5
dc1787af
DEMO MANUAL DC1787A
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
ALL CAPACITORS ARE IN MICROFARADS, 0603.
NOTES: UNLESS OTHERWISE SPECIFIED
2. INSTALL SHUNTS AS SHOWN.
1. ALL RESISTORS ARE IN OHMS, 0603.
0.5A
VIN > 2.8V
1A
*
*
VIN > 4V
EN/UVLO
PGOOD
VIN
+VOUT
+VOUT
+VOUT
SIZE
DATE:
.
V
E
R
.
O
N
CI
SHEET
O
F
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax: (408)434-0507
Milpitas, CA 95035 Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
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
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
LT3759EMSE
1
1
M
P
25:
21
,1
10
2/
03/
90
SEPIC CONVERTER WITH WIDE INPUT VOLTAGE RANGE
KIM T.
ZHONGMING Y.
N/A
DEMO CIRCUIT 1787A
SIZE
DATE:
.
V
E
R
.
O
N
CI
SHEET
O
F
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax: (408)434-0507
Milpitas, CA 95035 Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
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
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
LT3759EMSE
1
1
M
P
25:
21
,1
10
2/
03/
90
SEPIC CONVERTER WITH WIDE INPUT VOLTAGE RANGE
KIM T.
ZHONGMING Y.
N/A
DEMO CIRCUIT 1787A
SIZE
DATE:
.
V
E
R
.
O
N
CI
SHEET
O
F
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY
Fax: (408)434-0507
Milpitas, CA 95035 Phone: (408)432-1900
1630 McCarthy Blvd.
LTC Confidential-For Customer Use Only
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
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
2
LT3759EMSE
1
1
M
P
25:
21
,1
10
2/
03/
90
SEPIC CONVERTER WITH WIDE INPUT VOLTAGE RANGE
KIM T.
ZHONGMING Y.
N/A
DEMO CIRCUIT 1787A
REVISION HISTORY
DESCRIPTION
DATE
APPROVED
ECO
REV
ZHONGMING Y.
PRODUCTION
1
09-30-11
_
REVISION HISTORY
DESCRIPTION
DATE
APPROVED
ECO
REV
ZHONGMING Y.
PRODUCTION
1
09-30-11
_
REVISION HISTORY
DESCRIPTION
DATE
APPROVED
ECO
REV
ZHONGMING Y.
PRODUCTION
1
09-30-11
_
E5
GND
E5
GND
E4
EN/UVLO
E4
EN/UVLO
Q1 RJK0652DPB
Q1 RJK0652DPB
2
4
5
3
1
D3
PDS360
D3
PDS360
2
1
3
CIN1 10uF 50V 1210
CIN1 10uF 50V 1210
E2
GND
E2
GND
R4 1.43k
R4 1.43k
COUT1 47uF 16V 1210
COUT1 47uF 16V 1210
JP1
RUN
SHDN
JP1
RUN
SHDN
1
3
2
COUT2 47uF 16V 1210
COUT2 47uF 16V 1210
C3
4.7uF 16V
0805
C3
4.7uF 16V
0805
R5 27.4k
R5 27.4k
C2 1uF 50V 0805
C2 1uF 50V 0805
U1
LT3759EMSE
U1
LT3759EMSE
INTVCC
9
SS
3
VC
1
FBX
2
GND
13
EN/UVLO
12
RT
4
SYNC
5
VIN
11
DRIVE
10
PGOOD
6
SENSE
7
GATE
8
R1 249k
R1 249k
CIN2 10uF 50V 1210
CIN2 10uF 50V 1210
C7 470pF
C7 470pF
R6 0
R6 0
C6 0.1uF
C6 0.1uF
L1B 15uH
L1B 15uH
2
4
E6
+VOUT
12V /
E6
+VOUT
12V /
JP2
ON
OFF
SYNC
JP2
ON
OFF
SYNC
1
3 2
E1
VIN
2.8V - 36V
E1
VIN
2.8V - 36V
L1A 15uH
DRQ127-150-R
L1A 15uH
DRQ127-150-R
1
3
+
CIN3 22uF 50V
SUN ELECT 50CE22BS
+
CIN3 22uF 50V
SUN ELECT 50CE22BS
E7
SYNC
E7
SYNC
RFBB 15.8k
RFBB 15.8k
E3
PGOOD
E3
PGOOD
C1 4.7uF 50V
1210
C1 4.7uF 50V
1210
RCS 0.005 2010
RCS 0.005 2010
R3 255k
R3 255k
RFBS 102k
RFBS 102k
C5 68nF
C5 68nF
R2 100k
R2 100k
D1
OPT
1N4148WT
D1
OPT
1N4148WT
1
2
