Boost converter reloading

Hello. I have a problem with boost converter.

It has enable pin and work in 2 modes : Bypass switch(If enable pin = Low) and boost converter ( Enable pin = High)

When I connected Enable pin to atmega and set it High, it looks like boost converter is reloading all the time, because LED is blinking very fast.

void setup() {
  pinMode(5, OUTPUT);
  pinMode(0, OUTPUT);
}

void loop() {
  
    digitalWrite(5, HIGH); // Turns ON boost converter
                      
    digitalWrite(0, HIGH);    // turn the LED ON
   
}

When I connected Enable pin to battery VCC everything is all right.

What is the differenfe between atmega and battery voltage?
I think that output from atmega pin5 is not constant and that causes reload?

I just found out that On pin 5 I have only 0.5 voltage, why it is so small?

Voltage was fine, I did bad measurement. I fixed problem by adding resistor between Enable pin and atmega 5 pin