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I have a 5V solenoid, and I am trying to power it from littleBits.

I had a littleBits servo bit and cut its wires. The orange wire should be control wire. The reason I want littleBits is because I am using its noise sensitivity bit, which did activate the servo.

I also have a Mosfet switch https://www.amazon.com/dp/B07NWD8W26

In the switch I put a 5V 1A USB power.

The LED on the switch does go on, but nothing moves on solenoid.

I have tried many combinations of wires.

Any ideas how to start debugging?

enter image description here

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    \$\begingroup\$ Well VIN- isn’t connected. Remember, current flows in a loop. No loop, no work. I can’t see any 0V connection from littlebits either. I think we’ll need a schematic or a least a sketch of how you’ve connected everything. \$\endgroup\$
    – Kartman
    Commented Dec 25, 2021 at 7:35
  • \$\begingroup\$ (1) You might like to skim the answers to the following EESE Q&A using a similar MOS switch modu;e: electronics.stackexchange.com/questions/481578/… \$\endgroup\$
    – tlfong01
    Commented Dec 25, 2021 at 7:37
  • \$\begingroup\$ (2) You might like to read the schematic in my to complete answer below. \$\endgroup\$
    – tlfong01
    Commented Dec 25, 2021 at 7:47
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    \$\begingroup\$ Connected white usb ground to vin out. And tried both red and brown as ground for control wire. Also tried red and brown as control wire with grounds. Nothing \$\endgroup\$
    – hunterp
    Commented Dec 25, 2021 at 8:41
  • \$\begingroup\$ @hunterp - Hi, I have converted your shortened Amazon affiliate link into a plain link (which Stack Exchange may convert into their own affiliate link). Please don't do anything which could be considered as planting affiliate links, including those obscured behind a shortened URL, to avoid your posts potentially being treated as spam. Thanks. \$\endgroup\$
    – SamGibson ♦
    Commented Dec 26, 2021 at 7:45

1 Answer 1

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Question

Can I drive this solenoid with a USB 5V power supply?

solenoid

Answer

(1) Your XY-MOS module is a dual N-Channel Power MOSFET switch which can be used as a simple current switch, for a relay, solenoid, or a lamp etc, controlled by a DC voltage level control signal.

If, instead of a simple DC level signal, you use a PWM signal, you are switching on and off at a frequency, so controlling the brightness of a lamp, or speed of a a DC motor.

(2) This is a schematic of the MOS switch module:

mos switch

(3) A solenoid can be used to switch on/off a water valve, or as a door lock. A relay can be used to switch on/off a motor or the brightness of a lamp. Their input is sort of a inductive coil. You can read the following schematic to get a rough idea of the control signals.

mos switch

(4) So for a solenoid to turn on/off a water valve, you don't need any PWM signal, you only use a DC voltage level. The simplified schematic is shown below.

solenoid schematic

(5) Troubleshooting notes

In you experiment, if the status LED is on, the two MOSFET switches should most likely be on, switching the 12V power to the solenoid. But:

(a) Are are you sure it is a 5V solenoid, not a 12V one?

(b) If a DC 9V battery to used to control the LitteBit's 9g toy servo, which needs 100-250mA typical current during movement https://www.youtube.com/watch?v=5yHcMRPP0Ys, it might not be able to switch on a more powerful 5V/12V solenoid water valve, which usually requires more than 350mA.

(c) One way to verify if your battery is too weak to drive the solenoid which might need 300+ mA, you can replace the solenoid by a 3V~6V toy DC motor, which needs only around 60mA to start steadily moving.

(d) Point to point soldering for reliable electrical contacts.

(e) Short/Connect all signal grounds together.

mos switch

/ to continue, ...

References

(1) Medium Push-Pull Solenoid - 5V (800mA) or 6V (1A)- AdaFruit US$7.5

(2) Why Your Solenoid Needs a Diode? - Collin’s Lab Notes 2021may20

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    \$\begingroup\$ Solenoid: adafruit.com/product/3992 And im using 5V 1A usb in vin \$\endgroup\$
    – hunterp
    Commented Dec 25, 2021 at 19:20
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    \$\begingroup\$ Also connected usb power directly to solenoid...nothing. \$\endgroup\$
    – hunterp
    Commented Dec 26, 2021 at 5:08
  • \$\begingroup\$ Well, your big solenoid takes 800mA, but you small USB can only give 500mA. \$\endgroup\$
    – tlfong01
    Commented Dec 26, 2021 at 5:30
  • \$\begingroup\$ One more thing: You need a "fly back" diode for your solenoid. See Ref 2. \$\endgroup\$
    – tlfong01
    Commented Dec 26, 2021 at 6:11
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    \$\begingroup\$ @tlfong01 your drawings of XY-MOS schematics are wrong. With a multimeter you can find that IN+ and OUT+ of XY-MOS are in direct contact. It means that the gates are not on the input lane, as you have drawn, but on the ground lane. This can be important for some applications and can confuse the readers of your answer. Please correct it. \$\endgroup\$
    – Dmitry Mikushin
    Commented Sep 5, 2023 at 19:05

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