High-TG PCBs
TG refers to the Glass Transition Temperature, it’s a critical characteristic of PCB substrate which measures the heat resistance capability. And it’s also the tipping point from where the substrate transitions from a glassy state to a rubbery state. It’s 30℃ (Celsius Degree) higher than the Max. working temperature of PCB raw materials and 40℃ higher than the Max. operating temperature of the electronic devices.
High-TG PCBs, can also be regarded as High Temperature PCBs, meaning PCBs designed to withstand different high temperature environments (e.g. lead-free reflow soldering and harsh external operating conditions).
According to the different high temperature resistance capabilities, FR4 PCBs can be classified in to Standard TG PCBs, Medium TG PCBs and High TG PCBs.
| PCB TG Types | TG Values (DSC) | Applications |
| Standard TG PCBs | 130℃ – 140℃ | Common Consumer Electronics |
| Medium TG PCBs | 150℃ – 155℃ | Delicate Electronics Working Under Higher Temperature Ranges |
| High TG PCBs | 170℃ – 225℃ | Communication Equipment, Automotive Electronics, Industrial Control Equipment, Aerospace, Medical Devices, Military and Defense, Precise Instruments and LED Lighting etc. |
Characteristics of High TG PCBs
● Higher Thermal Stress Resistance
● Improved Mechanical Performance
● Higher Power Density
● Better Plated Through Hole Reliability
● Stronger Delamination Durability
High TG Materials Used By X-Parts
| Materials | TG (DSC, °C) | Td (WT, °C) | CTE-z (ppm/ °C) | Td260 (Min.) | Td288 (Min.) |
| IT180A | 190 | 345 | 45 | 60 | 20 |
| S1000-2/2B | 185 | 345 | 45 | 60 | 20 |
| S1170G/GB | 180 | 390 | 45 | 60 | 60 |
| S1141 | 175 | 300 | 55 | 8 | / |
| Rogers RO4350B | 280 | 390 | 32 | / | / |
X-Parts High-TG PCBs Manufacturing Capabilities
| Features | Capabilities |
| Layer Count | 2-64L |
| TG Values | 170℃, 180℃, 185℃, 190℃, 200℃ & Higher |
| High TG Materials | S1141, S1170G/GB, S1000-2/2B, IT180A, RO4350B, RO4003C, RO4835, RO4833, FR408, FR408HR, FR370HR, IS410, N4000-12, N4000-13/13SI, N4000-13EP/EPSI, N4000-29, N4380-13RF, N4350-13RF, N4800-20/20SI, N7000-2 HT |
| Board Thickness | 0.2 MM – 3.2 MM |
| Maximum Dimensions | 580 MM x 1080 MM |
| Copper Thickness | 0.5 OZ – 14 OZ |
| Minimum Track / Spacing | 0.075 MM / 0.075 MM |
| Minimum Drill | 0.15 MM Mechanical, 0.1 MM Laser |
| Surface Finish | ENIG, Immersion Tin, Immersion Silver, Electrolytic Gold, Gold Fingers (HASL / HASL LF Not Recommended) |