Calcolatore Impedenza Cavo Coassiale
Calcola l'impedenza caratteristica di un cavo coassiale dalle sue dimensioni.
Max Heat Sink θsa
6.00 °C/W
Max Heat Sink θsa vs Power Dissipated
Formula
## Heat Sink Sizing ### Formula **θsa_max = (Tj_max - T_ambient) / P - θjc - θcs** This gives the maximum thermal resistance the heat sink can have. Select a heat sink rated at or below this value. Forced air cooling reduces effective θsa.
Esempio Risolto
10 W device, Tj_max = 125C, theta_jc = 2, theta_cs = 0.5, ambient = 40C.
- 01Thermal budget = (125 - 40) / 10 = 8.5 C/W
- 02Used = 2 + 0.5 = 2.5 C/W
- 03Max theta_sa = 8.5 - 2.5 = 6.0 C/W
Domande Frequenti
What if the result is negative?
The component cannot stay within limits even with a perfect heat sink. Reduce power, lower ambient temperature, or choose a different package.
Does fan cooling help?
Yes. A fan can reduce heat sink theta_sa by 50-75%. Most heat sink datasheets list natural and forced convection ratings.
Thermal paste vs thermal pad?
Paste gives lower theta_cs (0.2-0.5 C/W) than pads (0.5-2 C/W) but is messier. Pads are easier for production.
Impara