DC1352A - Schematic

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2
3
4
5
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7
8
REVISION HISTORY
This circuit is proprietary to Linear Technology and supplied
for use with Linear Technology parts.
Customer Notice: Linear Technology has made a best effort to
design a circuit that meets customer-supplied specifications;
however, it remains the customer's responsibility to verify proper
and reliable operation in the actual application, Component
substitution and printed circuit board layout may significantly
affect circuit performance or reliability. Contact Linear
Applications Engineering for assistance.
ECO
REV
DESCRIPTION
3
DATE
PROTO
APPROVED
11/04/.08
INTVCC
OPTIONAL DCR SENSING:
R1
200K
A
NOTE: WHEN DCR SENSING IS IMPLEMENTED, SHORT R10 AND R17,
DO NOT STUFF R8,R9,R20 AND R21
A
E1
PGOOD1
TRACK1
JP5
E10
SS
TRACK
R2
3
TRACK1
VOUT2
C2 10pF
1
2
35.7K
R26
R3
11.5K
VOUT1
C1
0.1uF
OPT
R4
57.6K
1%
R5
R6
182K 1%
0
C3 22pF
MODE
R8
0
JP2
1
2
CCM
3
4
PULSE SKIP
5
6
BURST MODE
R11
8.2K
C4
U1
E4
SNS1-
VIN
VIN
R34
OPT
JP3
ON
1
2
ON
1
2
OFF
3
OFF
3
C
R36
OPT
C14
SW1
25
24
6
PLLIN/MODE
BG1
23
7
SGND
VIN
22
8
RUN1
PGND
21
RUN2
EXTVCC
SNS2+
11
12
R16 15K C15
13
C28
OPT
1%
R37
[1]
INTVCC
3300pF
14
C29
E2
SNS2-
INTVCC
SNS2+
BG2
VFB2
BOOST2
ITH2
SW2
TRACK/SS2
TG2
1
2
3
2.2
CMDSH-4E
C11
VIN
4.7uF
20
EXTVCC
*
10V
19
0.1uF
BG2 SHT 2
4
D3
17
R15
16
C16
2.2
0.1uF
Q3
BSZ097N04LS
E3
R19
976K
1%
4.7uF
50V
4.7uF
50V
R32
OPT
J4
GND
GND
C
R33
OPT
E13
Q4
BSZ097N04LS
VOUT2
L2 7.2uH
J5
VOUT2
CDEP105-7R2M
SW2 SHT 2
R20
0
VIN
4.5V - 36V
E6
0.008
OPT
R22
C7
SNS2+
1
2
3
R18
102K
1%
C17
OPT
CMDSH-4E
TG2 SHT 2
VIN
SNS2-
VIN
INTVCC
J3
R31
INTVCC
18
15
OPTIONAL DCR
SENSING
C13
+ 47uF
50V
C12
VIN
SNS1+
OPTIONAL DCR
SENSING
C27
EXTVCC
C20
10uF
16V
COUT2
+ 68uF
10V
COUT4
+ OPT
J6
R21
0
VOUT2
8.5V / 3A
GND
[2]
E14
GND
VOUT2
VOUT2
* EXTVCC
C21
C22
4.7uF
10V
OPT
R23
0
0
TRACK2
CONTRACT NO.
JP6
R24
TRACK
3
TRACK2
97.6K1%
ASSY
-A
U1
R35
R37
LTC3857EGN-1
OPT
OPT
SS
2
E15
[1]
GND
R17
1000pF
2.2uF
D
0
GND
E5
4
INTVCC
C19
J2
SNS1-
4
R14
C18
OPT
BG1
SHT 2
INTVCC
B
E12
OPT
D2
R13
VOUT1
3.3V / 5A
R30
BOOST1
47pF
+ COUT3
OPT
R29
OPT
Q2
BSZ097N04LS
0.1uF
FREQ
9
R28
OPT
26
SNS1-
SNS2- 10
R35
[1]
TG1
BSZ097N04LS
+ COUT1
220uF
4V
C10
27
5
JP4
RUN2
RUN1
PGOOD1
SNS1+
28
4
0
PLLIN / MODE
VFB1
100uF
6.3V
5
6
7
8
3
4
TRACK/SS1
C5
1
2
3
SNS1+
ITH1
Q1
1
2
3
2
R7
TG1 SHT 2
[1]
1
0.005
5
6
7
8
1000pF
5
6
7
8
4700pF
R38
OPT
J1
VOUT1
INTVCC
SGND
VOUT1
R10
C6
OPT
E9
L1 3.2uH
CDEP105-3R2M
C26
1%
100K
SW1 SHT 2
VIN
R27
B
E11
R9
0
5
6
7
8
INTVCC
APPROVALS
1
DRAWN MI
C23
R25
10K
1%
CHECKED
0.1uF
APPROVED
ENGINEER
DESIGNER
DATE
10/26/07
TECHNOLOGY
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
D
TITLE
SCH, LTC3857EGN-1 / LTC3858EGN-1, LOW QUIESCENT CURRENT
DUAL OUTPUT SYNCHRONOUS BUCK CONVERTER
SIZE
CAGE CODE
DWG NO
REV
3
DC1352A - A / B
-B
LTC3858EGN-1
1
66.5K
12.7K
2
* (14V MAX)
[2] FOR REGULATION VIN > 9V
3
Wednesday, July 22,2009
4
5
6
SCALE: NONE
FILENAME: 1352A-3.DSN
7
SHEET
1
8
OF
2
This circuit is proprietary to Linear Technology and supplied
for use with Linear Technology parts.
Customer Notice: Linear Technology has made a best effort to
design a circuit that meets customer-supplied specifications;
however, it remains the customer's responsibility to verify proper
and reliable operation in the actual application, Component
substitution and printed circuit board layout may significantly
affect circuit performance or reliability. Contact Linear
Applications Engineering for assistance.
REVISION HISTORY
ECO
VIN
REV
DESCRIPTION
3
C24
C25
OPT
OPT
DATE
PROTO
APPROVED
11/04/08
5
6
7
8
VIN
Q5
OPT
4
1
2
3
TG1
5
6
7
8
SW1
Q6
OPT
4
1
2
3
BG1
VIN
5
6
7
8
SHT 1
Q7
OPT
4
1
2
3
TG2
5
6
7
8
SW2
Q8
4
OPT
1
2
3
BG2
5
6
7
8
VIN
Q1X
4
OPT
1
2
3
TG1
5
6
7
8
SW1
X6
1
1
X5
X7
1
1
1
X1
1
X2
Represents
Tooling Holes
4
REPRESENTS STAND OFFS
1
2
3
BG1
Q2X
OPT
X4
on PCB
VIN
5
6
7
8
SHT 1
1
2
3
DRAWN MI
DATE
10/26/07
CHECKED
5
6
7
8
SW2
APPROVED
Q4X
OPT
4
1
2
3
BG2
CONTRACT NO.
APPROVALS
4
TG2
Q3X
OPT
TECHNOLOGY
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
TITLE
SCH, LTC3857EGN-1 / LTC3858EGN-1, LOW QUIESCENT CURRENT
DUAL OUTPUT SYNCHRONOUS BUCK CONVERTER
ENGINEER
DESIGNER
SIZE
CAGE CODE
DWG NO
REV
3
DC1352A - A / B
Wednesday, July 22, 2009
SCALE: NONE
FILENAME: 1352A-2.DSN
SHEET
2
OF
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