Circuit Documentation

Summary

This document provides a detailed overview of a circuit that includes a metal detector, a loudspeaker, an audio amplifier, a voltage regulator, a microcontroller, and a power source. The circuit is designed to detect metal objects and produce an audible alert through the loudspeaker.

Component List

1. Loudspeaker

   • Description: Converts electrical signals into sound.
   • Pins: pin1, pin2

2. Metal Detector

   • Description: Detects the presence of metal objects.
   • Pins: VCC, GND, D

3. Seeed Studio nRF52840

   • Description: A microcontroller used for processing and control.
   • Pins: VUSB, GND, 3V3, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, NFC1, NFC2, B-, B+

4. ams1117 3.3

   • Description: A voltage regulator that converts higher voltage to 3.3V.
   • Pins: VIN, OUT, GND

5. 7.4v Battery

   • Description: Provides power to the circuit.
   • Pins: +, -

6. Adafruit PAM8302

   • Description: An audio amplifier used to drive the loudspeaker.
   • Pins: GND, VCC, SD, AIN-, AIN+, VO-, VO+

Wiring Details

Loudspeaker

• pin1 is connected to VO- of Adafruit PAM8302.
• pin2 is connected to VO+ of Adafruit PAM8302.

Metal Detector

• VCC is connected to VIN of ams1117 3.3 and + of 7.4v Battery.
• GND is connected to GND of Seeed Studio nRF52840, GND of Adafruit PAM8302, AIN- of Adafruit PAM8302, and - of 7.4v Battery.
• D is connected to pin 2 of Seeed Studio nRF52840.

Seeed Studio nRF52840

• GND is connected to GND of Metal Detector, GND of Adafruit PAM8302, AIN- of Adafruit PAM8302, and - of 7.4v Battery.
• 3V3 is connected to VCC of Adafruit PAM8302.
• pin 2 is connected to D of Metal Detector.
• pin 3 is connected to AIN+ of Adafruit PAM8302.
• B- is connected to GND of ams1117 3.3.
• B+ is connected to OUT of ams1117 3.3.

ams1117 3.3

• VIN is connected to VCC of Metal Detector and + of 7.4v Battery.
• OUT is connected to B+ of Seeed Studio nRF52840.
• GND is connected to B- of Seeed Studio nRF52840.

7.4v Battery

• + is connected to VIN of ams1117 3.3 and VCC of Metal Detector.
• - is connected to GND of Seeed Studio nRF52840, GND of Adafruit PAM8302, AIN- of Adafruit PAM8302, and GND of Metal Detector.

Adafruit PAM8302

• VO- is connected to pin1 of Loudspeaker.
• VO+ is connected to pin2 of Loudspeaker.
• GND is connected to GND of Seeed Studio nRF52840, GND of Metal Detector, AIN- of Adafruit PAM8302, and - of 7.4v Battery.
• VCC is connected to 3V3 of Seeed Studio nRF52840.
• AIN- is connected to GND of Seeed Studio nRF52840, GND of Metal Detector, GND of Adafruit PAM8302, and - of 7.4v Battery.
• AIN+ is connected to pin 3 of Seeed Studio nRF52840.

Code

No code is provided for this circuit.

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This document provides a comprehensive overview of the circuit, including a summary, component list, wiring details, and code section. The wiring details ensure that each component is correctly connected to form a functional circuit.