range includes in-circuit and functional probes, Socketless X probes, high-current probes and double-ended probes for ATE interfaces. The company designs and builds its own production equipment, and it has added integraMate hyperboloid contacts for connector markets.

8. LEENO Industrial

LEENO, founded in 1978 and headquartered in Busan, South Korea, offers over 1,000 standard ICT probe types and says they can be customized. That breadth helps when a fixture mixes pad sizes and heights. The company also makes IC test sockets and RF test sockets, so semiconductor and board-level testing can come from one supplier.

9. CCP Contact Probes

CCP began in 1986 as a specialized provider of test probes, with ICT among its first lines, and is listed on the Taiwan Stock Exchange. It publishes an ICT probe catalog covering P and R series probes, and has subsidiaries in the United States, Germany, Japan and Korea. A sample listing, the P-02D-0515, shows a 24.70 mm probe rated at 3 A with 100 mΩ contact resistance and 2.54 mm full travel.

10. Nidec Advance Technology (formerly Nidec-Read)

Nidec's spring probes for PCB testing cover standard pitches from 0.5 mm to 3.0 mm for bare-board and PCB fixtures. Its high-force types cover 1 mm to 2.54 mm pitch, with a choice of tip and spring force at each pitch. It also makes MEMS spring probes with very small springs and plungers, which suits fine-pitch fixtures where conventional barrels are too large.

Match the Probe to the Board

Start with your fixture's grid, then your board's pad size, residue level and test volume. Those four facts narrow ten manufacturers to two or three. Order samples of each shortlisted probe, run them on a real board for a few thousand touches, and track contact resistance and false failures. A datasheet shows what a probe can do on a bench, and a trial on your own boards shows how it behaves in your production line.