L6911E

Device description

23/34

Note:

To understand the reason of the previous assumption, the scheme in Figure 11 on page 23

must be considered.

In this scheme, the inductor current has been substituted by the load current, because in the

frequencies range of interest for the Droop function these current are substantially the same

and it was supposed that the droop network don't represent a charge for the inductor.

Figure 11. Voltage regulation with droop function block scheme

It results:

Equation 23

Because in the interested range |Gloop|>>1.

To obtain a flat shape, the relationship considered will naturally follow.

Av(s)

R(s)

Vout

V com p

Iout

d

s

L

s

OUT

R

τ

τ

⋅

+

⋅

+

⋅

1

1

Z

OUT

V

o

I

LOAD

---------------

R

d

1s

τ

L

+

1s

τ

d

+

------------------

G

LOOP

1G

LOOP

+

----------------------------

⋅⋅

R

OUT

1s

τ

L

+

1s

τ

d

+

------------------

⋅

==

=