Dear Sir or Madame, We are currently developing an application where the current consumption is very limited. We are using a "STM32L4S5VIT" Especially at the beginning( Boot process) the current consumption is very high.

What is the problem during your programm setup? High current or energy (current * time for setup) ? In the first case, switch to a lower frequency early in the setup. This will run longer, but with less current.

Identify where the peak consumption is occuring, ie have waypoints where you signal via GPIOs and plot that against the current consumption, that way you'll have a profile from which areas to focus on.

Initial clock sources

Starting different clock sources

Waiting for sources and PLLs to lock

Initializing, clearing and copying statics

> Especially at the beginning( Boot process) the current consumption is very high.

This is a relative statement.

How high is the current/power consumption, and what do you expect to see ?

Have you checked the datasheet ?

It specifies average currents for many operation modes, clock frequencies and environment temperatures.