Datasheet

VOUT
R
ESR
C
O
R
L
VC
gm
ps
VOUT
R
ESR
C
O
R
L
VC
gm
ps
fp
fz
Adc
s
1+
2 z
VOUT
= Adc
VC
s
1+
2 p
æ ö
ç ÷
´ ¦
è ø
´
æ ö
ç ÷
´ ¦
è ø
p
p
ps L
Adc = gm R´
O L
1
p =
C R 2
¦
´ ´ p
O ESR
1
z =
C R 2
¦
´ ´ p
TPS54620
www.ti.com SLVS949C –MAY 2009– REVISED MAY 2011
Figure 31. Simplified Small Signal Model for Peak Current Mode Control
Figure 32. Simplified Frequency Response for Peak Current Mode Control
(10)
(11)
(12)
(13)
Where
gm
ea
is the GM amplifier gain ( 1300μA/V)
gm
ps
is the power stage gain (16A/V).
R
L
is the load resistance
C
O
is the output capacitance.
R
ESR
is the equivalent series resistance of the output capacitor.
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