I have a MAX809 with RESET pin connected to the gate of IRLML6344. I will rephrase my question.

At 5 V, RESET is also 5 V and the LED lights up. But if I add the fan, RESET drops to 0 V and draws 140 mA. Adding a 100 nF cap solved this problem. What is happening here?

Then I added a MOSFET to the circuit but depending on what is connected to LOAD2, RESET triggers at different values. I tried with 0.1 µF, 1 µF, and 10 µF. But RST triggers outside the specs. (specs is RESET off at 2.80 V and RESET is on at 2.93 V)

Using 100 µF at C2,

RESET is low at 2.80 V and high at 2.93 V when load is only an LED.

RESET is low at 2.86 V and high at 2.93 V when load are LED and a DC fan with 150 mA current draw.

RESET is low at 2.9 V and high at 3.2 V when I added a buck converter (LM2596) with nothing connected to it.

For context, this is what I planned to do.

posted about 4 years ago

CC BY-SA 4.0

4y ago

timelyfiasco‭

9 reputation 2 1 1 9