I have completed a similar project for a farmer a few years ago. Here my notes from that project.
To interface an SMC solenoid valve (e.g., VDW Series) with a Raspberry Pi Pico for on/off control, follow these steps:
Circuit Design
Power Requirements:
The SMC VDW Series typically operates at 12V or 24V DC (confirm voltage from valve specifications). The Pico’s GPIO pins output 3.3V, so a MOSFET or relay is required to handle higher voltages.
Key Components:
Logic-Level N-Channel MOSFET (e.g., IRLB8743) or relay module.
Flyback Diode (1N4007) to protect against voltage spikes.
External Power Supply (matching the solenoid’s voltage, e.g., 12V).
Resistor (1kΩ) between Pico GPIO and MOSFET gate.
Wiring:
Connect the Pico’s GPIO pin (e.g., GP14) to the MOSFET’s gate via the resistor.
Connect the MOSFET’s source to ground.
Connect the solenoid’s positive terminal to the external power supply and negative terminal to the MOSFET’s drain.
Place the flyback diode across the solenoid terminals (reverse-biased).
Key Considerations
MOSFET Selection: Ensure the MOSFET’s gate threshold voltage is compatible with the Pico’s 3.3V output (logic-level MOSFETs work best).
Power Isolation: Use a separate power supply for the solenoid to avoid overloading the Pico’s 5V rail.
Protection:
Flyback Diode: Prevents voltage spikes from damaging the MOSFET.
Capacitor: Add a 47µF capacitor across the power rails to stabilize voltage.
Troubleshooting
If the solenoid doesn’t activate:
Verify MOSFET connections (gate, drain, source).
Check external power supply voltage/current.
Test the GPIO pin with an LED to confirm output functionality.
This setup allows safe control of the SMC solenoid valve using the Pico’s low-voltage GPIO pins while handling higher power requirements externally
To interface an SMC solenoid valve (e.g., VDW Series) with a Raspberry Pi Pico for on/off control, follow these steps:
Circuit Design
Power Requirements:
The SMC VDW Series typically operates at 12V or 24V DC (confirm voltage from valve specifications). The Pico’s GPIO pins output 3.3V, so a MOSFET or relay is required to handle higher voltages.
Key Components:
Logic-Level N-Channel MOSFET (e.g., IRLB8743) or relay module.
Flyback Diode (1N4007) to protect against voltage spikes.
External Power Supply (matching the solenoid’s voltage, e.g., 12V).
Resistor (1kΩ) between Pico GPIO and MOSFET gate.
Wiring:
Connect the Pico’s GPIO pin (e.g., GP14) to the MOSFET’s gate via the resistor.
Connect the MOSFET’s source to ground.
Connect the solenoid’s positive terminal to the external power supply and negative terminal to the MOSFET’s drain.
Place the flyback diode across the solenoid terminals (reverse-biased).
Code Example
python
import time
import board
from digitalio import DigitalInOut, Direction
# Configure solenoid control pin
solenoid = DigitalInOut(board.GP14)
solenoid.direction = Direction.OUTPUT
def activate_solenoid(duration=0.5):
solenoid.value = True # Turn on solenoid
time.sleep(duration)
solenoid.value = False # Turn off solenoid
while True:
activate_solenoid()
time.sleep(2) # Wait 2 seconds between activations
Key Considerations
MOSFET Selection: Ensure the MOSFET’s gate threshold voltage is compatible with the Pico’s 3.3V output (logic-level MOSFETs work best).
Power Isolation: Use a separate power supply for the solenoid to avoid overloading the Pico’s 5V rail.
Protection:
Flyback Diode: Prevents voltage spikes from damaging the MOSFET.
Capacitor: Add a 47µF capacitor across the power rails to stabilize voltage.
Troubleshooting
If the solenoid doesn’t activate:
Verify MOSFET connections (gate, drain, source).
Check external power supply voltage/current.
Test the GPIO pin with an LED to confirm output functionality.
This setup allows safe control of the SMC solenoid valve using the Pico’s low-voltage GPIO pins while handling higher power requirements externally
Statistics: Posted by hoodhlab — Wed Mar 26, 2025 7:38 pm