For this activity, I evaluated the power requirements of two output devices used during the week:
a 16x2 LCD display with an I2C adapter and a 5 mm red LED. A digital multimeter was used to verify
that the devices were receiving the expected operating voltage from the microcontroller circuit.
Devices Tested
- 16x2 LCD Display with I2C Adapter
- 5 mm Red LED
- Arduino Uno R3
- Digital Multimeter
- Operating Characteristics
- 5 mm Red LED
Typical operating values:
- Voltage: approximately 2.0 V
- Current: approximately 10–20 mA
- Power Consumption: approximately 20–40 mW
The LED requires very little power and can be controlled directly from a microcontroller
pin when used with a current-limiting resistor.
16x2 LCD Display with I2C Adapter
Typical operating values:
- Supply Voltage: 5 V
- Current Consumption: approximately 20–30 mA
- Power Consumption: approximately 100–150 mW
The LCD requires more power than a single LED because it operates both the display
electronics and the backlight.
Results
Voltage measurements confirmed that both devices were receiving the expected operating voltage
from the microcontroller circuit. Comparing the two devices showed that the LCD display consumes
several times more power than a single LED, but provides significantly greater functionality by
displaying text and information.
What I Learned
This exercise helped me understand how different output devices place different demands on a circuit.
A simple LED requires very little power and is useful as a status indicator, while an LCD display
consumes more power but provides much more information to the user. Understanding these differences
is important when designing electronic systems, especially battery-powered devices where power
consumption must be considered.