贴片电阻代码计算器
解读贴片电阻上的数字代码和阻值。
V
A
耗散功率
0.5000 W
Power (mW)500.00 mW
Power Dissipated vs Voltage Across Component
公式
## Power Dissipation **P = V x I** Also: **P = I^2 x R** and **P = V^2 / R**. All forms are equivalent via Ohm's Law.
计算示例
5 V across a component at 100 mA.
- 01P = 5 x 0.1 = 0.5 W = 500 mW
- 02Ensure component is rated above 0.5 W.
常见问题
Why does it matter?
Excess heat damages components and reduces reliability.
How to reduce dissipation?
Lower voltage, reduce current, or use a more efficient component.
Safe margin?
Derate by 50%: use a 0.5 W resistor for 0.25 W dissipation.
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