Smart Sleep Alarm Mask

This smart sleep alarm mask uses ambient light sensing to detect when morning arrives and gently wakes the user with gradually increasing light and vibration. Built around an Arduino Uno, the mask combines a proximity sensor and ambient light sensor to monitor sleep conditions, triggering a red LED that brightens over time while a coin motor provides gentle haptic feedback.

This guide provides a complete parts list, wiring diagram, and step-by-step assembly instructions for building the prototype on a breadboard. Firmware code handles sensor input and output control, with detailed comments explaining how the light and vibration outputs are managed to create a natural wake experience.

Wiring diagram

Loading diagram…

Gather all the parts

Qty	Component
1	Adafruit VCNL4040 Adafruit VCNL4040
1	Adafruit VEML7700 Adafruit VEML7700
1	Adafruit MAX98357A Adafruit MAX98357A
1	8 ohm flat speaker 8 ohm flat speaker
1	8 ohm flat speaker 8 ohm flat speaker
1	Protected 500 mAh 1S LiPo Protected 500 mAh 1S LiPo
1	AO3400A MOSFET AO3400A MOSFET
1	100 ohm gate resistor 100 ohm gate resistor
1	100 kohm gate pulldown 100 kohm gate pulldown
1	red diffused LED red diffused LED
1	2.2 kohm LED resistor 2.2 kohm LED resistor
1	red diffused LED red diffused LED
1	2.2 kohm LED resistor 2.2 kohm LED resistor
1	AO3400A MOSFET AO3400A MOSFET
1	100 ohm gate resistor 100 ohm gate resistor
1	100 kohm gate pulldown 100 kohm gate pulldown
1	amber diffused LED amber diffused LED
1	2.2 kohm LED resistor 2.2 kohm LED resistor
1	amber diffused LED amber diffused LED
1	2.2 kohm LED resistor 2.2 kohm LED resistor
1	3 V 10 mm coin motor 3 V 10 mm coin motor
1	AO3400A motor MOSFET AO3400A motor MOSFET
1	100 ohm gate resistor 100 ohm gate resistor
1	100 kohm gate pulldown 100 kohm gate pulldown
1	1N5819 flyback diode 1N5819 flyback diode
1	10 ohm motor series resistor 10 ohm motor series resistor
1	Momentary snooze button Momentary snooze button
1	470 uF 6.3 V capacitor 470 uF 6.3 V capacitor

Assemble it in 6 steps

1. Keep this prototype on the bench

Do not wear or charge the assembled mask until firmware and current measurements have been validated. The current firmware is bring-up only.

Never charge while wearing. This is not a fire safety device.

2. Connect the two light sensors

Connect both sensors to 3.3 V and ground. Connect SDA to D4 for data and SCL to D5 for the clock. Put the proximity board inside the cup and the ambient-light board facing the room.

3. Assemble the limited-current lights

Each LED has its own 2.2 kohm resistor from 3.3 V to its anode. Connect its cathode to its color MOSFET drain. Connect MOSFET sources to ground, gates through 100 ohms to D0 for red or D1 for amber, and each gate through 100 kohms to ground.

4. Connect the motor driver

Connect 3.3 V through the 10 ohm resistor to motor positive. Connect motor negative to the MOSFET drain and source to ground. D2 drives the gate through 100 ohms, with 100 kohms from gate to ground. Connect the diode stripe to motor positive and its other end to motor negative. Verify regulator headroom and motor starting before use.

5. Connect mono speakers in series

Connect amplifier OUT+ to speaker 1 positive, speaker 1 negative to speaker 2 positive, and speaker 2 negative to OUT-. Neither output goes to ground. Connect BCLK to D8, LRC to D9, DIN to D10 and shutdown to D7. Connect VIN to battery positive and GND to common ground. Put the capacitor across this supply with correct polarity.

Test away from ears at minimum volume first.

6. Connect button and battery last

Connect the button between D3 and ground. Check all wiring for shorts. Connect protected battery positive to the underside BAT+ pad and negative to BAT-. Insulate all joints and provide strain relief.

Never solder directly to a pouch cell. Do not compress or puncture it.

Review all connections

1. Connections between "prox" and "Arduino"

Function	prox	Arduino
`power`	VIN	3V3
`ground`	GND	GND
`data`	SDA	GPIO 4
`data`	SCL	GPIO 5

2. Connections between "lux" and "Arduino"

Function	lux	Arduino
`power`	VIN	3V3
`ground`	GND	GND
`data`	SDA	GPIO 4
`data`	SCL	GPIO 5

3. Connections between "amp" and "Arduino"

Function	amp	Arduino
`power`	VIN	3.7V
`ground`	GND	GND
`data`	BCLK	GPIO 8
`data`	LRC	GPIO 9
`data`	DIN	GPIO 10
`data`	SD	GPIO 7
`data`	OUT+ → 8 ohm flat speaker +	EXT

4. Connections between "spk1" and "Arduino"

Function	spk1	Arduino
`data`	- → 8 ohm flat speaker +	EXT

5. Connections between "spk2" and "Arduino"

Function	spk2	Arduino
`data`	- → Adafruit MAX98357A OUT-	EXT

6. Connections between "battery" and "Arduino"

Function	battery	Arduino
`power`	+	3.7V
`ground`	-	GND
`data`	+ → XIAO BAT+ underside pad	EXT
`data`	- → XIAO BAT- underside pad	EXT

7. Connections between "redg" and "Arduino"

Function	redg	Arduino
`data`	1	GPIO 0
`data`	2 → AO3400A MOSFET G	EXT

8. Connections between "redpd" and "Arduino"

Function	redpd	Arduino
`data`	1 → AO3400A MOSFET G	EXT
`ground`	2	GND

9. Connections between "redq" and "Arduino"

Function	redq	Arduino
`ground`	S	GND

10. Connections between "red0r" and "Arduino"

Function	red0r	Arduino
`power`	1	3V3
`data`	2 → red diffused LED A	EXT

11. Connections between "red0" and "Arduino"

Function	red0	Arduino
`data`	K → AO3400A MOSFET D	EXT

12. Connections between "red1r" and "Arduino"

Function	red1r	Arduino
`power`	1	3V3
`data`	2 → red diffused LED A	EXT

13. Connections between "red1" and "Arduino"

Function	red1	Arduino
`data`	K → AO3400A MOSFET D	EXT

14. Connections between "amberg" and "Arduino"

Function	amberg	Arduino
`data`	1	GPIO 1
`data`	2 → AO3400A MOSFET G	EXT

15. Connections between "amberpd" and "Arduino"

Function	amberpd	Arduino
`data`	1 → AO3400A MOSFET G	EXT
`ground`	2	GND

16. Connections between "amberq" and "Arduino"

Function	amberq	Arduino
`ground`	S	GND

17. Connections between "amber0r" and "Arduino"

Function	amber0r	Arduino
`power`	1	3V3
`data`	2 → amber diffused LED A	EXT

18. Connections between "amber0" and "Arduino"

Function	amber0	Arduino
`data`	K → AO3400A MOSFET D	EXT

19. Connections between "amber1r" and "Arduino"

Function	amber1r	Arduino
`power`	1	3V3
`data`	2 → amber diffused LED A	EXT

20. Connections between "amber1" and "Arduino"

Function	amber1	Arduino
`data`	K → AO3400A MOSFET D	EXT

21. Connections between "mg" and "Arduino"

Function	mg	Arduino
`data`	1	GPIO 2
`data`	2 → AO3400A motor MOSFET G	EXT

22. Connections between "mpd" and "Arduino"

Function	mpd	Arduino
`data`	1 → AO3400A motor MOSFET G	EXT
`ground`	2	GND

23. Connections between "mq" and "Arduino"

Function	mq	Arduino
`ground`	S	GND

24. Connections between "mr" and "Arduino"

Function	mr	Arduino
`power`	1	3V3
`data`	2 → 3 V 10 mm coin motor +	EXT

25. Connections between "motor" and "Arduino"

Function	motor	Arduino
`data`	- → AO3400A motor MOSFET D	EXT

26. Connections between "diode" and "Arduino"

Function	diode	Arduino
`data`	A → 3 V 10 mm coin motor -	EXT
`data`	K → 3 V 10 mm coin motor +	EXT

27. Connections between "button" and "Arduino"

Function	button	Arduino
`data`	1	GPIO 3
`ground`	2	GND

28. Connections between "cap" and "Arduino"

Function	cap	Arduino
`power`	+	3.7V
`ground`	-	GND

Deploy the firmware

main.cppOpen in Schematik

#include <Arduino.h>
// Bring-up only: outputs remain off until the full application is validated.
void setup() {
  for (int p : {0,1,2,7}) { pinMode(p, OUTPUT); digitalWrite(p, LOW); }
  pinMode(3, INPUT_PULLUP);
}
void loop() { delay(100); }