AAT1407 Advanced Analogic Technologies, Inc., AAT1407 Datasheet - Page 14

• Manufacturer Part Number: AAT1407
• Description: 6 Channel Led Backlight Driver With Integrated Boost And High Frequency Direct Pwm Dimming
• Manufacturer: Advanced Analogic Technologies, Inc.

The right half plane (RHP) zero can be calculated by:
It is recommended to design the bandwidth to one
decade lower than the frequency of RHP zero to guaran-
tee the loop stability. A series capacitor and resistor
network (R1 and C3) connected to the COMP pin sets the
pole and zero which are given by:
14
SwitchReg
TM
6 Channel LED Backlight Driver with Integrated Boost and High Frequency Direct PWM Dimming
f
Z_ESR
f
P_COM
f
Z_COM
=
2π · L
=
VIN
=
2π · R
2π · R
1
· I
V
1
1
IN
OUT
EA
1
2
· C
Figure 3: AAT1407 Equivalent Output Stage.
· C
· V
3
3
L1
OUT
w w w . a n a l o g i c t e c h . c o m
Where:
C
R
R
(2.97MΩ).
A 15nF (C3) capacitor and a 5kΩ (R1) resistor in series
are chosen for optimum phase margin and fast transient
response.
3
1
EA
is the compensation resistor
is the compensation capacitor
D1
is the output resistance of the error amplifier
ESR
C4
VOUT
R
PRODUCT DATASHEET
O
I
OUT
AAT1407
1407.2010.06.1.0