Using DC-DC-step-up and DC-DC-step-down converters

360modena_cs:
I have a battery 6V DC with which I want to supply my Arduino (through USB) + the rest of the circuit which operates with 5 Volts.

I thought of using a DC-DC-step-down converter, but I didn't find something that gets 6 Volt on input and outputs 5 Volt.

They need more than 6 Volt on their input. So, I thought of using a DC-DC-step-up converter to take the input from 6 Volt and boost it to 9 Volt, and then a DC-DC-step-down converter that will take the input of 9 Volt and output 5 Volt.

Can this happen? Or will I have problems with the current? The circuit + Arduino will use maximum 1 Amperes.

Which Arduino, what circuits.

The Pololu 5volt/1Amp buck converter has a very low dropout voltage (< 0.5volt@600mA).
Other types have a higher dropout voltage.

Can't power through USB then.
The (unknown) Arduino might have a 500mA fuse or 500mA diode in the USB supply line.
Leo..