LTC3850-1_15 Datasheet, PDF (38/38 Pages) Linear Technology – Dual, 2-Phase Synchronous Step-Down Switching Controller

LTC3850/LTC3850-1
TYPICAL APPLICATION
2.55k
1nF
7.5k
0.1µF
220pF
2.2nF
2.74k
20k
20k
0.1µF
10k
RUN
SENSE1^– SENSE1⁺ RUN1 FREQ MODE SW1 TG1
TK/SS1
I_TH1
V_FB1
V_FB2
I_TH2
TK/SS2
SENSE2^–
LTC3850
BOOST1
BG1
V_IN
INTV_CC
BG2
PGND
BOOST2
SENSE2⁺ SGND RUN2 I_LIM EXTV_CC PGOOD SW2 TG2
0.1µF
PGOOD
20k
100k
0.1µF
CMDSH-3
2.2Ω
4.7µF
1µF
CMDSH-3
0.1µF
RJK0305DPB
2.21k
L1
0.56µH
RJK0301DPB
10µF ⁺
2x
V_IN
7V TO 14V
180µF
RJK0305DPB
RJK0301DPB
L2
0.56µH
2.21k
+
100µF
2x
V_OUT
1.1V/30A
C_OUT1
330µF
2.5V
4x
RUN
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
TK/SS1 TO TK/SS2
RUN1 TO RUN2
Figure 21. 1.1V/30A Dual Phase Core Converter, F_SW = 400kHz
38501 TA04
RELATED PARTS
PART NUMBER DESCRIPTION
COMMENTS
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I_OUT Up to 20A
Very Low Dropout; V_OUT ≤ 14V, 4V ≤ V_IN ≤ 36V
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Components
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0.6V ≤ V_OUT ≤ 6V, 4.5V ≤ V_IN ≤ 32V, I_OUT ≤ 60A,
Integrated MOSFET Drivers
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3-Phase Step-Down DC/DC Controller,
3.3V ≤ V_IN ≤ 36V, Fixed Frequency 160kHz to 700kHz
0.8V ≤ V_OUT ≤ 0.93V_IN, 6.2V ≤ V_IN ≤ 100V, No R_SENSE
30µA I_Q, 0.8V ≤ V_OUT ≤ 10V, 4V ≤ V_IN ≤ 36V
Up to Six Phases, 0.8V ≤ V_OUT ≤ 7V, 4.5V ≤ V_IN ≤ 28V
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.
38501fc
38 LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^l FAX: [phone] ^l www.linear.com
LT 0311 REV C • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 2007