With the fast growing demands of In Vehicle Computers, multi applications and complicated system integration over In Vehicle Computers are more and more important. Nowadays, In Vehicle Computer is already a powerful control center built-in with different wireless modules (GPS/Wi-Fi/3.5G/Bluetooth) and controls several peripherals in vehicle. By the requirements of highly integrated system structure with build-in wireless modules, good CPU performance, wide range operating temperature and fanless design, In Vehicle Computers thermal problem becomes a challenge to makers.
How to solve thermal problem of In-Vehicle Computers:
The easiest way to reduce heat for thermal problem is to use low voltage or even ultra-low voltage CPU. This kind of CPU has lower TDP and generates less heat. But at meanwhile, it has poor CPU performance and high cost.
Instead of the easy way, we devote in the thermal design of the whole system. We analyze the system thermal model and design optimized heat sink and heat pipe solution to solve thermal problem. By this way, we can use general mobile CPU to keep good CPU performance and cost, at the same time, we still have good thermal performance in our system.
Heat sink and heat pipe thermal solution:

Comparison table for General Mobile CPUs and Low Voltage CPUs:
Product Name |
Core? Duo Processor T2500 |
Core? 2 Duo Processor T5500 |
Core? 2 Duo Processor T7400 |
Core? Duo Processor L2400 |
Core? 2 Duo Processor L7400 |
Code Name |
Yonah |
Merom |
Merom |
Yonah |
Yonah |
Processor Number |
T2500 |
T5500 |
T7400 |
L2400 |
L7400 |
# of Cores |
2 |
2 |
2 |
2 |
2 |
# of Threads |
2 |
2 |
2 |
2 |
2 |
Clock Speed |
2 GHz |
1.66 GHz |
2.16 GHz |
1.66 GHz |
1.5 Ghz |
L2 Cache Cache |
2 MB |
2 MB |
4 MB |
2 MB |
4 MB |
System Bus |
667 MHz |
667 MHz |
667 MHz |
667 MHz |
667 MHz |
Instruction Set |
32-bit |
64-bit |
64-bit |
32-bit |
64-bit |
Max TDP |
31 W |
34 W |
34 W |
15 W |
17 W |
Intel? Turbo Boost Technology |
No |
No |
No |
No |
No |
Intel? Hyper-Threading Technology |
No |
No |
No |
No |
No |
Intel? Virtualization Technology (VT-x) |
Yes |
No |
Yes |
Yes |
Yes |
CPU Performance (PassMark) |
963 |
921 |
1237 |
792 |
868 |
Intel Recommended Channel Price |
$264 |
$177 |
$265 |
$278 |
$297 |
We use T2500 / T5500 / T7400, while other makers use L2400 / L7400.
You can see (T2500 / T5500 / T7400) CPU performance is better and cost is lower. L2400 / L7400 are more expensive with lower performance. The only benefit of them is lower TDP.
Since we solve the heat problem and can enjoy the benefits of general mobile CPU performance with lower cost. So why not! |