Texas Instruments UCC2891 - Manual (Page 10)

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7 Power Up/Down Test Procedures
81
79
87
83
91
89
93
85
2 6 18 26 22 10 14
I
OUT
- Output Current - A
V
IN
= 36 V
V
IN
= 72 V
V
IN
= 48 V
P
e
rc
e
n
t
E
ff
ic
ie
n
c
y
-
%
V
OUT
= 3.3 V
f
S
= 300 kHz
OVERALL EFFICIENCY
vs
OUTPUT CURRENT
10
-40
-60
100 1 k 10 k 100 k
0
-20
40
20
60
-120
-180
0
-60
120
60
180
V
IN
= 36 V
I
OUT
= 10 A
g
M
= -8 dB
F
M
= 50°
Gain
Phase
f - Frequency - Hz
G
a
in
-
d
B
P
h
a
s
e
-
°
GAIN AND PHASE
vs
FREQUENCY
4
2
10
6
12
8
6 18 26 30 22 10 14 2
I
OUT
- Output Current - A
V
IN
= 36 V
V
IN
= 72 V
V
IN
= 48 V
P
L
O
S
S
-
P
o
w
e
r
L
o
s
s
-
W
V
OUT
= 3.3 V
f
S
= 300 kHz
POWER LOSS
vs
OUTPUT CURRENT
Power Up/Down Test Procedures
Figure 3.
Figure 5.
Figure 4.
Using the UCC2891 Active Clamp Current Mode PWM Controller 10 SLUU178A – November 2003 – Revised December 2006
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