5
dc1881af
DEMO MANUAL DC1881A
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SCHEMATIC DIAGRAM
5
5
4
4
3
3
2
2
1
1
D
D
C
C
B
B
A
A
16V
6.
3V
MO
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CCM
PU
L
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P
X
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L7070
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: U
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W
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IF
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1.
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2012
11
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TITLE:
A
PPR
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CB DE
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.
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.
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CHNO
L
O
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F
ax: (408)434-0507
M
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as
, C
A
9
50
35
Phone
: (
408)
432-
1900
1630 M
cCar
th
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.
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C
C
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ay 15,
2012
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1881A
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DAT
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R
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SH
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TITLE:
A
PPR
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A
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P
CB DE
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.
A
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.
T
E
CHNO
L
O
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F
ax: (408)434-0507
M
ilp
it
as
, C
A
9
50
35
Phone
: (
408)
432-
1900
1630 M
cCar
th
y Bl
vd
.
L
T
C
C
o
n
fid
en
ti
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CUSTOMER NOTI
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MADE
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M
ay 15,
2012
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HIG
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BO
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1881A
R
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O
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DESCRI
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DATE
APPROVED
ECO
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CHARL
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.
P
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2
4
-23-
12
__
R
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DESCRI
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APPROVED
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2
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DATE
APPROVED
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CHARL
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P
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ODUCT
ION
2
4
-23-
12
__
R11
0
R11
0
R17
0
R17
0
C4
0.
22uF
16V
C4
0.
22uF
16V
C26
10uF
50V
1210
C26
10uF
50V
1210
C10
2.
2uF
C10
2.
2uF
R27
0
R27
0
R29
(OP
T
)
R29
(OP
T
)
C22
0.
22uF
16V
C22
0.
22uF
16V
Q2
A
S
i4288DY
Q2
A
S
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4
3
5
6
TP
1
2
EX
T
V
C
C
TP
1
2
EX
T
V
C
C
C29C29
C17
22uF
16V
C17
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16V
CF
1
O
P
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CF
1
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CC2
0.
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CC2
0.
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Q1
B
S
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Q1
B
S
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2
1
7
8
R7
100K
R7
100K
R5
10
R5
10
R9
100
R9
100
R25
0
R25
0
R14
100
R14
100
R10
100
R10
100
R8
10
R8
10
C23
(OP
T
)
1210
C23
(OP
T
)
1210
C13
(OP
T
)
C13
(OP
T
)
JP1
ON
OFF
RUN
JP1
ON
OFF
RUN
1
3
2
RC
13K
RC
13K
R6
OP
T
R6
OP
T
R28
(OP
T
)
1206
R28
(OP
T
)
1206
R1
0
R1
0
C18
1
0uF
C18
1
0uF
U1
LT
C3789E
UF
D
U1
LT
C3789E
UF
D
VFB
26
SS
27
28
SENSE1-
1
ITH
2
SGND
3
MODE/PLLIN
4
FREQ
5
RUN
6
VINSNS
7
VOUTSNS
8
ILIM
9
10
IOSENSE-
11
TRIM
12
SW2
13
TG2
14
BOOST2
15
BG2
16
EXTVCC
17
INTVCC
18
VIN
19
PGND
21
BOOST1
22
SW1
24
PGOOD
25
TG1
23
BG1
20
SGND
29
TP
6
VI
N
6V
-
36V
TP
6
VI
N
6V
-
36V
CS
S
0.
1uF
CS
S
0.
1uF
R16
1
K
R16
1
K
D7
DF
LS
160
D7
DF
LS
160
D6
DF
LS
160
D6
DF
LS
160
JP2JP2
1
3
2
C7
0.
1uF
C7
0.
1uF
+
CO
UT
1
OP
T
16V
+
CO
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1
OP
T
16V
C35
(OP
T
)
1210
C35
(OP
T
)
1210
C11 68pF
C11 68pF
D5
DF
LS
160
D5
DF
LS
160
D8
B
Z
X
84C5V
1
D8
B
Z
X
84C5V
1
RF
B
2
8.
06K
RF
B
2
8.
06K
TP
3
VI
N
+
TP
3
VI
N
+
R2
0.
015
0.
25W
R2
0.
015
0.
25W
C19
22uF
16V
1210
C19
22uF
16V
1210
R18
0.
015
1W
R18
0.
015
1W
R24
10K
R24
10K
R12
O
P
T
R12
O
P
T
C16
22uF
16V
1210
C16
22uF
16V
1210
TP
5
SS
TP
5
SS
L1
5.
6uH
L1
5.
6uH
R23
0
R23
0
TP
7
GN
D
TP
7
GN
D
Q2
B
S
i4288DY
Q2
B
S
i4288DY
2
1
7
8
R21
121K
R21
121K
R26
10
R26
10
R30
41.
2
K
R30
41.
2
K
TP
1
3
VO
U
T
12V
/
2.
5A
MA
X
TP
1
3
VO
U
T
12V
/
2.
5A
MA
X
C12
(OP
T
)
1206
C12
(OP
T
)
1206
C14
(OP
T
)
1210
C14
(OP
T
)
1210
R3
100
R3
100
C9
10uF
C9
10uF
C8
0.
1uF
C8
0.
1uF
CC1
100pF
CC1
100pF
R22
OP
T
R22
OP
T
C15
1uF
50V
0805
C15
1uF
50V
0805
TP
4
P
GOOD
TP
4
P
GOOD
Q1
A
S
i4288DY
Q1
A
S
i4288DY
4
3
5
6
C25
50V
1210
C25
50V
1210
CF
22pF
CF
22pF
R20
0
R20
0
R13
100
R13
100
C20C20
RF
B
1
113K
RF
B
1
113K
C24
1uF
C24
1uF
TP
1
4
GN
D
TP
1
4
GN
D
R4
100
R4
100
R31
12.
1K
R31
12.
1K
TP
1
0
P
LLI
N
TP
1
0
P
LLI
N
D4
DF
LS
160
D4
DF
LS
160