Datasheet

DocID024346 Rev 1 13/42
LED2001 Application notes
Equation 2
Equation 3
where:
Equation 4
S
n
represents the slope of the sensed inductor current, S
e
the slope of the external ramp
(V
PP
peak-to-peak amplitude) that implements the slope compensation to avoid sub-
harmonic oscillations at duty cycle over 50%.
The sampling effect contribution F
H
(s) is:
Equation 5
where:
Equation 6
and
Equation 7
6.3 Error amplifier compensation network
The LED2001 embeds (see Figure 6) the error amplifier and a pre-defined compensation
network which is effective in stabilizing the system in most application conditions.
ω
Z
1
ESR C
OUT
-------------------------------=
ω
P
1
R
LOAD
C
OUT
------------------------------------- -
m
C
1D()0.5
LC
OUT
f
SW
⋅⋅
---------------------------------------------+=
F
H
s()
1
1
s
ω
n
Q
P
-------------------
s
2
ω
n
2
------++
------------------------------------------ -=
ω
n
π f
SW
=
Q
P
1
π m
C
1D()0.5[]
----------------------------------------------------------=