Regulator Thermal Lab

Heat & Temperature Estimator for AMS1117 & LM78xx

Regulator Series

Output Version

Vin (V)

Vout (V)

Output Current (mA)

Typical max for AMS: 800mA | 78xx: 1.5A

Ambient Temp (°C)

Enter data and click calculate

Datasheet Notes:
• AMS1117: θ_JA ≈ 90°C/W (SOT-223). Dropout ≈ 1.1V.
• LM78xx: θ_JA ≈ 50°C/W (TO-220, No heatsink). Dropout ≈ 2.0V.
• Calculation: $P_d = (V_{in} - V_{out}) \times I_{out} + (V_{in} \times I_q)$.