LTC3731_15 Datasheet, PDF (34/34 Pages) Linear Technology – 3-Phase, 600kHz, Synchronous Buck Switching Regulator Controller

LTC3731
TYPICAL APPLICATION
1µF
V5
10Ω
SHORT
PLLFLTR TO
SGND
V_CC
1 _VCC
2 _PLLIN
CLK
PGOOD
3 _{PLLFLTR BOOST1}
4 _FCB
TG1
100pF
5 _IN+
SW1
20k
147k
6
LTC3731G
IN^–
BOOST2
7 _DIFFOUT
TG2
8 _EAIN
SW2
S1⁺
S1^{– 1000pF}
9 _SGND
10 _SENSE1+
11 _SENSE1–
V_DR
BG1
PGND
S2⁺
S2^{– 1000pF}
12 _SENSE2+
BG2
13 _SENSE2–
BG3
S3^–
0.01µF S3^{+ 1000pF}
14 _SENSE3–
SW3
15 _SENSE3+
TG3
100pF _10nF V_IN
3.01k
16
I_{TH 17}
18
RUN/SS
I_TH
UVADJ
BOOST3
PHASMD
SGND
18k
12k
36 _NC
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
PGOOD
47k
1Ω
0.1µF
M1
V5
5V TO 7V
V_IN
L1
0.003Ω
V5
0.1µF
1µF
10µF
M2
D1
S1⁺
S1^–
V_IN
M3
L2
0.003Ω
M4
D2
S2⁺
S2^–
0.1µF
V5
V_IN
M5
L3
0.003Ω
M6
D3
S3⁺
S3^–
V_IN: 9V TO 28V
V_OUT: 5V AT 40A
SWITCHING FREQUENCY: 225kHz
3731 TA01
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_OUT
5V AT 40A
47µF +
10V
×3
C_OUT
4.7µF +
50V
×6
V_IN
C_IN ^{9V TO 28V}
47µF
35V
×4
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC3829
LTC3856
LTC3855
LTC3860
LTC3853
LTC3869/LTC3869-2
3-Phase, Single Output Synchronous Step-Down Controller with
Diff Amp and DCR Temperature Compensation
2-Phase, Single Output Synchronous Step-Down DC/DC Controller
with Diff Amp and DCR Temperature Compensation
Dual, Multiphase, Synchronous Step-Down DC/DC Controller with
Diffamp and DCR Temperature Compensation
Dual, Multiphase, Synchronous Step-Down DC/DC Controller with
Diffamp and Three-State Output Drive
Triple Output, Multiphase Synchronous Step-Down DC/DC Controller,
R_SENSE or DCR Current Sensing and Tracking
Dual Output, 2-Phase Synchronous Step-Down DC/DC Controller,
with Accurate Current Share
Phase-Lockable Fixed 250kHz to 770kHz Frequency,
4.5V ≤ V_IN ≤ 38V, 0.8V ≤ V_OUT ≤ 5V
Phase-Lockable Fixed 250kHz to 770kHz Frequency,
4.5V ≤ V_IN ≤ 38V, 0.8V ≤ V_OUT ≤ 5V
Phase-Lockable Fixed Frequency 250kHz to 770kHz,
4.5V ≤ V_IN ≤ 38V, 0.8V ≤ V_OUT ≤ 12V
Operates with Power Blocks or DRMOS Devices,
3V ≤ V_IN ≤ 24V, t_ON(MIN) = 20ns
Phase-Lockable Fixed 250kHz to 750kHz Frequency,
4V ≤ V_IN ≤ 24V, V_OUT3 Up to 13.5V
PLL Fixed 250kHz to 750kHz Frequency,
4V ≤ V_IN ≤ 38V, 0.6V ≤ V_OUT ≤ 12.5V
34 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
3731fc
LT 0711 REV C • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 2005