LTC1775 LINER [Linear Technology], LTC1775 Datasheet - Page 19

• Manufacturer Part Number: LTC1775
• Description: High Power No RSENSE TM Current Mode Synchronous Step-Down Switching Regulator
• Manufacturer: LINER [Linear Technology]

APPLICATIO S I FOR ATIO
A short circuit to ground will result in a folded back
current of:
with a typical value of R
resulting power dissipated in the bottom MOSFET is:
which is less than under full load conditions.
I
P
SC
BOT
( .
0 013
15
80
15
V
mV
–
V
5
2.2nF
)( . )
C
C1
V
U
1 1
( .
6 2
0.1 F
C
SS
DS(ON)
A
U
10k
) ( . )( .
R
2
2
1
C
220pF
C
1 1 0 013
INTV
C2
(
V
15
OUT
C
C
L1: MAGENTICS 55380-A2, 8 TURNS, 15 GAUGE
and (50 C) = 1.1. The
IN
OUT
CC
: SANYO 30SC22M
V
W
: SANYO 6SP680M
6
Figure 11. 5V/10A Fixed Output from Design Example
)( .
1
2
3
4
5
6
7
8
0 5
H
EXTV
SYNC
V
RUN/SS
FCB
I
SGND
V
TH
OSENSE
PROG
CC
LTC1775
s
)
)
0 37
U
BOOST
INTV
.
6 2
PGND
.
SW
V
BG
TG
TK
CC
IN
A
W
16
15
14
13
12
11
10
9
+
+
C
temperature. C
low output ripple. The output ripple in continuous mode
will be highest at the maximum input voltage and is
approximately:
The complete circuit is shown in Figure 11.
IN
D
CMDSH-3
C
0.1 F
C
4.7 F
B
V
F
VCC
is chosen for an RMS current rating of at least 5A at
O
= ( I
1
R
F
0.33 F
L(MAX)
C
6V TO 22V
B
OUT
V
IN
M1
SUD50N03-10
M2
SUD50N03-10
)(ESR) = (4.3A)(0.013 ) = 56mV
MBRS340
is chosen with an ESR of 0.013 for
D1
6 H
L1
+
1775 F11
C
22 F
30V
+
IN
4
C
680 F
6.3V
OUT
V
5V
10A
OUT
LTC1775
19