LTC3728 Datasheet, PDF (32/32 Pages) Linear Technology – Dual, 550kHz, 2-Phase Synchronous Step-Down Switching Regulator

LTC3728
TYPICAL APPLICATIO
OPEN
0°
PHASMD TG1
180°
U1 ^TG2
LTC3729
90°
CLKOUT
90°
TG1
270°
U2 ^TG2
LTC3728
90°
PLLIN
I_IN
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
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC1530
High Power Step-Down Synchronous DC/DC Controller High Efficiency 5V to 3.3V Conversion at Up to 15A
in SO-8
LTC1628/LTC1628-PG/
LTC1628-SYNC
LTC1629/
LTC1629-PG
LTC1702
LTC1703
LTC1708-PG
LT1709/
LT1709-8
LTC1735
2-Phase, Dual Output Synchronous Step-Down
DC/DC Controller
20A to 200A PolyPhase^TM Synchronous Controllers
No R_SENSE 2-Phase Dual Synchronous Step-Down
Controller
No R_SENSE 2-Phase Dual Synchronous Step-Down
Controller with 5-Bit Mobile VID Control
2-Phase, Dual Synchronous Controller with Mobile VID
High Efficiency, 2-Phase Synchronous Step-Down
Switching Regulators with 5-Bit VID
High Efficiency Synchronous Step-Down
Switching Regulator
Reduces C_IN and C_OUT, Power Good Output Signal, Synchronizable,
3.5V ≤ V_IN ≤ 36V, I_OUT up to 20A, 0.8V ≤ V_OUT ≤ 5V
Expandable from 2-Phase to 12-Phase, Uses All
Surface Mount Components, No Heat Sink, V_IN up to 36V
550kHz, No Sense Resistor
Mobile Pentium^® III Processors, 550kHz,
V_IN ≤ 7V
3.5V ≤ V_IN ≤ 36V, VID Sets V_OUT1, PGOOD
1.3V ≤ V_OUT ≤ 3.5V, Current Mode Ensures
Accurate Current Sharing, 3.5V ≤ V_IN ≤ 36V
Output Fault Protection, 16-Pin SSOP
LTC1736
High Efficiency Synchronous Controller with 5-Bit Mobile Output Fault Protection, 24-Pin SSOP,
VID Control
3.5V ≤ V_IN ≤ 36V
LTC1778
No R_SENSE Current Mode 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
LTC1929/
2-Phase Synchronous Controllers
Up to 42A, Uses All Surface Mount Components,
LTC1929-PG
No Heat Sinks, 3.5V ≤ V_IN ≤ 36V
LTC3711
No R_SENSE Current Mode Synchronous Step-Down
Controller with Digital 5-Bit Interface
Up to 97% Efficiency, Ideal for Pentium III Processors,
0.925V ≤ V_OUT ≤ 2V, 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
No R_SENSE and PolyPhase are trademarks of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation.
3728fb
32 Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ^● FAX: [phone] ^● www.linear.com
LT 0406 REV B • PRINTED IN USA
© LINEAR TECHNOLOGY CORPORATION 2006