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Calculadora de Selección de Disipador

Determina la resistencia térmica máxima del disipador requerida para mantener una temperatura de unión segura.

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Fórmula

θSA=TJ(max)−TAPD−θJC−θCS\theta_{SA} = \frac{T_{J(max)} - T_A}{P_D} - \theta_{JC} - \theta_{CS}
θ_SA — Required heatsink thermal resistance (°C/W)
T_J(max) — Maximum junction temperature (°C)
T_A — Ambient temperature (°C)
P_D — Power dissipation (W)
θ_JC — Junction-to-case thermal resistance (°C/W)
θ_CS — Case-to-heatsink thermal resistance (°C/W)

Cómo Funciona

Heatsink selection is a critical thermal management process for electronic components, focusing on preventing thermal failure by managing heat dissipation effectively. The thermal resistance calculation determines the maximum allowable thermal resistance between the semiconductor junction and ambient environment, considering key parameters like maximum junction temperature, ambient temperature, and power dissipation.

Ejemplo Resuelto

Problem: Select a heatsink for a transistor with Tj_max of 150°C, Ta of 25°C, Pd of 10W, θJC of 2°C/W, and θCS of 1°C/W Solution: 1. Calculate θJA_required: (150°C - 25°C) / 10W - 2°C/W - 1°C/W = 12.2°C/W 2. Apply 10% derating: 12.2°C/W * 1.1 = 13.42°C/W 3. Select a heatsink with thermal resistance ≤ 13.42°C/W

Consejos Prácticos

  • ✓Always verify component datasheet for specific thermal specifications
  • ✓Consider airflow and mounting orientation
  • ✓Use thermal interface materials to improve heat transfer

Errores Comunes

  • ✗Ignoring ambient temperature variation
  • ✗Neglecting component-specific thermal resistance
  • ✗Failing to apply manufacturing derating factor

Preguntas Frecuentes

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