Battery-less 2 mm cube audio node concept powered by inductive/RF harvesting, with MEMS microphone capture, RF SoC burst transmission, rectification, and ceramic buffer storage.

3.3 V acoustic sensor analog front-end using ZTS6216 MEMS microphone and TLV9062 gain/filter stages, tuned for 2.5 kHz response with ADC-ready output, test points, analog grounding, and manufacturable PCB rules.

ESP32-S3 CAM Audio-Visual Controller with I2S MEMS Microphone, Class-D Amplifier, SPI Display, Servos, Capacitive Touch and Integrated USB-C Power-Only Sink (VBUS via J6 -> 5V_IN -> SW1:P1 -> 5V_SW, CC1/CC2 5.1 kOhm to GND, VBUS TVS Surge Protection) + Added optional bulk electrolytic caps on 5V_SW near servo headers

ESP32-S3 CAM Audio-Visual Controller with I2S MEMS Microphone, Class-D Amplifier, SPI Display, Servos, Capacitive Touch and Integrated USB-C Power-Only Sink (VBUS via J6 → 5V_IN → SW1:P1 → 5V_SW, CC1/CC2 5.1 kΩ to GND, VBUS TVS Surge Protection) #USB_C #PowerManagement #5V

ESP32-S3 Audio Logger with Real-time Ambient Capture using I2S MEMS Microphone