A 432 MHz Class-D Power Amplifier with 60% Power Efficiency for Wireless Capsule Endoscopy

A 432 MHz power amplifier (PA) for wireless capsule endoscopy is presented. 180 nm CMOS process is used with a 1.8 V supply voltage. Class-D is chosen in order to meet the high-efficiency requirement. According to the post-layout Monte Carlo simulations, the PA achieves 60% power efficiency while delivering 3 dBm output power. Hence, this work demonstrates that the class-D topology can be employed in capsule endoscopes to deliver a maximized output power with significant efficiency and extend the battery life while the capsule advances in the gastrointestinal tract.