I have built up a 6 solenoid version, but having difficulty in getting the correct voltages.I have 12v and 5.7v in the correct rails for the solenoids and into the Arduino. However when the program runs I am only getting 0.4v at pin B of each tip120…..
Should the Arduino light when the usb is connected and no power switched on to the power supply on the board?
The program seems to trigger each Tip120 ok as I have LED’s that light in the correct sequence, albeit faint due to low voltage.
My Standby and active LEDS have 2.2v across them when active.
My Solenoids are not triggering i feel due to the low voltage across the TIP.
Note: I have just noticed that the small blue LED on the step down power supply is also lit when only the USB cable is connected and power is switched off to the board.