Table 1 Input inventory for smartwatch life-cycle assessment.

From: Life cycle assessment (LCA) of circular consumer electronics based on IC recycling and emerging PCB assembly materials

Component

Quantity

Details

Printed Wiring Board 2-layer

7.07 cm2

Standard PCB

Capacitor ceramic MLCC 0603

80

Representative for all capacitors

Resistor flat chip 0402

462

Representative for all resistors

Solder paste SnAg3Cu0.5

3 g

 

OLED screen

7.3 cm2

Self-made (see supplementary)

Cell BR series (Li/poly-carbon monofluoride)

6 g

Battery substitute

LED SMD high-efficiency with lens

1

 

Plastic extrusion profile

18 g

Case and strap substitute

IC BGA 48 (72 mg) 8 × 6 mm MPU

1

Main processor substitute

Filter SAW (25 mg) 3 × 7 × 1

3

RxD frontend component

IC DFN 10 (22.3 mg) 3 × 3 mm CMOS

1

RxD frontend component

Transistor signal SOT-883

1

Infineon switch substitute

IC BGA 48 (70 mg) 6 × 6 × 1.1 mm

1

Power amplifier substitute

IC WLP CSP 49 (10.2 mg) MPU generic

1

RF chip substitute

IC BGA 144 (181 mg) 10 × 10 mm

0.01

Power tracker substitute

IC WLP CSP 49 (10.2 mg) CMOS logic

8

Co-processor substitute

Soldering electricity

0.533 kWh

 

Use-phase electricity

3.86 kWh

Assumes battery fully recharged every day for 3 years