DC1898A - Schematic

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8
REVISION HISTORY
ECO
REV
_
2
INTVCC
JP5
CLKIN
1
535kHz
1
2
3
4
5
6
100K
FCM
PS/SYNC
BURST
PRODUCTION
APPROVED
DATE
DING L.
1-31-14
C62
1000pF
R48
MODE
E1
DESCRIPTION
INTVCC
2
PROGRAM
3
A
VIN2
R72
OPT
U1
VOUT1
5
1%
68.1K
VFB2
18
R43
649K
1%
C55
R70
0
OPT
VFB3
VFB1
VFB2
VFB3
SW1
0
C41
1%
0
1%
R79
OPT
1%
BOOST1
BG1
1500pF
ITH1
4
S1+
C42
C43
ITH2
C44
2.2nF
R35
0.1uF
19
Q2
BSZ123N08NS3G
DRVCC
VBIAS
BG1
R94
0
1
2
VBIAS
28
C11
4.7uF
D7
VIN2
SW2
BG2
0
SS1
37
SS2
21
SS3
TRK/SS1
SENSE2+
TG2
24
BOOST2
25
BG2
17
S2+
5
6
7
8
5
6
0.1uF
C52
TRK/SS2
E32
7
SENSE2-
16
EXTVCC
R26
RUN2 14
15
RUN3
RUN1
30
BOOST3
R96
0
RUN3
SW3
32
1
SW3
RUN3
ON
C
R99
OPT
6V
DRVSET
JP8
C60
OPT
2
OFF
2
3
VBIAS
1
3
SENSE3+
PGND
BG3
31
TG3
29
BG3
4
C64
1uF
COUT6
2.2uF
100V
1210
D5
4
COUT7
2.2uF
100V
1210
COUT8
2.2uF
100V
1210
COUT9
2.2uF
100V
1210
10V / 5.5A *
+ COUT10
33uF
63V
E25
GND
OPT
E27
VL3-
RSNS1
0.006
VIN+
VIN
L3 1.2uH
J7
VSW3
Q10
BSC042NE7NS3G
Q11
OPT
4
C63
C56
VOUT3
Q8
BSC042NE7NS3G
VIN
R82
OPT
CIN6
2.2uF
100V
1210
RSNS2
0.006
CIN7
2.2uF
100V
1210
CIN8
OPT.
100V
1210
CIN9
OPT
1210
CIN1
+ CIN2
33uF
63V
**
2.5V - 60V
J8
4
1
2
3
RUN3
INTVCC
1
10V
39
OPT
E26
TG3
S3+ 8
OPT
DRVSET
INTVCC 12
20
R41
E24
0.1uF
1
2
3
VPRG3
INTVCC
C48
SENSE3-
2
JP2
GND
Q9 OPT
DRVCC
2
C4
OPT
3
8.5V / 3A
E14
VOUT3
D8 OPT
BOOST3
RUN2
1
OPT
38
ON
OFF
C36
OPT
1206
2
R28
OPT
5
6
7
8
C38
1
2
3
3
R38
VBIAS
1
+ COUT5
68uF
10V
7343
27
5
6
7
8
RUN1 13
JP1
RUN2
COUT4
4.7uF
16V
1206
OPT
2
OFF
VOUT3
VOUT2
0.015
Q7-1
R40
0
S3- 9
E33
RUN2
R39
0
EXTVCC
RUN1
VBIAS
1
4
S2-
E13
RS2
VSW2
OPT
2
TRK/SS3
VOUT3
RUN1
ON
L2 6.5uH
Q7-2
1
2
3
SS3
Q4
BSZ123N08NS3G
1000pF
0.1uF
VOUT2
B
GND
1
2
3
OPT
VL2-
4
5
6
7
8
R74
C59
OPT.
C21
R95
0
23
C15
E23
C51
2.2uF
100V
4
22
3
BOOST2
10nF
R73
R5
0
Q3
BSZ123N08NS3G
OPT
7
8
TG2
ITH3
5V / 5A
OPT
GND
1
0.1uF
11
C32
DRVCC
C17
R75
3.6K
C54
+ COUT2
220uF
6.3V
1
2
3
ITH3
C47
OPT
COUT1
22uF
6.3V
VOUT3
26
ITH2
820pF
TRACK / SS2
B
VOUT1
0.009
E12
5
6
7
8
C53
R37
VSW1
Q5-1
0.1uF
0
E11
RS1
OPT
4
34 BOOST1
33
1
R34
Q5-2
2
15K
E10
VOUT1
L1 4.9uH
35
ITH1
68pF
100pF
C2
1
C58
OPT.
VL1-
4
TG1
2
R31
15K
TRACK / SS1
VIN1
C50
2.2uF
100V
D6 OPT
OPT
OPT
36
R78
R3
R2
3
C20
0.1uF
1%
E9
Q1
BSZ123N08NS3G
1000pF
VOUT3
VOUT2
R4
0
S1C14
TG1
10
4
FREQ
SENSE1+
OPT
VOUT2
2
1%
C49
R36
VFB1
SENSE1-
5
6
R33
68.1K
PLLIN/MODE
3
OPT
R32
6
R27
357K
1%
1
C37
R30
0
1
2
3
JP7 FSW
R29
0
LTC3899EFE
7
8
1%
5
6
7
8
0
1
2
3
R87
5
6
7
8
4
350kHz
5
6
7
8
A
C57
C
OPT
VIN-
OPT
1000pF
E30
JP4
R92
OPT
R80
0
R81
100
INTVCC
R97
0
R45
VSW1
VOUT2
S1+
OPT
R98
R47
TG1
VSW1
OPT
NOTE:
WHEN DCR SENSING IS IMPLEMENTED,
SHORT RSENSE1 & RSENSE2.
REMOVE R30, R29, R40, R39, R80 & R81
STUFF R61, R62 AND R91 WITH 0 OHMS.
CALCULATE R45, R47 & C14, R51, R53 & C15
AND R89, R90 & C56 PER THE DATA SHEET.
ALSO REFER TO QSG FOR EXAMPLE.
0
EXTVCC
R61
S1-
VL1-
E31
OPT
R51
VSW2
S2+
OPT
VSW3
OPT
R90
OPT
OPT
R62
OPT
S3+
E34
SGND
R91
VL2-
OPT
VBIAS
VIN
R85
OPT
R86
2.2
VOUT3
BG1
TG2
VSW2
S3-
R53
S2-
R93
EXTVCC
R89
VOUT1
R55
OPT
C61
SHT 2
OPTIONAL DCR SENSING
BG2
1uF
TG3
VSW3
OPT
VL3-
BG3
D
D
NOTE: UNLESS OTHERWISE SPECIFIED
CUSTOMER NOTICE
1. ALL RESISTORS ARE IN OHMS, 0603.
ALL CAPACITORS ARE IN MICROFARADS, 0603.
2. INSTALL SHUNTS AS SHOWN.
* OUTPUT 10V ONLY WHEN VIN < 10V, OTHERWISE VOUT3 FOLLOWS VIN.
DON'T CONNECT ANY LOAD.
** VIN NEEDS TO BE >4.5V TO START UP.
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
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1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
APPROVALS
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APP ENG.
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
TECHNOLOGY Fax: (408)434-0507
LTC Confidential-For Customer Use Only
HZ
TITLE: SCHEMATIC
DING L.
TRIPLE OUTPUT SYNCHRONOUS
STEP-UP/DUAL STEP-DOWN SUPPLY
SIZE
N/A
SCALE = NONE
DATE:
7
IC NO.
REV.
LTC3899EFE
DEMO CIRCUIT 1898A
Tuesday, November 04, 2014
2
SHEET 1
8
OF 2
VOUT3
VIN1
C70
0.22uF
1
2
3
Q19
OPT
VIN2
5
6
7
8
1
2
3
SHT 1
C67
1uF
4
TG2
C68
1uF
1
2
3
5
6
7
8
4
VSW2
Q18
OPT
5
6
7
8
5
6
7
8
4
VIN2
4
1
2
3
4
BG2
1
2
3
BG3
1
2
3
SHT 1
VSW3
Q15
OPT
C66
1uF
5
6
7
8
Q17
OPT
BG1
Q14
OPT
C65
1uF
VSW1
4
1
2
3
4
1
2
3
TG3
Q13
OPT
VIN1
4
TG1
5
6
7
8
Q12
OPT
5
6
7
8
Q16
OPT
5
6
7
8
C69
0.22uF
CUSTOMER NOTICE
APPROVALS
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES.
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APP ENG.
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
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
TECHNOLOGY
HZ
DING L.
TITLE: SCHEMATIC
TRIPLE OUTPUT SYNCHRONOUS
STEP-UP/DUAL STEP-DOWN SUPPLY
SIZE
N/A
SCALE = NONE
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900 www.linear.com
Fax: (408)434-0507
LTC Confidential-For Customer Use Only
IC NO.
LTC3899EFE
DEMO CIRCUIT 1898A
DATE: Tuesday, February 25, 2014
REV.
2
SHEET 2
OF 2