Low-Power Design and Running from Batteries and Sun

10 Lektionen in dieser Stufe

1. Where the Milliamps Go: Profiling an UNO-Compatible Board
   Identify the consumers on a development board beyond the microcontroller itself. · Lab: Measure total board current and estimate the share of regulator, USB chip and LEDs.
2. Measuring Microamps Without Disturbing the Circuit
   Use meter ranges, burden voltage awareness and a bypass switch to measure sleep currents. · Lab: Build a shunt-and-bypass adapter and measure a sleeping chip without resetting it.
3. Sleep Modes of the ATmega328P
   Compare idle, power-save and power-down modes by what keeps running. · Lab: Enter each sleep mode and tabulate the measured current.
4. Waking Periodically with the Watchdog Timer
   Use the watchdog as a low-power wake-up source for intervals of seconds to minutes. · Lab: Blink briefly every eight seconds and sleep in between at microamp level.
5. Waking on External and Pin-Change Events
   Sleep indefinitely until a button or sensor signal arrives. · Lab: Wake from power-down by button and by a sensor interrupt output.
6. Switching Off the ADC, Brown-Out Detector and Unused Peripherals
   Remove hidden consumers during sleep using power-reduction settings. · Lab: Reduce power-down current step by step and record each saving.
7. Clock Speed, Supply Voltage and the 8 MHz 3.3 V Option
   Trade speed for consumption and operate within the safe voltage and frequency area. · Lab: Run the chip at 8 MHz from two AA cells and compare active current with 16 MHz at 5 V.
8. Power-Gating Sensors and Radios with a MOSFET
   Cut supply to external modules between measurements and handle their start-up time. · Lab: Switch a sensor and radio with a P-channel MOSFET and measure the sleep saving.
9. Estimating Battery Life from a Duty-Cycle Profile
   Compute average current from active and sleep phases and derive runtime. · Lab: Measure your node's phases and calculate life on AA cells and on an 18650 cell.
10. Solar Harvesting: Panel, Charger and Storage Sizing
    Size a small panel and battery for year-round operation and wire a harvesting charger safely. · Lab: Measure panel output in sun and shade and decide whether your node's energy balance is positive.

Abschlussprojekt

A solar-assisted wireless sensor node on a bare ATmega328P that sleeps at microamp level, reports by radio and comes with a documented battery-life calculation.

Teile für diese Stufe

• 1 × ATmega328P microcontroller DIP-28
• 1 × Crystal 8 MHz
• 2 × Ceramic capacitor 22 picofarad
• 6 × Ceramic capacitor 100 nanofarad
• 1 × USBasp-compatible ISP programmer
• 1 × UNO-compatible board
• 1 × USB cable matching the board
• 2 × Solderless breadboard 830 points
• 1 × Jumper wire set male-male
• 1 × Digital multimeter with microamp range
• 1 × Resistor assortment 1/4 W
• 1 × Low-quiescent 3.3 V regulator module
• 2 × nRF24L01 radio module
• 1 × BME280 pressure, humidity and temperature module
• 2 × P-channel MOSFET logic level
• 1 × Battery holder 2xAA with batteries
• 1 × Li-ion cell 18650 protected
• 1 × 18650 battery holder
• 1 × Solar panel 6 V 1 W
• 1 × Solar Li-ion charger module
• 1 × Solar learning kit
• 2 × Schottky diode
• 1 × Tactile push button
• 2 × Electrolytic capacitor 100 microfarad

In jeder Lektion legst du die passenden Teile direkt in den Warenkorb. Arduino-kompatibel →