Due + TPL7407L, outputs flashes on startup and shutdown.

I have made a board with a Due (Core) and 4 TPL7407L low side drivers to drive relays and LEDs in buttons on my project car.

I have got everyting programmed and working flawless, the only annoying problem I have now, is that all the things driver by the relays (wiper, washer pump, headlights, turn signals, horn etc.) and all the lights in the switches flash on for about 0,5 seconds when I turn on or off the ignition.

I have GND and battery 12v connected to the TPL7407 drivers, and the arduino is turned on and off by the ignition.
The TPL7407 drivers needs a high input to turn the outputs on.

Is there any way to stop the outputs from going high during startup and shutdown of the arduino?

I found this in a separate forum thread, I will try this now.

"When Arduino starts up (before entering setup), the pin is set as INPUT (floating, high impedance). In this state, the voltage level at the pin could easily drift to a level that turns on the MOSFET. To prevent this, all you need to do is install a pull-down resistor from pin 10 to GND. A good value would be 10K."

Resistors did not help :frowning:

any ideas?

The fix posted in reply #1 works after a Reset. If that doesn't work for you, I suspect an issue with the code.

Post a minimal sketch that reproduces the issue you are encountering.