1
®
FN9044.2
ISL6443
300kHz Dual, 180°
Out-of-Phase, Step-
Down PWM and Single Linear Controller
The ISL6443 is a high-performance, triple-output controller
optimized for converting wall adapter, battery or network
intermediate bus DC input supplies into the system supply
voltages required for a wide variety of applications. Each
output is adjustable down to 0.8V. The two PWMs are
synchronized 180° out of phase reducing the RMS input
current and ripple voltage.
The ISL6443 incorporates several protection features. An
adjustable overcurrent protection circuit monitors the output
current by sensing the voltage drop across the lower
MOSFET. Hiccup mode overcurrent operation protects the
DC/DC components from damage during output
overload/short circuit conditions. Each PWM has an
independent logic-level shutdown input (SD1
and SD2).
A single PGOOD signal is issued when soft-start is complete
on both PWM controllers and their outputs are within 10% of
the set point and the linear regulator output is greater than
75% of its setpoint. Thermal shutdown circuitry turns off the
device if the junction temperature exceeds +150°C.
Features
• Wide Input Supply Voltage Range
- Variable 5.6V to 24V
- Fixed 4.5V to 5.6V
• Three Independently Programmable Output Voltages
• Switching Frequency . . . . . . . . . . . . . . . . . . . . . . .300kHz
• Out of Phase PWM Controller Operation
- Reduces Required Input Capacitance and Power
Supply Induced Loads
• No External Current Sense Resistor
- Uses Lower MOSFET’s r
DS(ON)
• Bidirectional Frequency Synchronization for
Synchronizing Multiple ISL6443s
• Programmable Soft-Start
• Extensive circuit protection functions
- PGOOD
-UVLO
- Overcurrent
- Over-temperature
- Independent Shutdown for Both PWMs
• Excellent Dynamic Response
- Voltage Feed-Forward with Current Mode Control
• QFN Packages:
- QFN - Compliant to JEDEC PUB95 MO-220
QFN - Quad Flat No Leads - Package Outline
- Near Chip Scale Package footprint, which improves
PCB efficiency and has a thinner profile
• Pb-Free Plus Anneal Available (RoHS Compliant)
Applications
• Power Supplies with Multiple Outputs
• xDSL Modems/Routers
• DSP, ASIC, and FPGA Power Supplies
• Set-Top Boxes
• Dual Output Supplies for DSP, Memory, Logic, μP Core
and I/O
• Telecom Systems
Ordering Information
PART
NUMBER
PART
MARKING
TEMP.
RANGE (°C) PACKAGE
PKG.
DWG. #
ISL6443IR ISL6443IR -40 to 85 28 Ld 5x5 QFN L28.5x5
ISL6443IRZ
(See Note)
ISL6443IRZ -40 to 85 28 Ld 5x5 QFN
(Pb-free)
L28.5x5
Add “-T” or “-TK” suffix for tape and reel.
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100%
matte tin plate termination finish, which are RoHS compliant and
compatible with both SnPb and Pb-free soldering operations. Intersil
Pb-free products are MSL classified at Pb-free peak reflow
temperatures that meet or exceed the Pb-free requirements of
IPC/JEDEC J STD-020.
Data Sheet August 9, 2006
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
| Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright © Intersil Americas Inc. 2005-2006. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
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