The +5VSB Power Supply
The +5VSB (a.k.a. standby) power supply is independent of the main power supply, since it is on all the time.
On the Fractal Design Newton R3 800 W, the +5VSB power supply has an integrated circuit that incorporates the PWM controller and the switching transistor in a single chip. However, the manufacturer scratched the markings on this chip, making it impossible for us to identify it.
The rectification of the +5VSB output is performed by an MBR2060CT Schottky rectifier, which supports up to 20 A (10 A per internal diode at 135º C, 0.95 V maximum voltage drop).