去耦电容计算器
选择合适的去耦电容值以滤除电源噪声。
Input Power
7.33 W
Input Power vs Input Voltage
公式
## Switching Regulator Efficiency ### Formulas **P_in = P_out / Efficiency** **I_in = P_out / (Efficiency x V_in)** Switching regulators convert voltage using rapid switching and an inductor. They achieve 85-95% efficiency regardless of voltage ratio, far better than linear regulators for large step-downs.
计算示例
12 V to 3.3 V at 2 A with 90% efficiency.
- 01P_out = 3.3 x 2 = 6.6 W
- 02P_in = 6.6 / 0.9 = 7.33 W
- 03I_in = 7.33 / 12 = 0.611 A
- 04Power lost = 7.33 - 6.6 = 0.73 W
常见问题
Buck vs boost vs buck-boost?
Buck steps voltage down, boost steps up, buck-boost can do either. Choose based on your input vs output voltage relationship.
What affects efficiency?
Switching frequency, inductor DCR, MOSFET Rds(on), diode losses, and controller quiescent current all reduce efficiency.
Why not always use switching regulators?
They generate switching noise (EMI). Linear regulators are preferred for noise-sensitive circuits like ADCs and audio.
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