Power Amplifier Efficiency Calculator (PAE & Drain Efficiency)
Calculate RF power amplifier efficiency including power-added efficiency (PAE), drain efficiency, DC power consumption, and heat dissipation
Formula
PAE = (Pout − Pin) / Pdc × 100%
How It Works
Power amplifier efficiency is a critical parameter in radio frequency (RF) electronic design, representing the ratio of output RF power to total input power consumed by the amplifier. In an ideal scenario, an amplifier would convert all input power to useful output power, but practical limitations mean some energy is always lost as heat. Class A, AB, and C amplifier designs have different efficiency characteristics, with Class B and Class C designs typically offering higher efficiency but potentially lower linearity.
Worked Example
Example: A power amplifier consuming 10W of DC power and producing 7W of RF output power. Efficiency calculation: η = (Output Power / Input Power) × 100% = (7W / 10W) × 100% = 70% efficiency. This demonstrates how engineers can quantify an amplifier's performance and energy conversion capabilities.
Practical Tips
- ✓Always measure input and output power under consistent operating conditions
- ✓Consider temperature effects on amplifier efficiency
- ✓Use appropriate impedance matching for maximum power transfer
- ✓Select amplifier class based on specific application requirements
Common Mistakes
- ✗Neglecting thermal management and its impact on efficiency
- ✗Assuming linear relationship between input and output power across all operating conditions
- ✗Overlooking parasitic components that reduce actual efficiency
Frequently Asked Questions
What is a good power amplifier efficiency?
Efficiency varies by amplifier class: Class A (25-35%), Class AB (50-70%), Class C (70-90%)
How does frequency affect power amplifier efficiency?
Higher frequencies typically introduce more losses due to parasitic elements, potentially reducing overall efficiency
What factors impact power amplifier efficiency?
Key factors include amplifier class, operating frequency, load impedance, bias conditions, and semiconductor technology
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