LTC3728_15 Datasheet, PDF (36/36 Pages) Linear Technology – Dual, 550kHz, 2-Phase Synchronous Step-Down Switching Regulator

LTC3728
TYPICAL APPLICATION
I_IN
OPEN
0°
PHASMD TG1
180°
U1 ^TG2
LTC3729
90° _CLKOUT
TG1 ^90°
270°
U2 ^TG2
LTC3728
90°
PLLIN
I₁
BUCK: 2.5V/15A
BUCK: 2.5V/15A
I₂
I₃
BUCK: 1.5V/15A
BUCK: 1.8V/15A
I₄
12V_IN
C_IN
I_IN*
2.5V_O/30A
I₁
I₂
1.5V_O/15A
1.8V_O/15A
3728 F14
I₃
I₄
*INPUT RIPPLE CURRENT CANCELLATION
INCREASES THE RIPPLE FREQUENCY AND
REDUCES THE RMS INPUT RIPPLE CURRENT
THUS, SAVING INPUT CAPACITORS
Figure 14. Multioutput PolyPhase Application
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PART NUMBER
DESCRIPTION
COMMENTS
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3.5V ≤ V_IN ≤ 36V
Output Fault Protection, 16-Pin SSOP
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I_OUT Up to 20A
LTC1929/LTC1929-PG 2-Phase Synchronous Controllers
Up to 42A, Uses All Surface Mount Components, No Heat Sinks,
3.5V ≤ V_IN ≤ 36V
LTC3711
No R_SENSE Current Mode Synchronous Step-Down Up to 97% Efficiency, Ideal for Pentium III Processors, 0.925V ≤ V_OUT ≤ 2V,
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4V ≤ V_IN ≤ 36V, I_OUT Up to 20A
LTC3729
20A to 200A, 550kHz PolyPhase Synchronous
Controller
Expandable from 2-Phase to 12-Phase, Uses All Surface Mount
Components, V_IN Up to 36V
PolyPhase is a registered trademark of Linear Technology Corporation. No R_SENSE is a trademark of Linear Technology Corporation.
3728fg
36 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
LT 0909 REV G • PRINTED IN USA
© LINEAR TECHNOLOGY CORPORATION 2006