LTC3731
34
3731fc
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
FAX: (408) 434-0507
●
www.linear.com
LINEAR TECHNOLOGY CORPORATION 2005
LT 0711 REV C • PRINTED IN USA
1µF
V
CC
1000pF
S1
+
S1
–
S2
+
S2
–
S3
–
S3
+
V
CC
PLLIN
PLLFLTR
FCB
IN
+
IN
–
DIFFOUT
LTC3731G
EAIN
SGND
SENSE1
+
SENSE1
–
SENSE2
+
SENSE2
–
SENSE3
–
SENSE3
+
RUN/SS
I
TH
I
TH
UVADJ
CLK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
PGOOD
BOOST1
TG1
SW1
BOOST2
TG2
SW2
V
DR
BG1
PGND
BG2
BG3
SW3
TG3
BOOST3
PHASMD
SGND
100pF
SHORT
PLLFLTR TO
SGND
20k 147k
10Ω
V5
5V TO 7V
V
IN
M1
M2 D1
S1
+
S1
–
L1
0.003Ω
0.01µF
3.01k
10nF
100pF
1000pF
1µF
NC
3731 TA01
V
IN
: 9V TO 28V
V
OUT
: 5V AT 40A
SWITCHING FREQUENCY: 225kHz
PGOOD
47k
1Ω
1000pF
10µF
0.1µF
V5
0.1µF
0.1µF
V5
V5
V
IN
M3
M4 D2
S2
+
S2
–
L2
0.003Ω
V
IN
M5
M6 D3
S3
+
S3
–
L3
0.003Ω
47µF
10V
×3
C
OUT
V
IN
V
OUT
5V AT 40A
+
4.7µF
50V
×6
C
IN
47µF
35V
×4
+
C
IN
: KEMET T521X476M035ATE070 ×4
C
OUT
: SANYO 6TPE220MI ×3
D1 TO D3: DIODES INC. B340A
L1 TO L3: 2.2µH WURTH 7443320220
M1, M3, M5: RJK0305DPB
M2, M4, M6: RJK0330DPB
V
IN
18k
12k
RELATED PARTS
TYPICAL APPLICATION
PART NUMBER DESCRIPTION COMMENTS
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4.5V ≤ V
IN
≤ 38V, 0.8V ≤ V
OUT
≤ 5V
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with Diff Amp and DCR Temperature Compensation
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4.5V ≤ V
IN
≤ 38V, 0.8V ≤ V
OUT
≤ 5V
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4.5V ≤ V
IN
≤ 38V, 0.8V ≤ V
OUT
≤ 12V
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Diffamp and Three-State Output Drive
Operates with Power Blocks or DRMOS Devices,
3V ≤ V
IN
≤ 24V, t
ON(MIN)
= 20ns
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R
SENSE
or DCR Current Sensing and Tracking
Phase-Lockable Fixed 250kHz to 750kHz Frequency,
4V ≤ V
IN
≤ 24V, V
OUT3
Up to 13.5V
LTC3869/LTC3869-2 Dual Output, 2-Phase Synchronous Step-Down DC/DC Controller,
with Accurate Current Share
PLL Fixed 250kHz to 750kHz Frequency,
4V ≤ V
IN
≤ 38V, 0.6V ≤ V
OUT
≤ 12.5V
