Circuit Documentation

Summary

This document provides a detailed overview of a circuit that includes an ESP32 Devkit V1 microcontroller, an INMP441 microphone, a Max98357 amplifier, a loudspeaker, pushbutton, and two LEDs (red and blue). The circuit is designed to capture audio input, process it, and output it through a loudspeaker, with additional user interaction via a pushbutton and visual feedback through LEDs.

Component List

1. INMP441 FRONT MIC

   • Description: Digital MEMS microphone
   • Pins: L/R, WS, SCK, SD, VDD, GND

2. Pushbutton

   • Description: Simple pushbutton switch
   • Pins: Pin 3 (out), Pin 4 (out), Pin 1 (in), Pin 2 (in)

3. LED: Two Pin (red)

   • Description: Red LED
   • Pins: cathode, anode

4. LED: Two Pin (blue)

   • Description: Blue LED
   • Pins: cathode, anode

5. ESP32 Devkit V1

   • Description: Microcontroller with Wi-Fi and Bluetooth capabilities
   • Pins: 3V3, GND, D15, D2, D4, RX2, TX2, D5, D18, D19, D21, RX0, TX0, D22, D23, EN, VP, VN, D34, D35, D32, D33, D25, D26, D27, D14, D12, D13, VIN

6. Loudspeaker

   • Description: Audio output device
   • Pins: pin1, pin2

7. Max98357

   • Description: Class D amplifier
   • Pins: LRC, BLCK, DIN, GAIN, SD, GND, VIN, -, +

Wiring Details

INMP441 FRONT MIC

• VDD connected to Pushbutton Pin 4 (out)
• VDD connected to Max98357 VIN
• VDD connected to ESP32 Devkit V1 3V3
• L/R connected to INMP441 FRONT MIC GND
• L/R connected to ESP32 Devkit V1 GND
• WS connected to ESP32 Devkit V1 D15
• SCK connected to ESP32 Devkit V1 D2
• SD connected to ESP32 Devkit V1 D4

Pushbutton

• Pin 4 (out) connected to INMP441 FRONT MIC VDD
• Pin 4 (out) connected to Max98357 VIN
• Pin 4 (out) connected to ESP32 Devkit V1 3V3
• Pin 3 (out) connected to ESP32 Devkit V1 D33

LED: Two Pin (red)

• cathode connected to ESP32 Devkit V1 D25
• anode connected to Max98357 GAIN
• anode connected to Max98357 GND

LED: Two Pin (blue)

• cathode connected to ESP32 Devkit V1 D32
• anode connected to Max98357 GAIN
• anode connected to Max98357 GND

ESP32 Devkit V1

• 3V3 connected to Pushbutton Pin 4 (out)
• 3V3 connected to INMP441 FRONT MIC VDD
• 3V3 connected to Max98357 VIN
• GND connected to INMP441 FRONT MIC L/R
• GND connected to INMP441 FRONT MIC GND
• D15 connected to INMP441 FRONT MIC WS
• D2 connected to INMP441 FRONT MIC SCK
• D4 connected to INMP441 FRONT MIC SD
• D32 connected to LED: Two Pin (blue) cathode
• D33 connected to Pushbutton Pin 3 (out)
• D25 connected to LED: Two Pin (red) cathode
• D26 connected to Max98357 DIN
• D27 connected to Max98357 BLCK
• D14 connected to Max98357 LRC

Loudspeaker

• pin1 connected to Max98357 -
• pin2 connected to Max98357 +

Max98357

• VIN connected to Pushbutton Pin 4 (out)
• VIN connected to INMP441 FRONT MIC VDD
• VIN connected to ESP32 Devkit V1 3V3
• DIN connected to ESP32 Devkit V1 D26
• BLCK connected to ESP32 Devkit V1 D27
• LRC connected to ESP32 Devkit V1 D14
• - connected to Loudspeaker pin1
• + connected to Loudspeaker pin2
• GAIN connected to LED: Two Pin (blue) anode
• GAIN connected to LED: Two Pin (red) anode
• GND connected to LED: Two Pin (blue) anode
• GND connected to LED: Two Pin (red) anode

Documented Code

ESP32 Devkit V1 Code

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

INMP441 FRONT MIC Code

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

This documentation provides a comprehensive overview of the circuit, including the components used, their connections, and the code running on the microcontrollers.