Datasheet

LTC3850/LTC3850-1
38
38501fc
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone]
l
FAX: [phone]
l
www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2007
LT 0311 REV C • PRINTED IN USA
TYPICAL APPLICATION
PART NUMBER DESCRIPTION COMMENTS
LTC1625/
LTC1775
No R
SENSE
™ Current Mode Synchronous Step-Down Controllers 97% Efficiency, No Sense Resistor, 16-Pin SSOP
LTC1735 High Efficiency Synchronous Step-Down Switching Regulator Programmable Fixed Frequency from 200kHz to 550kHz
LTC1778 No R
SENSE
Wide Input Range Synchronous Step-Down Controller Up to 97% Efficiency, 4V ≤ V
IN
≤ 36V, 0.8V ≤ V
OUT
≤ (0.9)(V
IN
),
I
OUT
Up to 20A
LTC3727A-1 Dual, 2-Phase Synchronous Controller Very Low Dropout; V
OUT
≤ 14V, 4V ≤ V
IN
≤ 36V
LTC3728 2-Phase 550kHz, Dual Synchronous Step-Down Controller QFN and SSOP Packages, High Frequency for Smaller L and C
LTC3729
20A to 200A PolyPhase
®
Synchronous Controllers
Expandable from 2-Phase to 12-Phase, Uses All Surface Mount
Components
LTC3731 3-Phase, Single Output From 250kHz to 600kHz Synchronous
Step-Down Controller
0.6V ≤ V
OUT
≤ 6V, 4.5V ≤ V
IN
≤ 32V, I
OUT
≤ 60A,
Integrated MOSFET Drivers
LTC3773 Triple Output DC/DC Synchronous Controller 3-Phase Step-Down DC/DC Controller,
3.3V ≤ V
IN
≤ 36V, Fixed Frequency 160kHz to 700kHz
LTC3810 100V Current Mode Synchronous Step-Down Switching Controller 0.8V ≤ V
OUT
≤ 0.93V
IN
, 6.2V ≤ V
IN
≤ 100V, No R
SENSE
LTC3826 Low I
Q
, Dual, 2-Phase Synchronous Step-Down Controller 30µA I
Q
, 0.8V ≤ V
OUT
≤ 10V, 4V ≤ V
IN
≤ 36V
LTC3828 Dual, 2-Phase Synchronous Step-Down Controller with Tracking Up to Six Phases, 0.8V ≤ V
OUT
≤ 7V, 4.5V ≤ V
IN
≤ 28V
LTC3834/
LTC3834-1
Low I
Q
, Synchronous Step-Down Controller 30µA I
Q
, 0.8V ≤ V
OUT
≤ 10V, 4V ≤ V
IN
≤ 36V
LT3845 Low I
Q
, High Voltage Single Output Synchronous Step-Down
DC/DC Controller
1.23V ≤ V
OUT
≤ 36V, 4V ≤ V
IN
≤ 60V, 120µA I
Q
PolyPhase is a registered trademark of Linear Technology Corporation. No R
SENSE
is a trademark of Linear Technology Corporation.
Figure 21. 1.1V/30A Dual Phase Core Converter, F
SW
= 400kHz
RELATED PARTS
0.1µF
TK/SS1
I
TH1
V
FB1
V
FB2
I
TH2
TK/SS2
SENSE2
–
BOOST1
BG1
V
IN
INTV
CC
BG2
PGND
BOOST2
SENSE1
+
RUN1
FREQ MODE
SW1 TG1SENSE1
–
PGOOD
RJK0301DPB
RJK0305DPB
20k
7.5k
2.55k
0.1µF
RJK0301DPB
RJK0305DPB
CMDSH-3
CMDSH-3
4.7µF
1µF
0.1µF
20k
L1
0.56µH
V
OUT
1.1V/30A
0.1µF
100k
220pF
1nF
LTC3850
38501 TA04
SENSE2
+
RUN2SGND
I
LIM
SW2 TG2
EXTV
CC
PGOOD
C
OUT1
330µF
2.5V
4x
L1, L2: VISHAY IHLP4040DZ-01 0.56µH
C
OUT
: SANYO 2R5TPE330M9
FOR SINGLE OUTPUT, DUAL PHASE OPERATION, TIE THE FOLLOWING PINS TOGETHER:
V
FB1
TO V
FB1
ITH1 TO ITH2
10µF
2x
V
IN
7V TO 14V
180µF
L2
0.56µH
RUN
2.21k
2.21k
10k
0.1µF
2.2nF
2.74k
20k
RUN
+
100µF
2x
+
2.2Ω
TK/SS1 TO TK/SS2
RUN1 TO RUN2