OPUTE | APPLICATION CASE STUDY
Thermal Gel Solution for Outdoor COB LED Display Driver ICs
How OPUTE TP-30 helped improve thermal performance and temperature uniformity in an outdoor LED display module.
Application: Outdoor COB LED display driver ICs | Material: OPUTE TP-30 one-component thermal gel | Thermal conductivity: 3.0 W/m·K
01. The Thermal Management Challenge
In COB (Chip-on-Board) LED displays, LED chips are mounted directly on the PCB and encapsulated as an integrated assembly. This supports fine pixel pitch and surface protection, but high component density creates a demanding thermal environment. The customer's outdoor COB module featured 76 driver ICs on the rear PCB, with an air gap between the IC surfaces and the metal rear housing.
Air has low thermal conductivity (approximately 0.026 W/m·K), so gaps between the ICs and housing can restrict heat transfer. A suitable thermal interface material (TIM) helps bridge this gap and conduct heat into the metal cover.
02. Why the Previous Thermal Grease Was Reconsidered
The customer initially used thermal grease because of its good initial surface wetting and simple manual application. According to the case records, after approximately two weeks of operation the module temperature rise increased and disassembly revealed oil–filler separation in the grease. The application involved outdoor temperature cycling and repeated thermal expansion and contraction.
Grease stability depends on its formulation and operating conditions; this case does not imply that all thermal greases will exhibit the same behavior. For this specific module, the customer sought a more stable, dispensable thermal interface.
03. OPUTE TP-30 Thermal Gel Solution
OPUTE TP-30 is a one-component thermal gel selected to bridge the driver ICs and the rear metal housing. Its gel structure is intended to retain the carrier material, conform to interface movement and support automated dispensing.
04. On-Site Dispensing Process
The customer used a four-step process: inspect the rear PCB, dispense TP-30 onto the driver ICs, check gel coverage, and assemble the rear cover with sealing adhesive. Closing the housing compresses the gel to establish contact between the ICs and the cover.
05. Thermal Imaging Comparison
In a thermal imaging comparison on the same module under the reported test conditions, eight measurement points used TP-30 thermal gel and the remaining 15 points used the original thermal grease.
Average: 53.6°C · Range: 2.2°C
Average: 57.7°C · Range: 6.9°C
The TP-30 measurement group also showed a 4.1°C lower average measured temperature in this comparison.
Test interpretation: These are different measurement points on one module, not a before-and-after reading at identical points. The reported difference is specific to this test setup and does not establish a universal performance advantage for all applications.
06. TP-30 Typical Technical Properties
| Property | Typical Value | Condition / Method |
|---|---|---|
| Appearance | Pink paste | Visual |
| Thermal conductivity | 3.0 ± 0.3 W/m·K | ASTM D5470 |
| Thermal resistance | 0.05 °C·in²/W | 20 psi · ASTM D5470 |
| Oil separation | ≤ 4% | 150°C × 24 h · ASTM G120-1 |
| Volatile content | ≤ 0.07% | 150°C × 24 h · ASTM E595-2006 |
| Volume resistivity | ≥ 3.2 × 10⁸ Ω·cm | Room temperature · ASTM D257 |
| Dielectric breakdown strength | ≥ 8.0 kV/mm | Room temperature · ASTM D149 |
| Extrusion rate | 35 g/min | Room temperature · 90 psi |
| Flammability rating | UL 94 V-0 | As stated in supplied case material |
Values reproduced from the supplied application case. Confirm current TDS and any certification documentation before final publication.
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OPUTE provides thermal interface materials for LED displays, power electronics and industrial applications. Contact us to discuss interface gap, assembly pressure, dispensing requirements and samples.
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