AAT1168-Q5-T AAT [Advanced Analog Technology, Inc.], AAT1168-Q5-T Datasheet - Page 16

• Manufacturer Part Number: AAT1168-Q5-T
• Description: TRIPLE-CHANNEL TFT LCD POWER SOLUTION WITH OPERATIONAL AMPLIFIERS
• Manufacturer: AAT [Advanced Analog Technology, Inc.]

ESR: Equivalent Series Resistance
Example 2:
Boost Converter Power loss
The largest portions of power loss in the boost
converter are the internal power MOSFET, the inductor,
the Schottky diode, and the output capacitor. If the
boost
approximately 3.3% power loss in the internal MOSFET,
1% power loss in the inductor, 5.1% power loss in the
Schottky diode, and 0.6% power loss in the output
capacitor.
Loop Compensation Design
The voltage-loop gain with current loop closed sets the
stability of steady state response and dynamic
performance
compensation design is as follows:
P
P
V
V
V
Figure 4. Closed-current Loop for Boost with PCM
ESR
ESR
RIPPLE
RIPPLE
RIPPLE
= 0.023W or 0.6% power loss
= I
converter
(
(
(
= 26mV
C
Lpeak
ESR
OUT
C
OUT
)
)
)
of
2
= 22mV
= 4mV
.r
= 38µF,
C
has
transient
Advanced Analog Technology, Inc
90%
r
C
= 20m
response.
efficiency,
–
The
Advanced Analog Technology, Inc . –
–
there
台 灣 類 比 科 技 股 份 有 限 公 司
loop
Page 16 of 22
Version 1.00
is
Figure 5. Block Diagram of Boost Converter with
Peak Current Mode (PCM)
Power Stage Transfer Functions
The duty to output voltage transfer function
Where
And
capacitor ESR,
is output filter capacitor,
resistance, and
The duty to inductor current transfer function
Where
r
r is the inductor equivalent series resistance,
T (s)
w
T
L
p
pi
z
(
2
r
C[r R
2 LC R
) s
L
T
R
V
Dr
p0
T
d
i
d
O
L
L
l
pi0
–
DS
1
L
r
C
T
T
V
L
D
p0
pi
O
V
r
1 (
C
0
O
L R
2
(s w
AAT1168/1168A/1168B
1 D R
R r 1 D ] L
R is the diode forward resistance.
R is the converter load resistance, C
s
s
.
[r
L c
2
R
2
F
D
L
L
r
L
R )
,
2 w s w
1 D R ]
2
esr
w
F
s
r
r
2r
C
C
n
L
w
C
)(s w
n
w
n
2
2
r
s
r
,
DS
C
zi
w
1 D R
LC R
L
zi
w
,
n
z2
is the transistor turn on
w
2
,
n
)
esr
2
C R / 2 r
2
L
L
r
L
C
Cr
1
1
r
C
C
T
T is:
p
May 2008
pi
is :
r
C
is