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Creative & Custom LED Displays 4-in-1 COB Prototype for AT&T Retail Pillars
Following AT&T's successful 630-unit P2.5 pillar rollout, the next question was inevitable: which pixel pitch for flagship stores? Rather than months of theoretical debate, DOIT VISION engineered a 4-in-1 prototype pillar with P1.25, P1.538, P1.86 COB, and the original P2.5 SMD all on a single unified chassis. Delivered in 14 days, AT&T decision-makers walked around the pillar comparing resolutions side by side. More importantly, 100% backward compatibility means these new COB modules are millimeter-level drop-in replacements for the existing 320x160mm chassis, future-proofing 630 deployed pillars.
At a Glance
Which Pitch for Flagship?
After deploying 630 P2.5 SMD pillars across Costco locations, AT&T's next logical question was whether flagship stores warranted a higher-resolution upgrade. But debating pixel pitches over spec sheets and renderings would take months with no resolution — everyone has an opinion on paper, but seeing is deciding.
DOIT VISION proposed a radical shortcut: build a single prototype pillar with all four candidate pitches mounted side by side, running the same synchronized content. Decision-makers could physically walk around the pillar, compare resolutions at actual viewing distances, and decide in minutes instead of months of meetings.
Millimeter-Level Drop-In Replacement
The engineering mandate was non-negotiable: every new COB module must be a literal drop-in replacement for the existing 320x160mm SMD modules across all 630 deployed pillars.
Magnetic cylinder positions, CNC alignment pin holes, hub board interfaces, and power routing — every physical interface dimension was matched down to the millimeter. The 320x160mm universal footprint guarantees that as LED technology advances, AT&T's structural investment in the pillar chassis and Costco store infrastructure remains fully protected.
The biggest challenge: P1.25 COB and P2.5 SMD have completely different PCB thicknesses, mask designs, and resin encapsulations. At the 90-degree corner where two different-pitch modules meet, distinct CNC milling profiles were required for each module type to achieve a visually seamless join — a tolerance challenge standard single-pitch pillars never face. Each module's aluminum frame edge was individually profiled to compensate for its specific thickness and mask geometry.
Project Specs
From Pitch Debate to Physical Prototype
Lock the Question
AT&T needed a side-by-side pitch decision for flagship stores — not another PDF comparison. We defined four pitches on one chassis: P1.25 / P1.538 / P1.86 COB plus the original P2.5 SMD.
Unified Chassis Design
Kept the 320×160mm magnetic footprint identical across all four pitches. CNC-profiled mixed-pitch 90° corners so each module type seats flush without chassis redesign.
14-Day Build
Fabricated the 4-in-1 pillar, loaded synchronized content, and burn-in tested so decision-makers could walk around live pixels — not CAD renders.
Drop-In Upgrade Path
Proved COB modules install into the existing 630-unit fleet chassis with zero tooling change — literal drop-in when flagship stores select a finer pitch.
Planning a product upgrade path?
Multi-pitch prototypes eliminate months of debate. See all your resolution options on one chassis, running synchronized content. Prototype delivery in 2 weeks.
Frequently Asked Questions
Can I compare different LED pitches on a single prototype?
How does backward compatibility work for LED module upgrades?
How fast can you deliver a multi-pitch comparison prototype?
What happens when different pitch modules meet at a 90-degree corner?
Can existing P2.5 pillars be upgraded without replacing the chassis?
Do COB modules need a different controller than the original SMD pillars?
Which pitches were compared on the AT&T 4-in-1 prototype?
What is the typical MOQ for a multi-pitch prototype program?
Products & Resources
Fine Pitch LED Displays
COB Pro, COB Beta, MIP & All-in-One. Pixel pitches from P0.62.
Explore →AT&T 630-Unit Mass Production
The original P2.5 pillar rollout. 30-day production, CNC corners, BrightSign.
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Indoor, COB, foldable & trifold poster displays. P1.5 to P3.0.
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