AN1606 APPLICATION NOTE

14/18

Boost Inductor design.

The boost inductor has been design as been previously described .

For the 600W application, the nominal current ripple has been set around 22%, gives requires the inductance

value L=440

µH.

The inductor requirements can be met using the core set type E55/28/21, characterized with the following key

parameters:

A = 357mm^2;

lcore = 123mm;

m_core =>1600;

Vcore = 43.7mm^3

Using the relation g), Vcore>38.8mm^3

The result confirms that the core is good enough.

Using the relation h), the resulting N=42.

For the 600W, the coil has been realized with 21 turns +21 turns.

For minimize the high frequency losses, the "multiple wire" solution has been used.

Imposing the copper losses (Pcu = 3.8W), it has been used 14 wires having a diameter d = 0.4 mm each.

Output Capacitor.

the 800W application is still good for the 600W application.

Power Devices.

For the two boost diodes, as for the 800W application, the STTH8R06FP has been used.

Concerning the Powermos, the devices used in the 600W version application are two STW26NM50F.