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Member #161476

Member Since: November 9, 2010

Country: United States

  • I created a housing for this in openScad that you can 3d print – It is available on Thingiverse.


  • Would LOVE to see this using the MAX1874 instead of the MAX1555 – Ability to switch to run directly of supplied power when available is great and opens up more options for not relying on LiPO.

  • The datasheet for the MAX1555 makes the options clear here.


    In short, you can definitely trick the MAX1555 into charging at 280ma instead of 100ma, if you understand the potential impact on USB sources and the current they make available.

  • So can we modify to wire the power from the mini-usb into the external charging port? This way we would get 250MA instead of just 100MA off the USB connection?

    I’m using a 5v 1amp power source on the other end of the USB cable, and want to power off that single connection.

  • So I have about 40 of these in my hands now. In reality they measure between 4.8 and 4.9 ohms across the coil.

    My math puts me at a 16 ohm resistor to run continuously.

    Which also seems to be right in practice, as I had a 14 ohm 2 watt resistor that let the device run, and a 20 ohm which would not allow the solenoid to operate.

No public wish lists :(